Me and partner weigh in around 420lbs together. When we are both on the bike the back drops very low, not sure if this is normal for two-up riding? I have adjust the suspension, but i have no idea what setting it is on due to rust and wear.
However i clicked it a few turns to adjust the pre-load and it feels alot stiffer, but it bottomed out on a speed bump (was going 20mph).. just wanted to know if this is normal. With this weight should i adjust the pre-load to the max setting of 7?
Thanks
Yes, it should be adjusted to 7. And that is turning it clockwise as you look down on it.
The rear tire should also have increased air pressure in it. Manual suggests 41psi
In case you don't know, the gross load (weight of bike, accessories, payload, ride & pillion) for the bike must not exceed 840 lbs - 381kg.
The bike itself weighs 400lbs dry, Add your 420lbs plus the weight of gas (6lbs a gallon) 30lbs and your total weight is 850lbs - you have exceeded the Gross Vehicle Weight of the bike. recommended not to ride it like this as handling and control may be severely effected.
Michael
Quote from: mister on September 24, 2011, 01:55:53 PM
Yes, it should be adjusted to 7. And that is turning it clockwise as you look down on it.
The rear tire should also have increased air pressure in it. Manual suggests 41psi
In case you don't know, the gross load (weight of bike, accessories, payload, ride & pillion) for the bike must not exceed 840 lbs - 381kg.
The bike itself weighs 400lbs dry, Add your 420lbs plus the weight of gas (6lbs a gallon) 30lbs and your total weight is 850lbs - you have exceeded the Gross Vehicle Weight of the bike. recommended not to ride it like this as handling and control may be severely effected.
Michael
My manual says "curb weight" (all fluids and full gas) for 09 is 436lbs ...this allows only 204 lbs for driver, passenger, accessories and cargo........
Cookie
me and my fiance weigh about 500 together (im a big boy) i threw a katana shock on under it, and a 15t for some power and it runs great... upgrade your brakes, and make sure you use your rear break a bit harder than normal (you have more grip on the back with the extra weight...
Quote from: twocool on September 24, 2011, 04:09:13 PM
Quote from: mister on September 24, 2011, 01:55:53 PM
Yes, it should be adjusted to 7. And that is turning it clockwise as you look down on it.
The rear tire should also have increased air pressure in it. Manual suggests 41psi
In case you don't know, the gross load (weight of bike, accessories, payload, ride & pillion) for the bike must not exceed 840 lbs - 381kg.
The bike itself weighs 400lbs dry, Add your 420lbs plus the weight of gas (6lbs a gallon) 30lbs and your total weight is 850lbs - you have exceeded the Gross Vehicle Weight of the bike. recommended not to ride it like this as handling and control may be severely effected.
Michael
My manual says "curb weight" (all fluids and full gas) for 09 is 436lbs ...this allows only 204 lbs for driver, passenger, accessories and cargo........
Cookie
Japanese/European sportbikes aren't made for "bigger" people. Just like Japanese/European sports cars aren't.
That being said, on a STOCK bike you're way over recommended weight as one of the other posters said. Not only do you lose ponies because your power/weight ratio is suffering, you could seriously damage the frame bottoming out your bike at higher speeds. Fix it by getting a better suspension system. Particularly one from a heavier bike.
Also, make sure you're filling up your rear tire to 41 psi to accommodate the passenger.
Quote from: crzydood17 on September 24, 2011, 04:40:32 PM
me and my fiance weigh about 500 together (im a big boy) i threw a katana shock on under it, and a 15t for some power and it runs great... upgrade your brakes, and make sure you use your rear break a bit harder than normal (you have more grip on the back with the extra weight...
If by "power" you mean "horsepower", 15T doesn't give you power, it gives you acceleration at the sacrifice of top speed. No ponies are gained upgrading the gearing.
Curb weight of GS is approx 420# for a naked GS500/E and 440# for a GS500F with fairings. Gross vehicle weight is approx 840# so you have 400-420# left for passengers and load. Like suggested above, crank up the rear spring rating to max and tire pressure to max shown on sidewall, around 40 psi in most cases. The load rating of the tires on a vehicle is a significant part of determing the load rating of the vehicle. Suggest you replace stock 130/70 (584# rated) with a 140/80 (716# rated) tire next time you get a new rear tire. Besides increasing the load rating it will also raise the rear of your heavily loaded GS back up about 3/4" keeping the handling closer to normal.
Wow heaps of advice cheers guys.
Will get the tire pressure's sorted i have a page from this forum suggestion the PSI's for a pillion etc.
After searching about i concluded a Katana shock would be best for me and my pillion. Which year shock will i need for a '93 GS500E ??
Thanks again everyone
Don't sweat it, in Viet Nam I saw entire families ( sometimes 5 or 6 people ) including luggage, the dog, and maybe a small pig traveling long distances on bad roads on Honda 50 step throughs.-----Old poorly maintained Honda 50s at that, and I'm talking all the above on one bike, It must be seen to be believed.
Ok, they were small people----but still.
Quote from: CraiGDaniel on September 24, 2011, 09:39:33 AM
Me and partner weigh in around 420lbs together. When we are both on the bike the back drops very low, not sure if this is normal for two-up riding? I have adjust the suspension, but i have no idea what setting it is on due to rust and wear.
However i clicked it a few turns to adjust the pre-load and it feels alot stiffer, but it bottomed out on a speed bump (was going 20mph).. just wanted to know if this is normal. With this weight should i adjust the pre-load to the max setting of 7?
Thanks
I would certainly suggest upgrading the rear shock and doing some work the forks as well. I weigh 250 myself (I know, big guy for a GS500) and riding alone I have the stock shock at its highest setting and have installed 1" fork spacers to avoid bottoming out. I have to ask, how does the bike perform with the two of you on it? Just with me its pretty sluggish as is off the line, haven't tried any 2-up.
Hi Captain Slow. I havn't noticed much difference, only off the line. The bike will still do 100mph just about, with us both on it and i was able to overtake fairly easily at 70.
Definately slower on the acceleration, but not enough for it to be something to worry about.
If by "power" you mean "horsepower", 15T doesn't give you power, it gives you acceleration at the sacrifice of top speed. No ponies are gained upgrading the gearing.
Actually acceleration is only improved in one gear....1st........and only at the beginning of first (from a dead stop)....
Cookie
Quote
If by "power" you mean "horsepower", 15T doesn't give you power, it gives you acceleration at the sacrifice of top speed. No ponies are gained upgrading the gearing.
If you actually wanna be a duck about it, a 15T gives you more leverage in all gears, Torque is a metric of leverage, If I dyno a GS500 in first gear vs a GS500 with a 15T in first gear... the one with the 15T will show higher numbers. Power is a synonym with torque, If I increased my applicable torque I increased my power. Oh and a side note, I gain top end by having a 15T not lose it as the 16T hits a power/wind resistance barrier and the added torque of the 15T allows a slightly better spot in the power band allowing for higher top speed! AND FURTHERMORE! Since the 15T sprocket is slightly smaller and lighter than a 16T I decreased my rotational mass and INCREASED MY HORSEPOWER no matter how slight it still is a increase. Next time before you speak, remember I am watching and waiting in the background just to call you out on how stupid you really are.
(http://img153.imageshack.us/img153/8674/themoreyouknow2b.jpg)
Quote from: crzydood17 on September 25, 2011, 06:33:12 AM
Quote
If by "power" you mean "horsepower", 15T doesn't give you power, it gives you acceleration at the sacrifice of top speed. No ponies are gained upgrading the gearing.
If you actually wanna be a duck about it, a 15T gives you more leverage in all gears, Torque is a metric of leverage, If I dyno a GS500 in first gear vs a GS500 with a 15T in first gear... the one with the 15T will show higher numbers. Power is a synonym with torque, If I increased my applicable torque I increased my power. Oh and a side note, I gain top end by having a 15T not lose it as the 16T hits a power/wind resistance barrier and the added torque of the 15T allows a slightly better spot in the power band allowing for higher top speed! AND FURTHERMORE! Since the 15T sprocket is slightly smaller and lighter than a 16T I decreased my rotational mass and INCREASED MY HORSEPOWER no matter how slight it still is a increase. Next time before you speak, remember I am watching and waiting in the background just to call you out on how stupid you really are.
(http://img153.imageshack.us/img153/8674/themoreyouknow2b.jpg)
Ok....We are headed for the Tard Farm now....
Your understanding of this physics is partially correct and mostly hazy.....
Let's start somewhere... like this statement, "Power is a synonym with torque"
Not so! Power is torque times RPM
If you come to grips with that basic premise of physics...I think you find that the rest of what you state above is also kind of "off"...
Or we can simply go around calling each other "stupid" if you wish...
Cookie
http://www.allpar.com/eek/hp-vs-torque.html
Help in understanding power ..torque... rpm... acceleration... shift points
Cookie
Cookie, you shouldn't argue with someone who is Crzy----and particularly if they can't spell it.
And cookie, stop referencing posts to "we're heading to the tard farm now". It's as if you secretly Want posts to end up there, unseen, for some reason. :dunno_black:
As for HP vs Torque... saw a chart the other day (which I cannot seem to find at the moment but will repost it when I do) comparing dfferent bikes over torque, hp, etc. The ducati had the most torque by a mile but nowhere near the most HP.
Michael
WHOA where did I ever say "horsepower" = torque. Horsepower is a equation of torque, specifically Torque*RPM/5250=Horsepower
Power is merely a general term that describes force, torque is rotational force. I never said in any way in that first post that a 15T increased my "Horsepower" I stated it increased my power. If anyone has ridden a GS500 with 15T vs 16T they understand it has more power.
Past that, none of what I stated was "off" in any way. You can call me wrong all day long and twist words, if you think I was wrong prove it!
Yes, torque is a rotational force, but if you go one step backwards before it becomes rotational, torque can be seen as....pressure applied to the top of the piston regardless of weather the piston moves or not.
(during my vocational training it was presented to me this way)
Carry on :thumb:
actually that is wrong, the entire point of a engine is to turn longitudinal force (expanding super heated nitrogen) into rotational torque (spinning tires). Don't listen to your vocational school. I went to Wyotech, the collective knowledge of the students outweighed the knowledge of the teachers. The books are great though! I kept all of mine and use them as great reference tools.
Quote from: mister on September 25, 2011, 11:41:08 AM
And cookie, stop referencing posts to "we're heading to the tard farm now". It's as if you secretly Want posts to end up there, unseen, for some reason. :dunno_black:
As for HP vs Torque... saw a chart the other day (which I cannot seem to find at the moment but will repost it when I do) comparing dfferent bikes over torque, hp, etc. The ducati had the most torque by a mile but nowhere near the most HP.
Michael
When members post such statements as this:
"Next time before you speak, remember I am watching and waiting in the background just to call you out on how stupid you really are."
It belongs in the tard farm....
If we want to discuss a topic rationally...then let's keep it "nicer".
Torque, Horsepower, and RPM are physics terms with specific definitions.....and certain relationships..
Cookie
Quote from: crzydood17 on September 25, 2011, 12:47:35 PM
WHOA where did I ever say "horsepower" = torque. Horsepower is a equation of torque, specifically Torque*RPM/5250=Horsepower
Power is merely a general term that describes force, torque is rotational force. I never said in any way in that first post that a 15T increased my "Horsepower" I stated it increased my power. If anyone has ridden a GS500 with 15T vs 16T they understand it has more power.
Past that, none of what I stated was "off" in any way. You can call me wrong all day long and twist words, if you think I was wrong prove it!
If power does not mean horsepower...then please define power......
Cookie
Quote from: crzydood17 on September 25, 2011, 02:01:53 PM
actually that is wrong, the entire point of a engine is to turn longitudinal force (expanding super heated nitrogen) into rotational torque (spinning tires). Don't listen to your vocational school. I went to Wyotech, the collective knowledge of the students outweighed the knowledge of the teachers. The books are great though! I kept all of mine and use them as great reference tools.
Motor easy Einstein...the guy worked for Cummings Engines and was just presenting the whole torque issue in a more fundamental form.
Quote from: twocool on September 25, 2011, 02:09:49 PM
Quote from: crzydood17 on September 25, 2011, 12:47:35 PM
WHOA where did I ever say "horsepower" = torque. Horsepower is a equation of torque, specifically Torque*RPM/5250=Horsepower
Power is merely a general term that describes force, torque is rotational force. I never said in any way in that first post that a 15T increased my "Horsepower" I stated it increased my power. If anyone has ridden a GS500 with 15T vs 16T they understand it has more power.
Past that, none of what I stated was "off" in any way. You can call me wrong all day long and twist words, if you think I was wrong prove it!
If power does not mean horsepower...then please define power......
Cookie
power is force, it can be mechanical with the subcategories of rotational and longitudinal, electrical, and emotional.
We are dealing with mechanical in the subsection of rotational, thus torque.
Remember horsepower is only a function of torque, it is torque over time or RPM if you like. Horsepower is neither a technical term nor a universally accepted premise. Being merely an equation makes it hard to justify even using horsepower in a technical sense. I can make up a new equation and start rating cars in Crazypower. Torque is the only thing that a dynomometer can measure and then it uses the equation to make the horsepower figures.
hmm .. Once again .. Its happened .. Note to self .. Avoid listening to religious discussions, political arguments.... And now (variously qualified levels i guess?) engineering devoted persons trying to prove that they are the 'most righttest! So nyah nyah!'
so long as the bike starts and runs smooth and you get a good ride on the day .. Who cares where the energy comes from? If it came from blue and orange cats but still made the bike run then that is enough for me :)
oh i nearly forgot .. The topic :)
CraigDaniel .. May you have nice touring rides with you lovely girl on the back .. Hopefully these nutcases can put their hackles down long Enough to suggest some good SUSPENSION solutions .. But there a lot of other thread info on which katana shocks fit which bike .. Quicker to search it i reckon
Quote from: Janx101 on September 25, 2011, 03:05:53 PM
hmm .. Once again .. Its happened .. Note to self .. Avoid listening to religious discussions, political arguments.... And now (variously qualified levels i guess?) engineering devoted persons trying to prove that they are the 'most righttest! So nyah nyah!'
so long as the bike starts and runs smooth and you get a good ride on the day .. Who cares where the energy comes from? If it came from blue and orange cats but still made the bike run then that is enough for me :)
oh i nearly forgot .. The topic :)
CraigDaniel .. May you have nice touring rides with you lovely girl on the back .. Hopefully these nutcases can put their hackles down long Enough to suggest some good SUSPENSION solutions .. But there a lot of other thread info on which katana shocks fit which bike .. Quicker to search it i reckon
Yeah guess my thread got hijacked and trolled, oh well. Same old standard shet for most forums. You're right we just want a stable, comfy ride. I have spent an hour searching but there doesn't seem to be specific info for my bikes year, either way i will keep looking. Or maybe someone will come back on topic and throw me a bone?
Lol, cheers for reply mate.
Absolutely----you ask a simple question and a bunch of eggheads morph it into a technical manual, and the next thing you know they are rolling around in the dirt in a double head lock.
Quote from: CraiGDaniel on September 25, 2011, 04:22:01 PM
Quote from: Janx101 on September 25, 2011, 03:05:53 PM
hmm .. Once again .. Its happened .. Note to self .. Avoid listening to religious discussions, political arguments.... And now (variously qualified levels i guess?) engineering devoted persons trying to prove that they are the 'most righttest! So nyah nyah!'
so long as the bike starts and runs smooth and you get a good ride on the day .. Who cares where the energy comes from? If it came from blue and orange cats but still made the bike run then that is enough for me :)
oh i nearly forgot .. The topic :)
CraigDaniel .. May you have nice touring rides with you lovely girl on the back .. Hopefully these nutcases can put their hackles down long Enough to suggest some good SUSPENSION solutions .. But there a lot of other thread info on which katana shocks fit which bike .. Quicker to search it i reckon
Yeah guess my thread got hijacked and trolled, oh well. Same old standard shet for most forums. You're right we just want a stable, comfy ride. I have spent an hour searching but there doesn't seem to be specific info for my bikes year, either way i will keep looking. Or maybe someone will come back on topic and throw me a bone?
Lol, cheers for reply mate.
We already did. This topic was "over" a page ago. The SV650 shock and Katana shock are both great options, and you can read more about them on the wiki.
The remaining arguments stemmed from me correcting someone on something that was so absurdly wrong that I couldn't contain myself. Anyone who tells you a 15T gave them ponies is wrong. That being said, I never accused anyone of saying it did. I was just making sure he wasn't going off the deep end and saying the 15T gave him more ponies. Which it doesn't. No matter which way you spin it and no matter what dyno you take a rip on.
Apparently he was referencing "power" in terms of the numbers his ass-dyno gave him.
power is force, it can be mechanical with the subcategories of rotational and longitudinal, electrical, and emotional.
We are dealing with mechanical in the subsection of rotational, thus torque.
Remember horsepower is only a function of torque, it is torque over time or RPM if you like. Horsepower is neither a technical term nor a universally accepted premise. Being merely an equation makes it hard to justify even using horsepower in a technical sense. I can make up a new equation and start rating cars in Crazypower. Torque is the only thing that a dynomometer can measure and then it uses the equation to make the horsepower figures.
[/quote]
I disagree and here is why....power is not force.....force is force and power is power ...two different things....
Power is in units of work and time.....(force, distance and time to be exact) whether it is horsepower, or watts or any other units of measure. Force does not contain time....
Horsepower is a technical term....it is widely used and precisely defined.....
You are correct that power can be a factor or torque and time (or rpm). But you are incorrect that power is force alone.
You made a premise that lowering the gear ratio somehow increases "power" and this is not true.
Let me give you an example...
Cruising along at 50 MPH....my tach will read 4000 RPM in 6th gear....
I shift to lower gear(5th) and the Tach will read 4500 rpm.....and maintain 50 MPH
What is the change in power????
Cookie
Quote from: CraiGDaniel on September 25, 2011, 04:22:01 PM
Quote from: Janx101 on September 25, 2011, 03:05:53 PM
hmm .. Once again .. Its happened .. Note to self .. Avoid listening to religious discussions, political arguments.... And now (variously qualified levels i guess?) engineering devoted persons trying to prove that they are the 'most righttest! So nyah nyah!'
so long as the bike starts and runs smooth and you get a good ride on the day .. Who cares where the energy comes from? If it came from blue and orange cats but still made the bike run then that is enough for me :)
oh i nearly forgot .. The topic :)
CraigDaniel .. May you have nice touring rides with you lovely girl on the back .. Hopefully these nutcases can put their hackles down long Enough to suggest some good SUSPENSION solutions .. But there a lot of other thread info on which katana shocks fit which bike .. Quicker to search it i reckon
Yeah guess my thread got hijacked and trolled, oh well. Same old standard shet for most forums. You're right we just want a stable, comfy ride. I have spent an hour searching but there doesn't seem to be specific info for my bikes year, either way i will keep looking. Or maybe someone will come back on topic and throw me a bone?
Lol, cheers for reply mate.
Sorry for the side track....What year GS do you have?.....I can get you exact numbers form service manual....
But I'm pretty sure your weight is going to be "over" which leaves you little to improve the situation...
You didn't mention any problems starting off in first gear...so a new sprocket with less teeth wouldn't help the ride..........
Seems that the advice already given is what you need to do...set the shock to 7 or get bigger shock....
Cookie
bolt the motor to an engine based dyno instead of a road dyno, that measures how much power the engine will have.
in cars at least, the diff ratio makes NO DIFFERENCE to the power produced by the motor, it just makes a difference to how you use that power
http://en.wikipedia.org/wiki/Power_(physics)#Mechanical_power
http://en.wikipedia.org/wiki/Torque
http://en.wikipedia.org/wiki/Horsepower
read up...
GTscott, your perfectly correct!
Quote from: crzydood17 on September 25, 2011, 05:38:47 PM
http://en.wikipedia.org/wiki/Power_(physics)#Mechanical_power
http://en.wikipedia.org/wiki/Torque
http://en.wikipedia.org/wiki/Horsepower
read up...
GTscott, your perfectly correct!
Congrats on accidentally shooting yourself in the foot. In the horsepower article HP is abbreviated "power". Power is physics is the amount of work performed over time, and "work" when speaking a motorcycle or car is horsepower. I have no idea why you linked torque. Horsepower and torque are directly related, hence the term 'torque curve' when describing how much "work" a vehicle can do during the sample time. As RPMs rise torque has a tendency to rise, and subsequently HP follows. At the peak of a torque curve is where maximum horsepower is gained, meaning that at X RPM the vehicle will be most efficiently "doing work". Horsepower is essentially an esoteric unit that makes telling someone how "powerful" a car is within it's range fairly easy. You have to consider power/weight ratio too. But you said power, that's why I brought it up. The wikipedia article agrees with me. POWER is HORSEPOWER when talking about vehicles and engines. You could link wikipedia articles until the topic is locked but you won't be able to find evidence of otherwise.
The point of the story is by changing the gearing of a motorcycle you aren't improving anything but how quickly you will reach the optimum point in your torque curve. If you're putting 800 lbs on a performance modified GS500 that has, for argument's sake, 55 HP you're cutting the amount of work the engine could do under load by at least half.
The second point is, why not get a bigger displacement bike if that's the case. I'd imagine with that much weight on the bike 100cc scooters will be moving quicker than you.
Quote from: Dr.McNinja on September 25, 2011, 09:15:03 PM
Quote from: crzydood17 on September 25, 2011, 05:38:47 PM
http://en.wikipedia.org/wiki/Power_(physics)#Mechanical_power
http://en.wikipedia.org/wiki/Torque
http://en.wikipedia.org/wiki/Horsepower
read up...
GTscott, your perfectly correct!
Congrats on accidentally shooting yourself in the foot. In the horsepower article HP is abbreviated "power". Power is physics is the amount of work performed over time, and "work" when speaking a motorcycle or car is horsepower. I have no idea why you linked torque. Horsepower and torque are directly related, hence the term 'torque curve' when describing how much "work" a vehicle can do during the sample time. As RPMs rise torque has a tendency to rise, and subsequently HP follows. At the peak of a torque curve is where maximum horsepower is gained, meaning that at X RPM the vehicle will be most efficiently "doing work". Horsepower is essentially an esoteric unit that makes telling someone how "powerful" a car is within it's range fairly easy. You have to consider power/weight ratio too. But you said power, that's why I brought it up. The wikipedia article agrees with me. POWER is HORSEPOWER when talking about vehicles and engines. You could link wikipedia articles until the topic is locked but you won't be able to find evidence of otherwise.
The point of the story is by changing the gearing of a motorcycle you aren't improving anything but how quickly you will reach the optimum point in your torque curve. If you're putting 800 lbs on a performance modified GS500 that has, for argument's sake, 55 HP you're cutting the amount of work the engine could do under load by at least half.
The second point is, why not get a bigger displacement bike if that's the case. I'd imagine with that much weight on the bike 100cc scooters will be moving quicker than you.
Thank you Doctor!
Cookie
Quote from: Dr.McNinja on September 25, 2011, 09:15:03 PM
Quote from: crzydood17 on September 25, 2011, 05:38:47 PM
http://en.wikipedia.org/wiki/Power_(physics)#Mechanical_power
http://en.wikipedia.org/wiki/Torque
http://en.wikipedia.org/wiki/Horsepower
read up...
GTscott, your perfectly correct!
Congrats on accidentally shooting yourself in the foot. In the horsepower article HP is abbreviated "power". Power is physics is the amount of work performed over time, and "work" when speaking a motorcycle or car is horsepower. I have no idea why you linked torque. Horsepower and torque are directly related, hence the term 'torque curve' when describing how much "work" a vehicle can do during the sample time. As RPMs rise torque has a tendency to rise, and subsequently HP follows. At the peak of a torque curve is where maximum horsepower is gained, meaning that at X RPM the vehicle will be most efficiently "doing work". Horsepower is essentially an esoteric unit that makes telling someone how "powerful" a car is within it's range fairly easy. You have to consider power/weight ratio too. But you said power, that's why I brought it up. The wikipedia article agrees with me. POWER is HORSEPOWER when talking about vehicles and engines. You could link wikipedia articles until the topic is locked but you won't be able to find evidence of otherwise.
The point of the story is by changing the gearing of a motorcycle you aren't improving anything but how quickly you will reach the optimum point in your torque curve. If you're putting 800 lbs on a performance modified GS500 that has, for argument's sake, 55 HP you're cutting the amount of work the engine could do under load by at least half.
The second point is, why not get a bigger displacement bike if that's the case. I'd imagine with that much weight on the bike 100cc scooters will be moving quicker than you.
Let me bring this down for you
(http://upload.wikimedia.org/wikipedia/commons/thumb/f/f2/Palanca-ejemplo.jpg/800px-Palanca-ejemplo.jpg)
This is a lever, A lever is a simple machine that is not the same length on both sides of a fulcrum that allows a user to exert a small amount of force over a longer distance and multiply that force on the other end at the cost of distance moved.
(http://upload.wikimedia.org/wikipedia/commons/2/28/Roller_chain_drive_%28Army_Service_Corps_Training%2C_Mechanical_Transport%2C_1911%29.jpg)
This is a chain and sprocket, it has the same principal of a lever, the smaller circumference gear spins the larger one, depending on the ratio (teeth) the small gear makes X number of turns to get 1 turn of the larger one.
now lets get back from the basics, a stock GS500 has a 16/39 ratio that means that the gearing has a 2.4375 to 1 ratio, If horsepower/power is a equation of torque as stated above then any increase of torque is a increase in horsepower at the given ratio.
Remember we are not discussing horsepower at the crank, this is why I do not call it horsepower it is merely power.
So back to ratios
16/39 = 2.4375/1
15/39 = 2.6/1
anyone who has ever used a breaker bar or torque wrench knows that the larger your lever the more torque you can apply to the nut/bolt, the same goes with gears. The larger your X/1 ratio the more torque you apply to the wheel.
these are the ratios for the GS500 transmission
1st - 16.29:1
2nd - 11.76:1
3rd - 9.14:1
4th - 7.44:1
5th - 6.36:1
6th - 5.64:1
notice the very very large multiplication in all gears, now lets use this to calculate peak torque in each gear. the GS500 produces roughly 30ft/lbs of torque at 7500 RPM. Now its time to see the power of ratios
1st - 16.29:1 16T= 1191 Ft/lbs 15t=1270 ft/lbs
2nd - 11.76:1 16T= 859 Ft/lbs 15t= 917 ft/lbs
3rd - 9.14:1 16T= 668 Ft/lbs 15t=712 ft/lbs
4th - 7.44:1 16T= 544 Ft/lbs 15t=580 ft/lbs
5th - 6.36:1 16T= 465 Ft/lbs 15t=496 ft/lbs
6th - 5.64:1 16T= 412 Ft/lbs 15t=439 ft/lbs
Those are the peak torques of the gears at 7500 RPM the peak torque of the engine, quite impressive how low geared this bike is. There is a reason why we dyno cars in 4-5th gear because its the closest ratio to 1/1, if I dynoed a Honda in first gear it would throw down 1000+ftlbs of torque and 1500+horse power.
So in conclusion, you can argue it till the day you die, if you can't bring numbers please don't question mine. A 15T sprocket on our bikes makes more power at the wheel! There is no change in the power at the crank, but massive changes at the tire.
Also if I wanted a bigger bike I would buy one, I like my bike, quick as I need and 50mpg.
Nice numbers....
so all I gotta do is run with 16 th and always stay one gear lower than you with 15
...then I always have more torque to the rear wheel than you...(except in 1st....)
Changing sprockets only really matters in 1st and 6th.....all you do is "shift" the chart.....
So, In fact with my 16 th....my bike will be FASTER in any given gear at a given rpm (say 7500 for instance where you are in the "power band" (except possibly 6th due to high wind drag)
But you don't account for a number of other factors... like how flat and broad the torque curve is for the GS500........and redline is over 10K
Same for the HP curve....
the curves are fairly flat over like 2500 rpm range....so changing engine rpm like 300 or so is meaningless...
But I do agree with a couple of your premises:
Lower gear WILL give more torque when starting from a dead stop......Also WILL get heavy weight moving quicker.........this represents acceleration...and only applys to the BEGINNING of 1st gear.
But then again we don't really begin with a dead stop on the engine....we can rev up into the power band of the engine and transmit power smoothly via the clutch.......
But you are still missing two or three critical points in this discussion.........there is only one "power".....you can change the units of measurement...but power is power.....and power is torque times RPM.
You are also missing that as torque goes up, rpm goes down...(like when you use a lower gear) they don't both go up like you stated in your "honda on a dyno" statement above.
You are also not completly clear on engine power vs power at the rear wheel....
Lastly you are confusing "power" with acceleration........
But other than that we agree completly!! And thanks for presenting facts rather than personal attacks....
Cookie
please explain what i am not completely clear on, I have no ill will but you make statements with nothing to back them up other than "you are wrong"
your bike might have a higher speed but not be faster in any way, a 15T gs500 will kill a 16t
Quote from: crzydood17 on September 26, 2011, 06:27:29 AM
please explain what i am not completely clear on, I have no ill will but you make statements with nothing to back them up other than "you are wrong"
your bike might have a higher speed but not be faster in any way, a 15T gs500 will kill a 16t
well you have come up with some new kind of power...power is power period......power is torque time rpm..period....
shifting gears is simply a way to keep the engine in the power band.......I can put the engine into the power band in any gear (with the possible exception of 6th)
putting on a different gear ratio simply means that the shift points (relative to ground speed) are going to be different...that's all
The power of the bike is limited by the max HP of the engine........no matter how you gear it........
Lower gear does give (possible) advantage from a dead start....
Example of torque, power, rpm, and gear ratio:
My bike 16 th....your bike 15 th
we both are traveling at 50 mph....me in 6th gear....you in your (slightly lower) 6 th gear......
who is making more power to the rear wheel??
who is making more torque to the rear wheel
Who's engine is making more "power" (horsepower)??
Neither...they are both exactly the same!!!!
Now I shift down to 5th gear (slightly lower gear than your 6th)......keep speed at 50....
Who is making more HP to the rear wheel?
who is making more torque to the rear wheel?
Who's engine is making more HP?
Neither...they are exactly the same!!!
You and I can keep down shifting to lower and lower gears..........the torque and the hp at the rear wheel will not change as long as we keep the same speed.....
Of course at some low gear we will exceed engine redline RPM........that would be the limiting factor
cookie
if me and you are traveling 50 mph in 6th gear and floor it, who accelerates faster? Me,
if me and you are sitting at a redlight, we both launch at 3000 RPM who launches faster, me
If me and you are cruising at 50 mph and you look at our tachs mine will be higher, though i will be using less torque than you to keep the same speed because my gearing allows for my bike to be at that speed easier. Remember its a lever, my gear is moving faster but doing easier work, your gear is moving slower and doing more work.
Ok... crzy... here's where all the confusion is coming in...
The GS500 has HP of "X". And toque of "Y"
You said, "horsepower is only a function of torque". If that is the case - then - an increase in toque Must lead to an increase in HP as it is a function of torque.
Then, after much armwrestling we get this, "we are not discussing horsepower at the crank, this is why I do not call it horsepower it is merely power."
No, You (not we) are not discussing hp, you are discussing something else and You are calling that something else "power" and THAT throws everyone off, specially after saying, 'hp is a function of torque, I increased torque and increased power (but you didn't mean HP you meant the other thing you call power).
So how about this....
Lowering the front cog gives you Initial better acceleration and is less likely to lug the engine under load. We all agree on this. Forget the use of the word "Power". I am not going to read endless pages if information to figure out what You mean by the word power in this instance. This is a layman's forum where we don't all carry technical manuals in our head ready to decipher if the person meant power or Power or POWER or bippy dippies that imitate power.
In the end, if your 15 tooth front sprocket bike is up against a stock bike, all that will happen is... you will be off the line quicker and get "z" yards in front, at which point the stock bike will match you as it is now in the power band. And it will stay that way. Then in a vacuum, your 15th with peak out and the 16th will pull ahead. Anything to do with wind resistance making a difference on a bike like a GS with a 15 vs 16 front sprocket is to do with the rider and how much of a sail they make of themselves.
Arguing over "if I'm doing 50 and you are..." is pointless cause you/we can pick parameters to make our individual case the better... we can make up what rpm/gear either bike is in to make our own case the better. maybe opick a speed where the 15th is peak out and the 16 has some left, then you lose, but if it's a speed/gear combo that has the 16 peaked and the 15 one higher and some left, then we lose. In the end, we don't ride like this, we constantly change gears to give us the better mechanical advantage, as we deem fit at that moment.
After all is said and done: Lowering the front cog gives you Initial better acceleration and is less likely to lug the engine under load. So now can we move on?
Michael
not exactly, the 15t will pull the 16t till the end of 6th gear where in a vacuum yes the 16t would pull ahead but until then the 15t is always going to be quicker. But everything else you said is correct and I agree. Remember the internet is serious business.
Quote from: crzydood17 on September 26, 2011, 08:01:38 AM
if me and you are traveling 50 mph in 6th gear and floor it, who accelerates faster? Me,
if me and you are sitting at a redlight, we both launch at 3000 RPM who launches faster, me
If me and you are cruising at 50 mph and you look at our tachs mine will be higher, though i will be using less torque than you to keep the same speed because my gearing allows for my bike to be at that speed easier. Remember its a lever, my gear is moving faster but doing easier work, your gear is moving slower and doing more work.
Ok let's use this example.....you and I are traveling at 50.....me in my sixth, and you in a lower sixth...
We floor it...but I shift down to 5th...you stay in sixth...who wins???
Cookie
you two need to get a room.
XXXXX
Quote from: ojstinson on September 26, 2011, 04:50:43 PM
you two need to get a room.
If this discussion is of no interest to you then don't read it....... :nono:
Cookie
Quote from: twocool on September 26, 2011, 03:45:51 PM
Ok let's use this example.....you and I are traveling at 50.....me in my sixth, and you in a lower sixth...
We floor it...but I shift down to 5th...you stay in sixth...who wins???
Cookie
Mr. Cookie, what you've just said is one of the most insanely idiotic things I have ever heard. At no point in your rambling, incoherent question were you even close to anything that could be considered a rational thought. Everyone in this room is now dumber for having listened to it. I award you no internets, and may God have mercy on your soul.
Quote from: crzydood17 on September 27, 2011, 06:48:21 AM
Quote from: twocool on September 26, 2011, 03:45:51 PM
Ok let's use this example.....you and I are traveling at 50.....me in my sixth, and you in a lower sixth...
We floor it...but I shift down to 5th...you stay in sixth...who wins???
Cookie
Mr. Cookie, what you've just said is one of the most insanely idiotic things I have ever heard. At no point in your rambling, incoherent question were you even close to anything that could be considered a rational thought. Everyone in this room is now dumber for having listened to it. I award you no internets, and may God have mercy on your soul.
I guess that question was a little too hard for you? And I tried to use small words.
Answer: In acceleration, your sixth beats my sixth.....my fifth beats your sixth...your fifth beats my fifth, etc....
Until we either get to redline engine RPM.... or 1st gear.......
See, the "middle" gearing doesn't matter....only matters starting off in 1st or top end in sixth.......
Power comes from the engine, not the gearing.........
I'm sure this makes no sense to you whatsoever!!!
But we never even got past the simple term "power"....
You never studies HS physics Huh? But then again...you can't teach calculus to an ant either...
Ignorance is bliss..
Personal attacks? Ok whatever... End of conservation...
Cookie
Moderators.......please.......to the tard farm....please.........it's hopeless!!
so your saying that in the same gear if we raced no matter what gear my bike would win...
if we raced from a dig you in 1st and me in 6th who would win? WTF ARE YOU THINKING HERE OF COURSE YOU WIN IF YOU DROP A GEAR... Thats like saying if I bring a gun and you bring a knife who shoots first... :2guns:
MODS, do NOT TF this thread.
Cookie wants to keep on going and going and going and then wants it TFed, as if it's his personal goal to TF threads that don't go his way or go off topic or something. He seems to suggest tard farming threads a lot. I think he has a fetish or something :dunno_black:
Leave it how it is, there is some quite good level headed discussion in it.
Michael
Quote from: crzydood17 on September 27, 2011, 06:58:21 PM
so your saying that in the same gear if we raced no matter what gear my bike would win...
if we raced from a dig you in 1st and me in 6th who would win? WTF ARE YOU THINKING HERE OF COURSE YOU WIN IF YOU DROP A GEAR... Thats like saying if I bring a gun and you bring a knife who shoots first... :2guns:
Jeeze...I though I was going to give up on this...but you answered without personal attack...so let's keep going! :thumb:
No...I am saying you must use the correct gear which produces the most engine HP (keeps the engine in the power band ..high rpm.....this is why GS has 6 gears to select from.... Only difference from 16 th and 15th this is in first and 6th..........for "performance" with either gearing, we would use the same shift points relative to engine RPM...(top of the power band) but the shift point would be at different rear wheel rpm (road speed)....
For maximum acceleration.....A low first gear WILL give somewhat (but little) advantage from a dead stop....also a slight advantage if the bike is overweight...
In top gear (6th)...a lower gear ratio Might be an advantage....IF you are going at really high speeds....and IF you wnt to run the engine up to near or at redline......(as in racing on a track)....
But back to reality.....most of the time we are not "drag racing" so the low first gear is not much help.....most of us don't rev the engine up into the power band and release the clutch (what would be needed to extract max engine HP and give the fastest acceleration....)
Most of the time we are already in second gear or higher...(my weekend commute has only three stops in 80 miles)
Most of the time we are not at top speed (engine rpm or road speed) in 6th gear.....most prefer to use 6th gear as a sort of over drive.....to bring engine RPM down to a comfortable level...vibration, noise, and for gas economy....(we normally don't need a lot of torque at cruising speeds...and at these road speeds you simply down shift to a lower gear if acceleration is needed.....(six gears, remember?)
Now if we are talking about Racing on a specific track....(which we're not)..then you must keep the engine in the power band at all times........like around the 8000 to 9500 RPM range....some say you must always run up to redline before shifting to a higher gear.....And you're gonna choose a gear ratio which will allow the engine to just barley hit redline in top gear at the end of the longest straight.........But this is totally impractical for road riding...
But reality....we ride the road...we are out to enjoy the ride....we are not trying to win some imaginary race with each gear shift.....
The gear ratios chosen by Suzuki on the GS are a compromise....but the best of all worlds.....First gear is plenty low enough...and top gear is plenty high...and you have 4 more in the middle to choose from...
But "power" is produced by engine ..and we measure it in Horsepower....and the "power" to the rear wheel is also Horsepower...and it is simply the RPM x torque.........the power to the rear wheel is determined by the power produced by the engine.........Gearing cannot produce, nor change power.........Toque at the rear wheel goes down, as road speed (rpm) goes up...regardless of what gear you are in! (provided you keep the engine at the max power band....
All gearing does is allow you to keep the engine at its maximum power range (rpm) through a variety of road speeds.........If you desire maximum acceleration, this in only possible at max engine power......so we choose a gear (1st thru 6th) which puts the engine into the RPM range of max power) (usually requires down shift). But for road riding most of us ride at engine PPM far bleow the power band....like shifting at 6000 or 7000...not running up to 10,000.....
You like 15 th? Ok fine........works for you........but more power? Nope!
Cookie
Quote from: mister on September 28, 2011, 03:55:40 AM
MODS, do NOT TF this thread.
Cookie wants to keep on going and going and going and then wants it TFed, as if it's his personal goal to TF threads that don't go his way or go off topic or something. He seems to suggest tard farming threads a lot. I think he has a fetish or something :dunno_black:
Leave it how it is, there is some quite good level headed discussion in it.
Michael
Michael.....when the personal attacks start....the thread is worthless.........to the tard farm!
(and I noticed the personal attack in your post above)
If somebody wants to discuss.....ok discuss.....we can disagree with out personal attacks.....point /counter point.......a lot can be learned this way....or we can run a thread for years and get nowhere...whatever....
Old "crazy- what's his name" makes some interesting points.....but also (IMO) has a couple of misconceptions about the physics behind gearing....(power, torque, RPM, force, work, etc)
It's hard enough to explain things on this type of chat group, and even harder when the thread degrades to personal attacks........
But there are some typical arguements, which occur over and over on these chat groups..and you know that nobody is going to change their opinion...and you know it is going to degrade to personal attacks...and you know the whole exersize is pointless....
So the tard farm is a good place for this crap!
If you remember this thread is actually about trying to ride a GS over gross weight?
Problem ....solution...
Problem..over gross weight .....
Solution...
don't ride over gross, get biger bike
Proposed solutions:
Get bigger shock
Get lower gearing
The proposed solutions don't completly address the problem.....
Cookie
if you can't understand it I can't explain it any more.
Gears produce more torque period end of question there is no way to argue that and if you can't accept it then its your problem.
Horsepower is a mathematical equation of torque, it can be considered torque over time. If a gear ratio increases torque then it increases Wheel HP, not Crank HP.
In all gears, a 15T puts the bike higher in the RPM for a given speed by about 500-600 RPM, Shy of the super rare times when my bike would be at redline and yours would be 500 from red line there is no instance where the 16T can match the performance of the 15T, and its far from a minor change.
You pull out of the argument by saying "normally" well if we are discussing normal driving here's the spill on the 15T
1. My starts are smoother and easier on the engine and clutch because I don't need as much RPM to move the bike.
2. My gas mileage in town is better because the ease of starting from a stop which is what uses the most gas.
3. My highway mileage is barely affected because it is only a minor increase in RPM combined with a easier time turning the rear wheel.
4. Unless I am in 6th, I can always move up a gear and drop my RPMs to the 3500-5000 range.
What is the advantages of the 16T?
1. Slightly less wear on the chain.
2. Slightly less RPM on the highway
You can argue till your blue in the face, These are facts I bring instead of false conjecture.
Quote from: crzydood17 on September 28, 2011, 05:13:12 AM
if you can't understand it I can't explain it any more.
Gears produce more torque period end of question there is no way to argue that and if you can't accept it then its your problem.
Horsepower is a mathematical equation of torque, it can be considered torque over time. If a gear ratio increases torque then it increases Wheel HP, not Crank HP.
You pull out of the argument by saying "normally" well if we are discussing normal driving here's the spill on the 15T
1. My starts are smoother and easier on the engine and clutch because I don't need as much RPM to move the bike.
2. My gas mileage in town is better because the ease of starting from a stop which is what uses the most gas.
3. My highway mileage is barely affected because it is only a minor increase in RPM combined with a easier time turning the rear wheel.
4. Unless I am in 6th, I can always move up a gear and drop my RPMs to the 3500-5000 range.
What is the advantages of the 16T?
1. Slightly less wear on the chain.
2. Slightly less RPM on the highway
You can argue till your blue in the face, These are facts I bring instead of false conjecture.
Oh...I understand it...It is you who doesn't so I have to keep explaining.....(just joking...let's continue to discuss...we are getting closer agreement...believe it or not..
Let's start with your first sentence:
"Gears produce more torque period end of question there is no way to argue that and if you can't accept it then its your problem."
Gears do not produce "more" (or less) torque........(changing gears may or may not change torque, as would changing engine power...(throttle and rpm rlelative to the power band) engine power thru the drive chain to the rear sprocket to the wheel produces torque. By changing gears. ....or selecting certain gear...we can change the torque at the rear wheel. Again you are not taking into account the factors involved...you talk about gears (I think you mean gear ratio) and torque....but you are leaving out wheel RPM....and engine RPM power band).
Next paragraph........"Horsepower is a mathematical equation of torque, it can be considered torque over time. If a gear ratio increases torque then it increases Wheel HP, not Crank HP. "
Horsepower is not an equation of torque.....torque is one of three factors in Hp....Torque over time is not HP either...(that would be called "work"....now you're up to two of the three parameters...
HP is a factor of Time, distance, and force........in rotation (like a rear wheel) the Time is still time....the force is Torque....and the distance is how far the wheel rolls.......
We usually substitute RPM (which is time and distance together)...so HP at he rear wheel is torque, time, RPM (torque time and distance)
If I travel at a constant speed.....then the rear wheel rpm is constant..therfore the torque to the rear wheel is constant, and the HP to the rear wheel is constant..NO MATTER WHAT GEAR I HAVE SELECTED!
This is basic fizziks! you surely have the basic idea...but not complete...Hard to go further until you understand the terms and how they effect what we are talking about..
Cookie
C-dood,
You say the following:
on the 15T
1. My starts are smoother and easier on the engine and clutch because I don't need as much RPM to move the bike.
2. My gas mileage in town is better because the ease of starting from a stop which is what uses the most gas.
3. My highway mileage is barely affected because it is only a minor increase in RPM combined with a easier time turning the rear wheel.
4. Unless I am in 6th, I can always move up a gear and drop my RPMs to the 3500-5000 range.
What is the advantages of the 16T?
1. Slightly less wear on the chain.
2. Slightly less RPM on the highway
15 th:.....
Point one: I agree! (as I keep saying, changing to lower ration only effects starting form a dead stop)
Point two: I agree! Again starting from a dead stop.....
Point three: I agree: Barely affected...Ok but affected negatively (butif your physics was correct you'd drive on the highway in 5th gear and never use sixth...
Point 4: This has to do with top gear...I agree........(again I hae said all along that the difference in sprocket only has an effect on 1st and 6th gear........
16 th....
Point one: I agree
Point two: I agree
Point three: better mileage....
Point four: To me....(personal opinion) the advantages of the 15 th are very small to immeausrable..........The benefits to the 16th although tiny....are better mileage, and lower engine RPM at cruise out weight any slight benefits of 15th. I do not ride in city much at all.....
In gears 2, 3, 4, 5, it doesn't matter one bit...........
You see it the opposite...OK ....
But I'm not trying to agrue with you about whether a 15 th is better or a 16th.......
I am trying to argue with you about your (IMO) misunderstanding of the Physics involved.
Let me pose another question to you........If the 15th is so much better in every way, why did Suzuki install a 16 th?
Cookie
Lets say I have a motor that produces 200nm torque at 4000 rpm, this is the output of the motor not at the wheels, I could stick a one million tooth sprocket on it or a 2 tooth sprocket, at 4000 rpm I'm still only making 200nm of torque, sure the bike won't want to move at all with the million tooth sprocket yet at that rpm it still makes that much torque, its just the load encounted that is higher
A better example might be, ever rode a push bike with gears, well ure pretty much the engine on the bike, when u Changed to the big sproket on the front it became harder for you to move the bike uphill right, although you covered more ground for the same a mount of rotationsyet the smaller front sprocket made the ride uphill a bit Easter yet covering less ground, you as a person still were the same, the bigger sproket didn't make u weaker, just changed the way u applied the power and torque u had
I put a 15T front sprocket on my 97 GS early on and liked it. Weighing about 240# at the time it made starting on uphill grades easier and smoother and felt a bit more powerful all around particularly on the mountain trips I use to take back when I was a young man of about 70.
When I replaced the 97 GS with my current 02 GS with the 3 circuit carbs replacing the 2 circuit carbs I felt no need for the 15T front sprocket and rode it for over 85k miles with stock gearing, just turned 90k miles yesterday. :thumb: This spring I put a 15T front sprocket on and like it very much after running the summer with it. But, I'm currently running a 140/70 AM26 rear tire that has a 25.2" published dia and the bike came with a 24.1" dia Excedra rear tire. 24.1/25.2x16=15.3 so I guess I just got back to stock gearing overall with my 02 GS and Suzuki was not too far off with their choice. :icon_lol:
I still maintain the original poster is not too far off with his 420# load and a larger rear tire would put his bike's load rating above that amount. Anyhow, bikes and other vehicles come with gearing suitable for the average user under average conditions and your personal needs may require some fine tuning.
Damn, even though you have not said why, I am wrong about horsepower at the rear wheel.
Horsepower does not go up at the rear wheel even though torque does. Here is a proof,
(WRPM = Wheel RPM)
50 ftlbs of torque at 7500 RPM = ~ 71 HP and 50 Ftlbs at 7500 WRPM
50 ftlbs of torque at 7500 RPM / a 2:1 ratio = ~71 HP and 100 Ftlbs at 3750 WRPM
Since the RPM does not stay constant and is divided by the gear ratio, the Horsepower number stays the same and the torque is multiplied by the gears.
So I give that Horsepower does not go up at the rear wheel even though torque does.
Now its merely a argument of what the definition of power is... and I feel that is to each his own, so, I enjoyed this, I love a good argument and its fun to learn stuff!
Yes its what is known as the torque ratio, however the mtor makes the exact same a mount or torque and power, its just applied differntly. Its the entire point of a gearbox, yet u don't here of people changing gearboxes to make more torque
Quote from: crzydood17 on September 28, 2011, 06:48:00 AM
50 ftlbs of torque at 7500 RPM = ~ 71 HP and 50 Ftlbs at 7500 WRPM
50 ftlbs of torque at 7500 RPM / a 2:1 ratio = ~71 HP and 100 Ftlbs at 3750 WRPM
Since the RPM does not stay constant and is divided by the gear ratio, the Horsepower number stays the same and the torque is multiplied by the gears.
Nice numbers.
To put it in terms that maybe more people can understand, lets talk "levers", in the non-rotational world.
Lets say you have a 2ft lever, and you're trying to apply force to something to move it. You are able to apply 100lb of force , applied over some fixed amount of movement space.
If you change to using a 4ft lever/crowbar, you may be able to apply an effective amount of 200lb of force, but you'll only be able to move the thing 1/2 as far, if your amount of movement space stays the same. You dont get something for nothing.
Moving back to the rotational wheel world:
acceleration capability = torque.
If you change to the "2:1 ratio", you'll get a buttload more torque, so muchmuch more acceleration.... but you'll only be able to apply it for about half the speed.
So whereas before, the gear may take you from 0-20, now it will only take you to 0-10 before the engine redlines.
A gearing with massive amounts of torque, that is only usable within a range of x-(x+10) mph, is not that useful a thing :-)
the GS500 is theoretically capable of hitting 130mph.
If you are interested in aceleration only within mostly legal ranges, then it might be worth while to change up the gearing for our GS500s, so that it tops out at ... 80mph?
Quote from: crzydood17 on September 28, 2011, 06:48:00 AM
Damn, even though you have not said why, I am wrong about horsepower at the rear wheel.
Horsepower does not go up at the rear wheel even though torque does. Here is a proof,
(WRPM = Wheel RPM)
50 ftlbs of torque at 7500 RPM = ~ 71 HP and 50 Ftlbs at 7500 WRPM
50 ftlbs of torque at 7500 RPM / a 2:1 ratio = ~71 HP and 100 Ftlbs at 3750 WRPM
Since the RPM does not stay constant and is divided by the gear ratio, the Horsepower number stays the same and the torque is multiplied by the gears.
So I give that Horsepower does not go up at the rear wheel even though torque does.
Now its merely a argument of what the definition of power is... and I feel that is to each his own, so, I enjoyed this, I love a good argument and its fun to learn stuff!
Ok...I agree...........at the rear wheel ....torque and wheel velocity (rpm) are inversely proportional.......so if you double the torque, you halve the RPM....or if you double the RPM you halve the torque........
The power (horsepower) does not change because hp = Torque x rpm...
let me see if I can clear up some additional confusion between us....
I think you are sometimes using the term "power" when you should be using the term acceleration.
Let me give a couple of examples:
It takes power to make a motorcycle move......force x distance x time = power
At a given speed (say 50 mph) there are forces counteracting the motorcycles forward movement....largely air drag, but also mechanical friction, and tire friction.
The power of the engine is transferred (ultimately to the tire, and then to the road) to produce a resulatant (forward) force in the direction of travel........if this force is equal to the resisting forces (drag), the motorcycle will maintain a constant speed...all forces are in balance...
Interesting fact about power required.........since drag is a function of the square of the speed...in order to go twice as fast, it requires the engine to develop 4 times the power!!! Example....motorcycle is "flat out" and is going at 100 mph...engine is producing say 40 HP......if you slow to 50 mph.....the engine only needs to produce 10 HP......at 25 MPH only a little over 3 HP. If you wanted to go 200 MPH you would need to go from 40 HP all the way up to 160 HP...
Yes this is just theoretical for example as many other factor have been left out...
Now back to acceleration...this is when we CHANGE speed...typically from a slower speed to a faster speed...or even from stopped to moving....
In order to accelerate we need to add power!! (engine power) Because as we go faster, drag increases..and we need more forward force to overcom this drag.....the only way is to increase the output at the engine...at this new , increased power setting...the bike will accelerate from the slower speed up to a faster speed....but then the speed will remain constant at this new faster speed...because the forward forces from the engine power to the road, are now equal with the drag forces.
(I know this is getting long...stick with me....I'm getting to the point eventually...)
Now we have to look at the RATE of acceleration...in other words 0 to 60 MPH is an increase in speed...an acceleration...but 0 to 60 in ten seconds is the RATE of acceleration...0 to sixty in 5 seconds would be the same change in speed...but the change happens twice as quickly.....
The HP required to double the rate of acceleration is 8 times!!!! (third power)
So...if my 40 HP bike goes 0 to 60 in 10 seconds...I would somehow have to get 8 times the HP to go 0 to 60 in 5 seconds.......(320 HP) Holy crap.........
This is why drag racing cars and bikes have huge HP...Like in the thousands......to do like 4 second 1/4 mile 0 to 300 MPH....
(Almost to the point)
OK so I want to accelerate at the maximum rate with my little GS 500 with 42 HP......
The only way to do that is to keep the engine making the full 42 HP...(less hp means less acceleration......an ther is no way to get more than 42 HP)
The only way to do that is to find the RPM which produces the most (42 Hp).. and it's way up there...I don't have the chart but it's like close to redline, if not redline...10,000 ??
OK...now here is where gearing comes in..........if I chose a to big of a gear.....the engine will not be able to stay at optimum RPM for top power..the engine slow, (bog down) to below the power band...less power to the wheel...slower (or no) acceleration........
So I choose a smaller gear to accelerate..by using first gear from a dead stop..or down shifting when crusing and wanting to accelerate...
But what is the limit to how small of a gear? Engine redline...
If I want maximum rate of acceleration, I must keep the engine as near to redline as possible without going over.........
Also, say I'm curising at 50 mph 6 th gear the engine is turning like 4000 RPM......the engine is not producing very much HP at this low engine RPM......If I want to accleerate to a higher speed...I can open the throttle but the acceleration will be poor at best...becuase I'm not making much HP at the engine............(engien way slower than the power band)
So what am I gonna do? I'm gonna down shift to 5th, or maybe even 4th....get that engine up to 7000 or more.....I still have to open the throttle wide to make HP too....now the bike will accelerate nicely...because the engine is making more power......
Now if you want to talk torque...we could say the by down shifting, we are adding torque to the rear wheel.........BUT DOWN SHIFTING ALONE DOES NOT ADD ANY TORQUE AT ALL......DOWNSHIFTING ALLOWS THE ENGINE TO SPIN FASTER, WHICH GENERATES MORE ENGINE HP WHICH DELIVERS MORE POWER TO THE REAR WHEEL.. YOU HAVE TO DOWN SHIFT AND ADD THROTTLE!!!
In choosing a lower gear, we are also relieving some torque from the engine, allowing the engine to speed up.........The "magic" here is the nature of piston engines...as they speed up, they produce both more HP and more torque...at high revs the torque drops a bit but HP keeps going up....
As engine HP goes up, so does power to the rear wheel, so does the bikes speed, and so does the acceleration....
So the point (finally) is that POWER is needed to move.....more POWER is needed to move faster, and even more POWER is needed to accelerate..........
A piston engine makes it's most power at high rev's..........
We simply use gear ratios in order to keep the engine reving high (if we want to go fast or accelerate quickly)
Cookie
Quote from: Phil B on September 28, 2011, 09:49:04 AM
Quote from: crzydood17 on September 28, 2011, 06:48:00 AM
50 ftlbs of torque at 7500 RPM = ~ 71 HP and 50 Ftlbs at 7500 WRPM
50 ftlbs of torque at 7500 RPM / a 2:1 ratio = ~71 HP and 100 Ftlbs at 3750 WRPM
Since the RPM does not stay constant and is divided by the gear ratio, the Horsepower number stays the same and the torque is multiplied by the gears.
Nice numbers.
To put it in terms that maybe more people can understand, lets talk "levers", in the non-rotational world.
Lets say you have a 2ft lever, and you're trying to apply force to something to move it. You are able to apply 100lb of force , applied over some fixed amount of movement space.
If you change to using a 4ft lever/crowbar, you may be able to apply an effective amount of 200lb of force, but you'll only be able to move the thing 1/2 as far, if your amount of movement space stays the same. You dont get something for nothing.
Moving back to the rotational wheel world:
acceleration capability = torque.
If you change to the "2:1 ratio", you'll get a buttload more torque, so muchmuch more acceleration.... but you'll only be able to apply it for about half the speed.
So whereas before, the gear may take you from 0-20, now it will only take you to 0-10 before the engine redlines.
A gearing with massive amounts of torque, that is only usable within a range of x-(x+10) mph, is not that useful a thing :-)
the GS500 is theoretically capable of hitting 130mph.
If you are interested in aceleration only within mostly legal ranges, then it might be worth while to change up the gearing for our GS500s, so that it tops out at ... 80mph?
Yes! The only way to accelerate is the add excess torque to the wheel....there is a certain amount of torque at the wheel just to maintain speed...if you increase this torque you will increase speed....(accelerate)
The only way to increase the torque is to increse engine power (or slow the wheel)
You can use down shifting to slow down...........(close throttle, shift down...torque goes up at rear wheel and speed goes down...bike slows down..engine produces less power..
You can use down shift to speed up...open throttle, shift down, torque goes up, speed goes up, because engine is makeing more power....
Ultimately the difference between slowing or speeding up is engine power, not gearing...as the example above shows.....
Quote from: twocool on September 28, 2011, 09:56:32 AM
The only way to do that is to keep the engine making the full 42 HP...(less hp means less acceleration......an ther is no way to get more than 42 HP)
I've read a claim that for a stock GS500, max torque is at around 7.5k, but max HP is around9k rpm.
(but if you change gearing, those peaks will change, presumably!)
Sounds odd that it would have different peaks.. but in the Real World.. hey, it's what happens. Otherwise, dyno graphs would not bother to separately graph torque and HP output, right?
and at extremes, any physical mechanism will tend to lose efficiency. So, remember, redline is not "max output". redline is "happy parts about to get no happy; you are exceeding efficient spec, and when efficiency degrades enough, engine will blow up".
redline is not your friend :D
Quote from: Phil B on September 28, 2011, 10:10:17 AM
Quote from: twocool on September 28, 2011, 09:56:32 AM
The only way to do that is to keep the engine making the full 42 HP...(less hp means less acceleration......an ther is no way to get more than 42 HP)
I've read a claim that for a stock GS500, max torque is at around 7.5k, but max HP is around9k rpm.
(but if you change gearing, those peaks will change, presumably!)
Sounds odd that it would have different peaks.. but in the Real World.. hey, it's what happens. Otherwise, dyno graphs would not bother to separately graph torque and HP output, right?
and at extremes, any physical mechanism will tend to lose efficiency. So, remember, redline is not "max output". redline is "happy parts about to get no happy; you are exceeding efficient spec, and when efficiency degrades enough, engine will blow up".
redline is not your friend :D
Here is where it gets a little flaky....
Most if not all piston engines put out max torque (engine torque) at mid-high RPM...while max HP at really high RPM......I don'tknow exactly why, but this is true for engines....
But here is a point which I have been trying to make all along......Hp is torque times RPM....
Torques is only one piece of the HP...RM is the other.........
So even though the torque peaks at 7500........the HP continues to climb higher with additional RPM...(sometime drops a bit at or very near redline)
"Max output" would be Max horsepower....not max engine torque.....
Don't confuse max torque at the rear wheel, with max torque at the engine.....
Max torque at the rear wheel can only be achieved at max engine HP.......(combined with the proper gearing)...actually an incredibly low 1st gear would give tremendous wheel torque...and would only go a fraction of one mile per hour with the engine screaming....
Earlier I posted a link to a car racing guy who explained how you have to shift at redline to get the best acceleration, not shifting at best (engine) torque...........
Cookie
Quote from: twocool on September 28, 2011, 10:21:32 AM
Earlier I posted a link to a car racing guy who explained how you have to shift at redline to get the best acceleration, not shifting at best (engine) torque...........
Cookie
well that's a whole nuther thing. that's about sports strategy, practical uses, and human reaction times, blah blah.
You dont shift AT "best" output. You want to *USE* that output :-) So you shift after you've "used up" the best part.
Plus, it's also a matter of what you are shifting
to. Odds are, the gear you are shifting to, would not be at peak output. So even though your current gear is past its peak, its still better than the alternative, until somewhere around redline, where the next gear will then be getting close to its own peak.
PS:
http://gstwin.com/dyno_run.htm
Quote from: Phil B on September 28, 2011, 10:28:01 AM
Quote from: twocool on September 28, 2011, 10:21:32 AM
Earlier I posted a link to a car racing guy who explained how you have to shift at redline to get the best acceleration, not shifting at best (engine) torque...........
Cookie
well that's a whole nuther thing. that's about sports strategy, practical uses, and human reaction times, blah blah.
You dont shift AT "best" output. You want to *USE* that output :-) So you shift after you've "used up" the best part.
Plus, it's also a matter of what you are shifting to. Odds are, the gear you are shifting to, would not be at peak output. So even though your current gear is past its peak, its still better than the alternative, until somewhere around redline, where the next gear will then be getting close to its own peak.
PS:
http://gstwin.com/dyno_run.htm
Yep...like most things...it all depends......what are you trying to accomplish at that moment....
I'm just giving examples of "what if" like what if you want the fastest possible accelleration? or what if you want the fastest lap time...No real world application of this for me...
I don't race...I don't drive particularily fast............I don't make jack rabbit starts......I like fuel economy........I typically shift at 5000 to 6000.....on rare occasions up to 8000 like if passing....
I curise in the 4000 to 5000 range...
I am not using anywhere near the HP available ..stock gearing works fine for me...
Life is good!
Cookie
holy crap this thread is still going, twocool you still aren't getting the horsepower formula right torque*rpm/5252
wow... i thought i was a persistent arguer but damn twocool you make me look like france...
Quote from: crzydood17 on September 28, 2011, 08:09:41 PM
holy crap this thread is still going, twocool you still aren't getting the horsepower formula right torque*rpm/5252
wow... i thought i was a persistent arguer but damn twocool you make me look like france...
OK...You're right on hP.....It has a "constant" in the formula.. 5252.........(but only if you use lb-ft for torque..........
All this does is determine the "units" of measure...such as HP vs Kilowatts..........
I was just trying to show you that you were confusing torque with power............
The general formula for power is force x time x distance for straight line.....or..
Torque x RPM for rotation..........notice I did not specify any units of measurement.........I could be "miles-hours-tons"....or any other units you dream.........
HP has a very specific definition and a constant.....(even though you earlier said that HP was NOT a specific term and was not used widely)
In your earlier posts you came up with torque = power which is not correct....
You also made this statement:
"Horsepower is a mathematical equation of torque, it can be considered torque over time. If a gear ratio increases torque then it increases Wheel HP, not Crank HP. "
I said no......hp is not an "equation of torque"...I also pointed out that HP is not torque over time either.............
HP is torque x distance x time........or torque x RPM (since RPM contains both time and distance)
So OK put in the constant to keep the units straight
But let's be clear on what we are arguing about (at least what I am arguing about)...
I contend that a 15 th sprocket will only help (Slightly) only at the begining of first gear.....and there will be no performance difference is all the middle gears, with either sprocket...until possibly 6 th gear...........
I contend that you are mistaken...thinking that the bike will produce more "power" in "every" gear if you lower the sprocket to 15..........
I contend that you are confusing the term "acceleration" with the term power....
I'd most certainly like to agree with you...but then we'd both be wrong!!
And.....It's been raining all week......rain for me means no work...no riding...too much spare time!
Cookie
lol .. While the combatants were busy composing the trilogy in 9 parts .. I went for a ride .. It was a warm sunny day .. And it was fun
(http://cdn.thegloss.com/files/2010/10/someone_is_wrong_on_the_internet1.jpg)
(http://www.motifake.com/image/demotivational-poster/0911/jean-luc-jean-luc-amused-demotivational-poster-1259093717.jpg)
(http://s1.static.gotsmile.net/images/2011/04/30/1632-dont-worry-mam-were-from-the-internet-cosplay_130419257969.jpg)
(http://www.myconfinedspace.com/wp-content/uploads/2009/05/dont-argue-with-me-ive-been-on-the-internet-500x375.jpg)
(http://images.ridemonkey.com/index.php?size=full&src=http%3A%2F%2Ft3.gstatic.com%2Fimages%3Fq%3Dtbn%3AANd9GcTaRavwEc2093FGGfc2ZaQuG7xmeMdiC1XesOHRzh-XkUotKNtr)
snort chuckle chortle HaHahaha