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Getting your chassis to handle your blazingly fast Suzuki powerplant.

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Admin
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Post by Admin »

I would've picked one up if I hadn't just fitted one one mine.

Nice welds! I usually don't see them looking that right unless my brother whose been welding aluminum for 14 years did them.
Admin
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Post by Admin »

Sweet.If all things go well I'll see if I can Cough up enough for one. :grin: I can't make any Promises right now though. :?
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Post by Admin »

Wow, thats a great looking job on the swingarm!
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Post by Admin »

twostrokin wrote:OK, then 7.4 ounces. I started looking into it because my forks sound like they are sucking air with the volume the owners manual states. Thanks!
Bump
This comes too late for you, twostrokin', but I thought I'd give an update. You did say your bike is a GT500, right? My Clymers doesn't list fork refill amounts, not that I can find. But if yours says 7.4, it's incorrect. So is the link dave provided. The website chart you found by yourself is correct. If your owners manual says 4.5, I think I'd burn it to prevent me from using it again, LOL.

The Suzuki GT500 factory supplement states:
Oil Capacity: Each leg needs 266cc or 9.0 US ounces (9.4 Imp) of oil, in contrast to 220cc or 7.4 US ounces (7.7 Imp) needed by the fork leg in T500.

If you'd rather use oil level, I installed exactly 266cc into completely dry, freshly assembled forks. Then pumped the forks to distribute the oil and measured the oil level. It's 150mm from the top of the tube with tube compressed fully and spring not installed.

Geezer
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Post by Admin »

Hmmm, maybe that's why my GT500 forks didn't have any damping! I don't remember how much oil I had in them, but it wasn't 9 oz! I put GT750 forks on it, and the improvement was amazing.


Lane
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Crudy T500 swingarm

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I recently got my swingarm blasted and painted. I left the bushings in as I wasn't going to replace them. The genuis painter guy taped off the ends, but due to the quality of the rest of his work, I second guessed the inside of the swingarm. Sure enough I could feel grit in the grease. I can see that Im going to have to take out the bushings in order to clean this peice properly. In the past I've had bushings crack when Ive tried to remove them. These are painted so I can not tell if they are plastic or not. What would be a good way to take theses bushings out without destroying them?
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Post by Admin »

You probably can't get them out without destroying them, but they probably need to be replaced anyway. It really tightens up the rear end when the bushings are not worn.
Unfortunatley, they should have been removed and new ones installed before painting as it will be dificult to remove them without damaging the paint. It may be possible, but you are going to have to be really careful. Installing the new ones can probably be done easily enough without damaging the paint if you use a bearing press.

Wayne
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Aluminum swingarm for at GT380?

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I've been reading the threads on converting the 500 to an aluminum swing arm and saw the thread with the custom made swing arm.

I'd love to change mine, but the cost for the custom made job is a bit too rich for me right now. Maybe later on.

Does anybody know of a direct bolt on replacement, even if it lengthens the bike by a few inches?
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Post by Admin »

I dont' know any bolt on replacement, but.... "few inches"?... they seems to me way too much. Those elongation would be measured in inch fractions.
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Post by Admin »

What you need to do is to take a few critical measurements of the existing arm and work within those figures.
Since the 500 is quite a narrow bike you will have to look at arms from some pretty small sized modern bikes to stay within the dimensions you need.
Most critical is the pivot width section and the ability to reduce the new arms width if need be, its no sense trying to cut into the spars if they are too wide at the pivot section.
Spar length is also in consideration too since the 500s arm was pretty long already. So you definately dont want to make it any longer, as this will make the bike look stupid, handle weirdly, and upset the present rr fenders alignment to the tyre.
Also shock mounts are no longer the same, later bikes went to lower shock clamp mounts over eyes and you may have to adapt some mounts to the arm.
Theres also the chance your find will more than likely be a mono shock unit and therefore have no location for shocks and some will have to be fabricated and welded on.
I'd look around the wreckers yards near you armed with your present bikes swingarm dimensions first to get an idea of whats around that might be able to work.
Conversion work and final price will be set by the type you settle on, so you need to choose VERY carefully for making this project work and look correct.
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Post by Admin »

jbswear,

If you are lucky enough to have a decent cycle salvage yard nearby, measure:

1. The width of your stock swing arm at the pivot point

2. The length of your swing-arm from pivot center to the front edge of the axle slot.

3. The distance from the pivot center to the center of the shock eye.

4. Inner and outer swing-arm width at the axle.

Then start looking at dirt bike swing-arms. There were several years in the late '70's/early '80's where the swing-arms were aluminum and still dual shock. I can tell you an FZR400 ally swinger fits a GT550 frame easily but I'm not sure it's narrow enough for a 380 (plus the FZR400 swingers are hard to find and you have to weld on shock mounts).....

Hope this helps!

Jim
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rr shock disassembly

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Here it is in three simple photos.In this case a hydraulic press was used to compress the spring to allow access to the top of the shock eye.


Image
Image
Image
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Post by Admin »

The correct fork oil for the T500 was listed as a single weight 20 or 30W i believe.
ATF will be way too thin for the old Titan forks, so thats one big problem you have already.
There not much you can do in terms of getting improved performance parts for these old external spring forks since they are pretty much a simple pathetic design anyhow.
Flush and refill with the best quality oil and amount needed of the specified weight and then work from there.
Basically you can play around with oil viscosity to affect rebound damping somewhat but you will need different spring rates to really change fork action.
Remember theres no compression or rebound damping external adjustments so you have to use different oil and springs to achieve this effect.
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front end

Post by Admin »

If it really bugs ya, You could swap out the front end to a slightly more modern one but one that still keeps the Look of your t500. Something that has variable rate springs avalable?? Dofin
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bushing

Post by Admin »

I was really ticked when I changed out my bushings. Did the brass one and when I tied to put my pivot bolt in the Darn thing wouldnt go in. The Bushing hole wasnt largeenough!! I had to find a proper sized reamer and ream the thing out. Pain in the but. so worried I would get it to big and there ya go! Good luck!!
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