GT500 Race Prep

Getting your chassis to handle your blazingly fast Suzuki powerplant.

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tyf324
Still in the Driveway
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Joined: Sun Mar 10, 2013 9:46 pm
Country: USA
Suzuki 2-Strokes: 1976 GT 500

GT500 Race Prep

Post by tyf324 »

I was wondering what the best option would be for a shorter, more stout swingarm for the GT500. The stock swingarm is too long. I purchased a GT250 swingarm and it is just a bit too short as I ran my expansion chambers under the cradle of the frame. I really don't want to shorten the stock swingarm, nor lengthen the Gt250 swingarm.
Would a GT550 swingarm work with minimal alterations?
Thanks.
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smokin_blue
On the main road
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Joined: Fri Nov 01, 2013 8:30 pm
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Suzuki 2-Strokes: www.street-unique.com
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Re: GT500 Race Prep

Post by smokin_blue »

You said the GT250 SA was too short. How long is it from the center of the pivot tube to the center of the axle slot? (I no longer have my 250 to go reference)
'07 Suzuki SV650
'90 GSX-R1100 streetfighter
LS650 powered custom framed café
'72 T500 with a Lyster frame
'69 T500-parts/project?
'83 GR650-project

Past bikes
'06 Triumph Sprint ST
'86 GSX-R750
'74 GT250/T350 custom
'79 GS750
'74 TS250
'81 TS100
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Alan H
Moto GP
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Suzuki 2-Strokes: 4 x GT550s - J, M, A, B.
Location: The Republic of South Yorkshire

Re: GT500 Race Prep

Post by Alan H »

IIRC the early T500 swinger was shorter and Suzuki lengthened it to make the bike handle better.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
diamondj
Road race school
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Re: GT500 Race Prep

Post by diamondj »

GT550 would be too wide for a T500. Often people have used the T350 swing-arm but it would be the same length as your 250 arm. An RD350 swing-arm should be somewhere in the middle and narrow enough to fit without a lot of work.
Zunspec4
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Suzuki 2-Strokes: T500R, SV1000S, TS125, Seeley T500
Location: Trowbridge UK

Re: GT500 Race Prep

Post by Zunspec4 »

Hi tyf,

There are several T500 race bikes that compete in the CRMC 500 Air cooled class that use the std. frame and swinging arm. Effort seems to have gone into improving the suspension with decent rear shocks and uprated front forks (TZ forks are a favourite). Also a twin disc conversion using typically AP Lockheed or Grimica twin piston calipers (I think a single disc is more than enough personally).

If you are set on using a shorter swinging arm it might be worth considering getting one custom made. Dresda used to make a box section arm to fit the T500/GT500 but I guess they would be like Hens Teeth to find today. In the UK I know of several outfits that could fabricate a new arm if given the task, there must be similar guys in the USA race scene that could do the same for you.

Cheers Geoff
Suspensionking
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Suzuki 2-Strokes: T500 Suzuki, AJR Bultaco, Honda NS475

Re: GT500 Race Prep

Post by Suspensionking »

Hi Tyf,

I would agree with Geoff the best option would be to have a new swing arm made. I race a T500 but its in a TR Yam frame. I actually wanted to go the other way and lengthen mine. In the end the person who prepares my bike bought some Chrome moly box section from the states and fabricated one. I work for a USA based suspension company and ended up custom building some shocks to work with the swing arm. I had to increase the length of to make the bike turn.

Eamonn
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