Cylinder Identification

[Deleted User 287]

Matt says he has a set of Nikasil R65 cylinders, and I could use them. I just want to make sure they are the same size as the ones on my bike, so the pistons will fit. I understand there are 3 different non-oversize cylinder/piston sets as they came from the factory.

Can you help me understand the numbers & letters on the castings?
TIA!
Click on any of the pictures to enlarge them.

This is the right cylinder - a zero and six to the left of the 'A' and a one and nine to the right:


This is the left:


This obviously means it is for a R65:


This is the left cylinder, it says 82ZN4W2. The right side says 82ZN4W1


G ·



http://www.pbase.com/tomfarr/nikasil_engine_interior

[Deleted User 62]

OK Rob, the "A", "B" and "C" are the three sizes available from the factory. For R65: A = 81.995 - 82.005mm bore which is the smallest of the three. According to my Haynes, if those cylinders are within spec (haven't been bored), you'll need pistons that are 81.955 - 81.965mm.

[Deleted User 287]

Thanks Tim. Yeah - the A, B, C sunk in while I was writing to Matt.

I doubt they have been bored since they are Nikasil.

As long as Matt's are "A"s, I should be good.
Then I'll have to find the money for ring$.

[vanzen]

OK Rob, the "A", "B" and "C" are the three sizes available from the factory. For R65: A = 81.995 - 82.005mm bore which is the smallest of the three. According to my Haynes, if those cylinders are within spec (haven't been bored), you'll need pistons that are 81.955 - 81.965mm.

Nik cylinders typically are not bored.

Simply match the letter stamped onto your old cylinders, in this case, "A",
and the replacements, if also marked "A" – should spec to your pistons.