G3LS Cylinder standard bore limit wear

Information relating to the Matchless G3 or AJS Model 16 350cc Heavyweight
JEAN-NOEL
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Re: G3LS Cylinder standard bore limit wear

Post by JEAN-NOEL »

Hi Kees,
what brand is your piston ? I have had a problem with JP on a twin. The right one was OK, but the left pot spat a lot of oïl. The ring were fitted wrong way : they were taper, and the ridge must be at bottom side. Correctly fitted, no more problem.
Regarding the clearance, new, circa 5 thou - 12/100° mm.
i think the best way to do is an accurate check by a good workshop. If your barrel is badly worn, its make sense to resleeve it, as you have yet a new piston. If it is not, a light honing will be enough to have the rings bedded in.
Kind regards.
56G80S
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Location: N YORKS UK

Re: G3LS Cylinder standard bore limit wear

Post by 56G80S »

Bitza - I reckon that's what I remember Frank Reynolds doing all those years ago when I was using his shop to fix the matchless in the mid 1970's.

Kees - I had my barrel re-sleeved to standard. Depends on your expected mileage.

Johnny B
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jackstringer
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Re: G3LS Cylinder standard bore limit wear

Post by jackstringer »

I was just looking through the Matchless G3 manual for the 1960s bikes (http://archives.jampot.dk/book/Owners_m ... models.pdf) and I spotted on page 38 under Oversized Parts & Reboring Cylinder Barrel,
When the wear at the top of the barrel reaches 0.008" the barrel should be bored out 0.020" oversize and a new oversize piston and rings fitted.
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