AJS & Matchless Owners Club

The info given above relates to the use of a Twin piston in a Lightweight 350 and is incorrect. It is actually a 1959 only 650 Twin piston that fits into the Lightweight 350. If you fit a 600 piston the compression is very low due to the gudgeon pin being nearer the crown.


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Thank you all who replied. I did try a 600 piston , disregarding it due to the gudgeon height. I do not have a '59 piston to try, but it does open up an opportunity. I also understand Triumph 650 pistons can be used in a longstroke 350, but this has been overbored so again, discarded. Excuse the ignorance, but who is John Harding ?
Marty

John Harding advertises in Old Bike Mart, "Pistons..." He also supplies rings, UK phone number 01989 750731. Was very helpful a couple of years ago when I was looking for rings for my G9.

Just a note as to the outcome of my experiment, I have used a late 650 +40 piston which I will slightly reshape the crown to suit the 350 head and fit a 3/4" gudgeon bush. I did this because I had one and the gudgeon heights were similar
Marty