GS1000 Yoshimura Piston Rings

[Brew_Up]

Ive got a Yoshimura big bore kit to fit my GS1000 but its missing one piston ring, the piston measures 73mm dia, does anyone know where I can buy a replacement set for this. Ive tried one company but they say that they cant get anything to fit and that the only big bore option is a Wiseco 73.5 kit.

Many Thanks,
Dean

[steve murdoch]

Welcome to the site.

An old thread that shows they are difficult to find.

http://www.thegsresources.com/_forum/archive/index.php/t-134498.html

Don't now if it is of any value but i remember helping a buddy with a mid '80s xr250. It had a 73mm piston.

[Nessism]

The Wiseco makes 73mm pistons for the GS1000. By chance do you have the ring thickness measurements, or at least the width of the piston groove. You best bet may be to try to match something up. 73mm pistons are reasonably common.

[Fjbj40]

I tried for quite awhile to find rings for these Pistons. I checked many manufacturers specs and could not find any.

The final conclusion was to have the Pistons reground to accept newer style rings as the original rings are quite narrow. Not sure if Yosh had a street and a track set of these Pistons but mine were very narrow grooves.

I contacted a fellow at one of the piston manufacturers and it was $40 per piston to recut. Add shipping there and back and I was not far off a newer modern set of Pistons.

[Brew_Up]

Thanks for the quick replies.

I was given the Yoshi kit with a rebored cylinder, but it has got one ring missing. As the rings also need changing on the standard pistons fitted to the bike I was hoping to use the big bore kit instead. If its going to be that much of a pain to sort rings for the yoshi kit I'll just stick with the standard setup. The bike is a rolling restoration so I don't want to blow all my budget on one thing. It may need valve guides and a valve replacing too.

[Fjbj40]

RapidRay told me he has a source for Yosh ring "replacements".

That's good news, I wish he would share that info in the "for sale" section!