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AJS/M SINGLE PISTONS

A note on GPM pistons: the size indicated is the bore size of the barrel. GPM pistons are slightly undersize to this bore. If you race the bike or put it to heavy use the bore may be a touch bigger. Also use SAE50 oil.
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350CC PISTON 1949 UP
ZGPM6916
!
GPM pistons are slightly undersize to the nominal bore.

CS 500 PISTON
ZGPM862A
!

All in weight 717gr. for the STD size, so you'll have to grind some flesh away.

More details

PISTON 350CC 1949 UP
ZM350
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Make "GNP". Old stock.  Complete with rings and circlips

PISTON EARLY 350
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New old stock. Various makes.
These will ONLY fit 1940-1948 models. (SMALL CYLINDER HEAD)
Only a few available

PISTON RINGS 350CC
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STD size is 69mm

PISTON RINGS 500CC SINGLE
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Please state size