I was thinking about this while manuvering around some manholes today and noticed it is really flickable like everyone says.
Now I hear that with bigger more powerful bikes it takes much more effort to turn or lean (flick) the bike. But I know also that alot of the bigger more powerful bikes are also lighter that the GS 400 lbs. Sooooo...
To those who have riden or have bigger bikes:
Question: If they are lighter shouldn't it be easier to move them than the GS?? Enlighten me Please
It's a combination of things. Light weight. Upright bars that you can put a lot of torque on, and skinny ass tires.
Steering geometry and center of gravity, too. Wide bars help leverage the entire package over.
Moment of inertia from the rotating mass ... crank, transmission gears, wheels, pistons and cams.
Cool.
Srinath.
The EX250 is more flickable due to 25% weight reduction, but the steering geometry is more stable so it wants to stand up in the corner. My 05F takes a little more nudge to counter it in, but it is almost dead neutral in the corner so you don't have to lean on the bars to hold a line.
Good answer, Srinath. Less rotating mass in the engine.
Also, I have never really looked at this on the GS, but many manufacturers are putting the crank on the same plane (ie., height) as the axels. This is supposed to help with the effect you've described. Has anybody got any theories on that.
Engine height changes when in a corner, but I think inital turn-in is where all three need to be in-line, thus the change in direction is a smoother transition. GSXR1000 has 17" front and rear rims but different sized tires front vs. rear, so in a level view, the axles are on different planes, but if you draw a straight line between the axles, that line should go through the crank. Another thing to look at is when braking for a turn the engine crank is going to be lower, because of the front suspension being compressed; it should still be inline with the rear axle, though.
I noticed the GS handled better than my SV (or felt more tossable). I assumed it was a weight issue, but rotating mass is much more likely as my z1000 hates to flick into turns -I have to romance the damn thing to get it to drop into a turn.
Ok, now I'm beginning to think that because of the greater mass of the bike, the greater the braking needed, which induces more dive, the more out of whack the front axle is going to be in relation to the crank and rear axle, if you draw a line from the rear axle, through the crank and into the ground behind the front tire.
As someone who has only ridden a GS, this is very interesting. So while the GS can effortlessly be dropped into a turn and will hold that line through it with pretty much no additional input from the rider, other bikes need you to continue applying additional pressure to the inside handlebar to keep it dropped into the turn? Is that more or less what people are saying?
Dave
What I am saying is it takes much more strength and effort to get a z1000 to drop into a turn -lots of steering input and body english.
I have to apply pressure on the inside grip to keep my GS leaned over, but that's because I'm not throttling through the turn. Also, it could be the 1mm that I have the fork tubes down through the tripleclamps, the 3/8ths inch preload on the stock springs.
Quote from: scratch on April 11, 2006, 12:59:37 PM
I have to apply pressure on the inside grip to keep my GS leaned over, but that's because I'm not throttling through the turn. Also, it could be the 1mm that I have the fork tubes down through the tripleclamps, the 3/8ths inch preload on the stock springs.
Yeah, you have to apply pressure to keep turning, or you'll straighten up. I'm not saying this right, and I know I won't this time either. What I'm hearing is that it takes more effort to drop other bikes into turns, and still more effort to keep them turning, correct? As opposed to the GS, which can be tossed into the corner and will maintain that line without a lot of effort.
Again, I probably said that wrong. I'm just trying to figure out what people are saying exactly.
fg3
It is true on Motoguzzis.
[34
When you roll on the throttle on a Motoguzzi, the bike likes to roll to the right.
Oh, and the Goldwing crank is parallel.
s1
it takes more effort on SOME bikes.
QuoteHow do you get a flat 6 into a bike with the crank rotating parallel to the frame?
parallel in relation to front to rear of the bike. Goldwings are so damned heavy they dont flick one way or another under natural conditions. the only un natural condition that comes to mind involves explosives and a cliff side.
Quote from: Wrecent_Wryder on April 11, 2006, 03:20:27 PM
Quote from: scratch on April 11, 2006, 02:57:42 PM
When you roll on the throttle on a Motoguzzi, the bike likes to roll to the right.
Well, that would be enough to disqualify a bike from my consideration...
It's not that much.
Quote
Oh, and the Goldwing crank is parallel.
How do you get a flat 6 into a bike with the crank rotating parallel to the frame?
Quote
Parallel
with the frame, lengthwise.
Torque effect on Guzzi's and Beamers and Gold Wings and what not is pretty minimum. It doesn't interfere with anything, but in a neutral standing you'll be able to notice.
Quote from: phire on April 11, 2006, 06:03:16 PM
Quote from: AlphaFire X5 on April 11, 2006, 10:37:54 AMass tires.
Where do I get these ass tires you speak of?
(http://www.bikernet.com/news/images/PhotoID10777.jpg)
Perhaps?
:o Nice soft tail.
Gotta get me some ass tires.
I think it is the width of the wheels. People have mentioned the big bikes being harder to turn, they have fatter wheels. I think also the length of the bike has an effect because scooters turn very quickly.
Quote from: ukchickenlover on April 11, 2006, 10:40:13 PM
I think it is the width of the wheels. People have mentioned the big bikes being harder to turn, they have fatter wheels. I think also the length of the bike has an effect because scooters turn very quickly.
Exactly. Skinny ass tires.
Some of you have touched on rotating mass...that's the biggest contributor to a loss of "flickabillity". My TL, for example, has 3" and 6" wheels with much beefier hubs and spokes, bigger brakes and, of course, bigger rubber. This added weight to the spinning assembly is tremendous at speed and increases the gyro effect (the gyro effect is what causes the wheels' resistance to tilting).
The second largest drain is crankshaft size and configuration. A 1000cc I4 crank is going to be bigger and heavier and have a more dramatic gyro effect than the crank in 400cc I4...but the crank in my TL1000S (996cc 90* V-Twin) is smaller and lighter than the one in a 600cc I4.
Next we have the engine's location. Having the crank mounted above the axle line will create a lot of dead weight at speed and will make the bike easier to "fall in", but more difficult to recover. The increased weight of the engine assembly acts as a lever against the gyros (wheels), but returning to upright you have to fight the same lever. Mounting the crank below the axle line will make the bike require more effort to fall in, but returning to upright will be sharper. Most manufacturers of sport bikes try to mount the engine so as that the crank is on the axle line with a propperly setup suspension so as to neutalize it's effect on leaning.
Lastly you've got COG and other rotating parts (cams, tranny assemblies, gears, etc).
Steering geometry and all that has nothing to do with how a bike leans. My rat bike with 2.5"/3.5" wheels, lightened rotors and race rubber will flop back and forth faster than you can blink...but, with a 80" wheelbase, it doesn't turn for shaZam!.
If you want to see something crazy-flickable...find a bandit 400 with lightweight wheels, aluminum sprockets and lightened rotors. My TL will lightweight wheels and rotors is almost as flickable.
4d
What Honda did to eliminate torque effects on the Gold Wing: they have the alternator rotor rotate against the crankshaft with twice the RPM at half(?) the weight. That compensates crankshaft inertia issues.
Made BMW and Guzzi look pretty lame when they came out with it.
[4
Quote from: AlphaFire X5 on April 11, 2006, 10:37:54 AM
It's a combination of things. Light weight. Upright bars that you can put a lot of torque on, and skinny ass tires.
light weight? :o :dunno_white: :cookoo: :icon_rolleyes:
Quote from: JetSwing on April 12, 2006, 08:01:08 AM
Quote from: AlphaFire X5 on April 11, 2006, 10:37:54 AM
It's a combination of things. Light weight. Upright bars that you can put a lot of torque on, and skinny ass tires.
light weight? :o :dunno_white: :cookoo: :icon_rolleyes:
Well, compared to a cruiser or a big Bandit or something. It's all relative.
Quote from: Wrecent_Wryder on April 12, 2006, 04:32:03 AM
Quote from: scratch on April 11, 2006, 04:12:57 PM
Quote
How do you get a flat 6 into a bike with the crank rotating parallel to the frame?
Parallel with the frame, lengthwise.
Ok- so the Wing crank is rotating on the same plane as the Guzzi or BMW boxers, then.
Yes.
I'm so lost. So are the cranks on BMW's, Guzzi's, and Wing's set up perpendicular to the frame? And ours is parallel to the frame? Am I in the neighborhood here? Hello? I'm Dave C?
The engines in Moto Guzzis, Beamers, some Triumphs, Goldwings, Runes and all the like are longitudinally mounted...that means that the ends of the crank are pointing at the wheels. GSXR's, CBR's, ZXR's, YZFR's and the like all have transversely mounted engines (self explanatory).
The altinator thing on the Goldwing isn't that spectacular. Most of the longitudinal bikes are cardan-drive and the majoraty of the transmission assembly and shaft all rotate opposite the motor.
Quote from: makenzie71 on April 12, 2006, 10:13:36 AM
The engines in Moto Guzzis, Beamers, some Triumphs, Goldwings, Runes and all the like are longitudinally mounted...that means that the ends of the crank are pointing at the wheels. GSXR's, CBR's, ZXR's, YZFR's and the like all have transversely mounted engines (self explanatory).
Huh? I'm lost. So the engines on a CBR and whatnot are set up so if you look down from the seat, the frame and crank (if it were visible) would create a cross or a t? But they're an inline-4, and...
Wait, so the cylinders are in line with each other, not the frame. Ok, and so that explains why the exhaust valves are oriented like that, with the 4 at the front of the bike...
Did I just talk this out? Or am I was off again? I'm self-taught when it comes to engines, AKA I don't know shaZam!.
Yes! An inline 4 is four cylinders across in a transverse mounted engine (that is transverse mounted in relation to the frame and/or line of travel).
Quote from: scratch on April 12, 2006, 10:48:14 AM
Yes! An inline 4 is four cylinders across in a transverse mounted engine (that is transverse mounted in relation to the frame and/or line of travel).
An inline engine is just that...piston configuration bears no reference on how it's mounted. It can be mounted longitudinally or transversely.
The Rocket III, for example:
(http://www.corbin.com/triumph/r3fair2.jpg)
The reality of the heavy ass crank Inertia can be easily felt ... take a fat ass I 4 like my eli 1000 ... and running 60 or whatever speed ... try turning it ... then attempt the same curve at the same linear speed with the clutch in and motor idling ... or even shut off ... OK shut it and you may be walking home pushing that 800 lb bike ... but it will turn or go through a curve a lot better with the clutch in ... so much so ... you'll feel like some sheite is busted on it ...
That is almost the single largest factor why V twins or parallel twins turn it better than I 4's ... my virago vs my maxim ... another huge difference inspite of being close to same weight, same geometry and same running gear and suspension ...
Cool.
Srinath.
Quote from: AlphaFire X5 on April 12, 2006, 08:11:45 AM
Quote from: JetSwing on April 12, 2006, 08:01:08 AM
Quote from: AlphaFire X5 on April 11, 2006, 10:37:54 AM
It's a combination of things. Light weight. Upright bars that you can put a lot of torque on, and skinny ass tires.
light weight? :o :dunno_white: :cookoo: :icon_rolleyes:
Well, compared to a cruiser or a big Bandit or something. It's all relative.
hehe, relative... i'm with Pablo :thumb: