Where do I go, where do I go, where do I go now?

spookefoote1956 · Post by **spookefoote1956** » Fri Aug 05, 2022 1:15 pm

Did you fit a +20 piston though Dave?

dave16mct · Post by **dave16mct** » Fri Aug 05, 2022 1:37 pm

Yes it was a 1954 G3LS. +20 piston and at that time(about 1980) we had a member called Eric Hatton who bought a massive stock of piston rings. He spent a long time measuring them (he had a special gauge for it) and sorting them into sets which he sold to members very cheaply. I went to see him and he only had the +30 rings. He insisted they would be would be fine if I checked the gaps were OK. I think I filed them to sizeI never had a problem with it.
Dave.

Greybeard · Post by **Greybeard** » Fri Aug 05, 2022 2:24 pm

The ones I had were the next size up by 10 thou. With the rings in the bore and held up to the light you could see a crescent where the rings didnt touch. I suppose if you were prepared to put up with the 2-stroke type smoke trail they may have bedded in - eventually. Logic says if you compress an oversize ring to a smaller size itll not have the same even curvature. that it was made to have. Something you might get away with if the bore is very worn.

Steve

dave16mct · Post by **dave16mct** » Fri Aug 05, 2022 7:05 pm

Look I'm not advising anyone to do this. I'm just saying I did it on a 350 which would've been about 70mm bore and it was good. The bore wasn't worn and the rings were 10thou bigger.There was no smoke and it had very good compression. I know the rings were +30 because he had the special gauge to measure them. How do you know that the rings you fitted were'nt much bigger and in the wrong box. I can't find who was advising using bigger oversize but G5wqian posted that he had used +60 rings on +40 pistons on a 600 twin (72mm -ish bore) and with a good result. I don't want to get get into an argument so this is my last post on this.
Love and kisses, Dave.

spookefoote1956 · Post by **spookefoote1956** » Fri Aug 05, 2022 7:22 pm

No arguing fellas

Greybeard · Post by **Greybeard** » Fri Aug 05, 2022 8:26 pm

I didnt realise it was an argument - just offering an alternative experience

Im off! Good luck with however you decide to sort it

Steve

spookefoote1956 · Post by **spookefoote1956** » Fri Aug 05, 2022 8:35 pm

All help and advice is always much appreciated.

spookefoote1956 · Post by **spookefoote1956** » Tue Aug 09, 2022 1:57 pm

Huge thanks to ajscomboman. I've managed to get some rings from Kit at Cox and Turner. Hussah!

Trefor · Post by **Trefor** » Thu Aug 11, 2022 12:04 pm

I've had a JP piston running in a G80 for 12 years with out any problems. The chap who did the re-boring told me he gave it a generous clearance.

spookefoote1956 · Post by **spookefoote1956** » Mon Aug 15, 2022 10:43 am

Rebore, wire wound piston, adjust the clutch, Hussah!!
https://drive.google.com/file/d/1bgdjay ... sp=sharing

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Where do I go, where do I go, where do I go now?

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