Cutting Swingarm

Getting your blazingly fast Suzuki powerplant to perform even better!

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MazerRackham
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Cutting Swingarm

Post by MazerRackham »

What are your guys thoughts on shortening the swing-arm length? Given my short time on the forum this topic may have been beaten to death already, so please forgive me. Given the benefit of using modern shocks is this modification really "felt?"
titan performance
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Re: Cutting Swingarm

Post by titan performance »

I think some of the 500 race boys cobble in the 250 swing arm, which shortens wheel base by about an inch.
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two-stroke-brit
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Re: Cutting Swingarm

Post by two-stroke-brit »

i am all for swapping it out for a shorter s/arm from another model but would shy away from shortening the existing s/arm.
my .02 cents.
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diamondj
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Re: Cutting Swingarm

Post by diamondj »

This is for a T500? Are you racing the bike or is it a street machine? If you are racing, it might be worth it. If we're talking a street bike, it's probably more trouble than it's worth. You can sub in a GT250/T350 swing-arm but the tire will hit the fender mount on the frame so you'll have to change that, etc...

Personally for a street T500 I would get some good shocks - Progressive, Hagon, Ikon, or Works if you've got the cash for them - and put bronze bushings in the swing-arm. Then relace the front and rear hubs with 18" aluminum rims front and rear on stainless spokes. The smaller front rim will net you a better tire selection, speed up handling about as much as shortening the swing-arm, and reduce unsprung weight slightly as well.

There's my 2 cents on the matter....

Jim
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tgrogan
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Re: Cutting Swingarm

Post by tgrogan »

A better appraoch than fitting a 250/350 swing arm would be to narrow down a GT750 swing arm. You'ld get the added bonus of getting a much stronger s/a, as well as 2" shorter wheelbase. It would take some careful grinding/welding, but it sure looks possible. It's about 1" wider at most so shouldn't interfere with anything. Probably have to go with moving the top shock mounts forward in order to get to a useably shock length.
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tgrogan
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Re: Cutting Swingarm

Post by tgrogan »

I never shortened mine and never felt a particular need to. Replacing the front wheel with an 18" one seemed to provide adequate handling on all but the tightest turns on some pretty rinky dink tracks. Would never need it on the street, but moving the shock mounts forward to get a more reasonable length/travel does help.
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tgrogan
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Re: Cutting Swingarm

Post by tgrogan »

With a shortened swing arm it would be absolutely necessary! Read the posts and respond to what is obvious!
Terry

1968 T500, 1976 GT500, 1970 T250
2000 Ural Bavarian Classic Sidecar Rig
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MazerRackham
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Re: Cutting Swingarm

Post by MazerRackham »

lol

Take it easy on PEDRO man, we all know he means well. Thanks for the heads up brothers.
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Re: Cutting Swingarm

Post by ja-moo »

Getting past the "spat", and looking at numbers, there is a reason the smaller bikes 250-400 of any brand handles better. The lighter weight is one thing, but rake/trail and wheelbase is what makes a bike "handle". I looked up the specs and the t/gt500 had wheelbases from 57.2" to 57.7". That's in the range of modern 180 mph 1000's. Which they need for stability at 180 mph, but a 500 at just over half that top speed, makes for cumbersome handling. Then there is the trail. Which is 5.14" and 4.7" respectively, that is a LOT of trail, making for even more high effort steering.

I work on the Kawi triples, which have approximately the same numbers, and we all know how crap the stock handling is.

If you really want a sweet handling 500, then get the numbers closer to the smaller bikes. A 18" front helps, getting the trail at 100mm (4") and the wheelbase in the 54" range, and it will be a world of difference. Of course the standard mods of better shocks, tight swinger and steering head are necessary........ :up: And a steering damper for safety...... :P
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MazerRackham
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Re: Cutting Swingarm

Post by MazerRackham »

ja-moo wrote:Getting past the "spat", and looking at numbers, there is a reason the smaller bikes 250-400 of any brand handles better. The lighter weight is one thing, but rake/trail and wheelbase is what makes a bike "handle". I looked up the specs and the t/gt500 had wheelbases from 57.2" to 57.7". That's in the range of modern 180 mph 1000's. Which they need for stability at 180 mph, but a 500 at just over half that top speed, makes for cumbersome handling. Then there is the trail. Which is 5.14" and 4.7" respectively, that is a LOT of trail, making for even more high effort steering.

I work on the Kawi triples, which have approximately the same numbers, and we all know how crap the stock handling is.

If you really want a sweet handling 500, then get the numbers closer to the smaller bikes. A 18" front helps, getting the trail at 100mm (4") and the wheelbase in the 54" range, and it will be a world of difference. Of course the standard mods of better shocks, tight swinger and steering head are necessary........ :up: And a steering damper for safety...... :P
Thats whats up man. Thank you. I asked this in another thread, but it may be quicker to ask now. What are your thoughts on putting a Gixxer front end on this bike? I know they fit and allow me to put on modern disk brakes on for stopping power, but there must be cons.
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Re: Cutting Swingarm

Post by ja-moo »

MazerRackham wrote: Thats whats up man. Thank you. I asked this in another thread, but it may be quicker to ask now. What are your thoughts on putting a Gixxer front end on this bike? I know they fit and allow me to put on modern disk brakes on for stopping power, but there must be cons.
It's been done a lot on older bikes, but usually front and rear. I would think the better compliance would make the rear seem harsh.
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Zook-e
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Re: Cutting Swingarm

Post by Zook-e »

Just a little something I am playing with. 1968 T500 with GS500E front and rear end. I will be a monoshock.

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titan performance
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Re: Cutting Swingarm

Post by titan performance »

I've got nothing against "Franken" bikes.....at the end of the day it's each to his own, and if it pleases the owner, great !
I guess there is a combination of modern running gear, nailed to a T500 frame that may work, and give a good handling and stopping bike. We even considered, albeit very briefly, building one ourselves, but what we couldn't get to grips with was.....there are loads of modern middleweight bikes out there already that handle superbly, that have 100bhp motors in them, so why would you want one with half the power? We decided, that for the people who build that stuff, it's an excercise to show they can ! Again, not knocking it...whatever pleases you, but personally, I think sorting the handling on a bike that is still a T500 would be more satisfying.
Last edited by titan performance on Mon Sep 12, 2011 2:17 pm, edited 1 time in total.
Keeping old 2 strokes alive !
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