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Main Area => General GS500 Discussion => Topic started by: johncam4 on June 22, 2004, 06:10:30 PM

Title: There is hope for more hp
Post by: johncam4 on June 22, 2004, 06:10:30 PM
well i think.... i read this some where....... " I have been told that for every pound of weight you knock of the bike that rotates.......magneto, stater, crank, wheels, chain, brake rotors is eqaul to like 1.5 hp effective."
what do yall think
Title: There is hope for more hp
Post by: gitarman on June 22, 2004, 07:04:17 PM
yes thats true it follows some basic physic's principles...so whatcha gonna do about it? :mrgreen: carbon fiber rims? lightweight flywheel? a lot of those parts can't be lightened much more without sacrificing durability and safety.

Let us know how ur search turns out we all are looking for some more HP....especially if its cheap haha
Title: There is hope for more hp
Post by: Muldoon on June 22, 2004, 07:14:32 PM
Reminds if a time long long ago when I used to navigate in various rally cars. I was in a friends workshop where he was working on his new Lancer rally car. Aluminium bolts, titanium foot rests, all the alloy and carbon you could want to save weight. Dude was an absolute bear about saving weight. Which was funny as his navigator weighed over 200kilograms! I made the suggestion that the best way to get weight outta the car was to lose tubby and employ someone of slightly less robust nature. If looks could kill! :thumb:
Title: There is hope for more hp
Post by: Reknelb on June 22, 2004, 07:14:51 PM
I took the counter balnce out, the stator the charging rotor, starter and all related gears. Came out to something like 19lbs off the weight of the motor. Most importantly the rotating mass of a 6lb balancer, charging rotor and starter gear :thumb:
I'll let you know what it puts out on the dyno when I get my throttle cable.
Title: There is hope for more hp
Post by: Blueknyt on June 22, 2004, 08:32:03 PM
Quotetook the counter balnce out, the stator the charging rotor

you ballenced the crank?  where did you do it and how much, and let the rest of us know how streetable it is, how the vibration compares to what.
Title: Re: There is hope for more hp
Post by: Lee from Toronto on June 22, 2004, 09:24:41 PM
Quote from: johncam4for every pound of weight you knock of the bike that rotates.......magneto, stater, crank, wheels, chain, brake rotors is eqaul to like 1.5 hp effective."
what do yall think

I'm thinking Atkins.

Oh wait, that's only if YOU rotate on the bike, isn't it? :)
Title: There is hope for more hp
Post by: Bob Broussard on June 22, 2004, 09:26:47 PM
I don't think you'll see the HP gain on the dyno. But you'll feel it on the track.
:dunno:  :dunno:
Title: There is hope for more hp
Post by: glenn9171 on June 22, 2004, 09:39:36 PM
A lighter flywheel will get you even less torque...for a very slight gain on top-end.  Not exactly what the GS needs.
Title: There is hope for more hp
Post by: werase643 on June 22, 2004, 11:31:55 PM
i always heard that every 7 # of mass removed was like adding 1 HP

that is why there are a bunch of FAT GUYS on BUSA's....i can't lose weight...i need more power... :roll:
Title: There is hope for more hp
Post by: MarkusN on June 22, 2004, 11:40:54 PM
It was rotating mass,. which counts double and treble. And you won't see it on the dyno. Taking mass away will make your Engine more responsive, but it won't improve the conversion of heat energy into power on the shaft.
Title: There is hope for more hp
Post by: Ed89 on June 23, 2004, 05:03:14 AM
It depends on the mass (weight) distribution of the rotating mass, i.e., the moment of inertia (angular inertia).  For example, given a ring and a disk, both of equal weight and equal diameter, (the disk could be flatter if you want to use the same material, say, iron), the ring has a higher moment of inertia than the solid disk.  So the ring will need more torque to accelerate as fast.

Bunching up the weight close to the center (less inertia) is better than distributing the weight far from the center (more inertia).

Cheers,
Ed.
Title: There is hope for more hp
Post by: JLKasper on June 23, 2004, 05:22:55 AM
The most viable place to look on the bike to lose rotating mass is the wheel assembly.  Since the rims are hollow (and lightweight rims are $$$)and the rotors are already swiss cheesed,  the most logical place to look are the tires.  It only makes sense that the smallest sizes (stock) should be used to get the job done.  Besides that, there are enough variations in weight from one manufacturer's tire to another (1-2 lbs), and also perhaps in radial vs. bias that this might be the cheapest place to improve performance.  :cheers:
Title: There is hope for more hp
Post by: MarkusN on June 23, 2004, 05:31:27 AM
Quote from: JLKasperThe most viable place to look on the bike to lose rotating mass is the wheel assembly.
Not too sure about that. As the wheels rotate relatively slowly loosing weight there will not count as much as on the fast rotating bits of the Engine.
Title: There is hope for more hp
Post by: snapper on June 23, 2004, 05:44:43 AM
Well if this is the case I would guess I have more HP than most.    :P
Weighing in anywhere from 98 to 102 gives me that edge.  LOL
:mrgreen:
Title: There is hope for more hp
Post by: Bob Broussard on June 23, 2004, 10:12:34 PM
Lightening any rotating mass (wheels, flywheel, etc.) will improve performance. The bike will accelerate quicker and handle better.

All rotating parts act as gyros (including motor internals)
This effects how the bike handles through corners.
Lighter wheels, for example, will hold a tighter line through corners with less tendency to steer wide.
I personally prefer my motor with the counterbalancer, but no flywheel.
The bike carries more momentum through corners. It still has plenty of response out of corners.

If you remove the flywheel, you need to plug the oil hole for the starter gear on the crank. I just spot weld it, since I'll never use the flywheel.
Then I put the bolt back in the tip of the crank. That way you won't lose any oil pressure to the main bearings on that side of the motor.

If you remove the counterbalancer you need to plug the oil holes for the bearings in the case. I just used some bolts. Cut off the head and cut a slot with a hacksaw. Then they can be removed if you want to put the balancer shaft back in.