T500 cylinder - Early vs. Late

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motomailer
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Suzuki 2-Strokes: GT500, T250

T500 cylinder - Early vs. Late

Post by motomailer »

Dear all

recently I've got a box with some T500 and other stuff. There are also some T500 cylinder and two set of carburators (32mm and 34mm).
How are I'm able to distingush between the very early and the late T500 cylinders? I don't have any engine case were I can see the engine number nor there is any number on th cylinder itself.

I'm aware that there was already the same the topic
viewtopic.php?p=87614" onclick="window.open(this.href);return false;

There some of you were mainly talking about the intake and that "aluminum of the cylinder is split along with the steel liner".
According the parts list there were also different pistons used and I've seen a comment in the following US Suzuki Technical Bulletin that they are not interchangeable.

https://www.oldjapanesebikes.com/mraxl_ ... s/page-A54" onclick="window.open(this.href);return false;

It's just because of this intake port liner? Mechanical strength issue? Some other differences?

When I have a look at my cylinders. All have this steel liners only. Intake port diameter is around 34 to 35mm. I'm able to use the early pistons only?

Thanks you very much for your inputs.

Best regards
Roland
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Re: T500 cylinder - Early vs. Late

Post by old racer »

https://www.ebay.co.uk/itm/Suzuki-T500- ... Sw5dNWtkx3" onclick="window.open(this.href);return false;

This is what the early pistons look like.
motomailer
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Re: T500 cylinder - Early vs. Late

Post by motomailer »

Hi Old Racer

I know how both piston types look like. I‘m more intersted in the differences of the cylinders and may the pistons are not interchangable.

Regards Roland
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ConnerVT
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Re: T500 cylinder - Early vs. Late

Post by ConnerVT »

All of the cylinders (with the steel liner) are the same, as far as pistons go.

There were several generations of pistons:

First pistons had large, windowed piston skirts.
Later pistons have open skirts.
With the introduction of the GT750, the skirts were again slightly modified. As Suzuki likes to manufacture as few part numbers as possible, these pistons superceeded those before them.

Skip the old, windowed skirts. They were a good idea, but practice found the skirts to be weak, and would occasionally break. Any of the other pistons will work, for a road bike with normal usage.
motomailer
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Suzuki 2-Strokes: GT500, T250

Re: T500 cylinder - Early vs. Late

Post by motomailer »

Hi ConnerVT

thanks for your input :clap:

Regards
Roland
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Re: T500 cylinder - Early vs. Late

Post by Vintageman »

Yes later OEM pistons work older cylinder and best. If you want run at high rpms or modifying / porting consider forged like Wossner.

The older cylinder has lower intake port windows for longer port open time. Maybe 2.5mm if I recall The exhaust port is the same but seam to vary +/- 1mm ... at least from people who have checked so I would say the same just mfg tolerance.

I put the older cylinder on later bike and worked fine and definitely more top end. The later stock would just run out breadth too early. I stayed with the later carb manifold, carbs and air box and jetting. I have chambers. I do have all the intake early stuff as well, but the cylinder alone did the trick and my bike looks OEM. It is my opinion the cylinder was mainly why the later bike lost top end. Still peak torque relatively low RPM on both models stock and I think the longer intake from later model is tuned better for a strong midrange as well. I have a very flat feeling torque curve and bike is quite able to hit redline now, where before it was a struggle at best. And both were fresh bore and piston too

Well if you have choice which cylinder run the early one is what I would pick every time and my current thinking on pistons: Latest stock or forged if hopping it up,

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motomailer
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Re: T500 cylinder - Early vs. Late

Post by motomailer »

Hi Vintageman

thanks for your additional input. I'lll measure the intake port and see if there is any difference. Do you have any reference values at all?

BR, Roland
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Re: T500 cylinder - Early vs. Late

Post by Suspensionking »

Hello Roland,

I race a T500 in the Spanish classic championship and ran standard pistons (later ones) the first season. when the engine was opened the engine there was some cracking, I rev the engine to 9000rpm. Then changed to wiseco, and they till now have been working well.

If you are doing Hill climbs in Switzerland you may want to consider them.

Eamonn
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Re: T500 cylinder - Early vs. Late

Post by Vintageman »

Wiseco good too. I am a champion for Wossner for they have gone out on a limb to make vintage pistons. Wiseco will too if you buy min quantity. Wossner publishes one clearance where I think wiseco still gives range depending how you use. Wossner coated for T500 and that stuff lasts. Wiseco not always and think not for Gt750/T500?. Both strong

motomailer

It was post on here maybe 2-3 years back I think that I started? I tried to search and wouldn't work. I'll try later. You can try too I think I had Photobucket links but photbucket seams to have kicked the bucket. I think we took some measurements


I was just lower by 2.5mm I think?. The two windows measured together across were not as wide as the later. The center casting was thinner with since no aluminum out crop like the later and they made the divider a little wider to accomdate.

I think the early T500 dimension, vertical wise, are the same as the later GT750 porting specs. There are docs on the web that show both and I think the T500 I got from a early factory porting spec which showed stock ....I think you can now find on oldjappanesebikes.com or something like that.

The T500 is fun and just a little bit of tune like the early setup makes a difference. Easy to go too far... just stock up on cylinders. There are period articles that compare both and one vendor explained how disappointed they were with the later tuning. Some guessed it was to make the GT550 appear faster ...who knows truth.

I was at a stop light and a SAAB 2.0 Turbo got a jump and me and I could not quite pass it before lane went 2 into 1. I would like to try that again with this older top end setup... Don't recall if I had chambers at that time or not. Jemcos don't seam to add top end and tuned to complement current power band shape. which can cause ping if not jetted a little rich. Dang domed head design. Shorter pipes with overall tuned length 500 RPM higher may be the key to help over rev and increase RPM. Now start considering forged pistons.

All chambers like Jemco, Titan etc. and current slip on set on eBay now (Bassanni he thinks) seam to be same shape/design? I would like to ask Jemco or Titan to make a shorter center piece a few inches. Don't need midrange boost a little over rev pull would be sweet.

Still it is very mild bike and can lug along or cruse at highway speeds. great street bike that may do a 14-15 sec 1/4 mile

As always way too much info and opinions

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77 Yamaha RD400 (Daytona Cyls),
motomailer
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Re: T500 cylinder - Early vs. Late

Post by motomailer »

Dear Eamonn and Vintageman

Thank you very much for your feedback.

In a first step I'm interested in the type (early or late) of cylinder only. I've got some of them without any pistons nor engine case. Therfore I've no clue about the year. I just read the statement of Suzuki not to mix up old cylinder and new pistons or vice versa.

Now I've found the topic you were talking about. In principle it's the same as I'm interested in.

viewtopic.php?f=2&t=7198&hilit=Port+measurement" onclick="window.open(this.href);return false;

This helps me a lot. I'll measure them too.

Regards Roland
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