Malossi AV10 h2o cylinder kit tolerances

I've been trying to get info on the recommended tolerances for the Malossi Motobecane h2o kit, and even emailing the Malossi customer support yielded nothing. Anybody got numbers for piston clearance, ring gap (I know the standard 6-8 thousandths, just wanted to confirm), wrist pin clearance, etc.

Re: Malossi AV10 h2o cylinder kit tolerances

typically buying a kit you are counting on the manufacturer to have the piston to bore clearance correct, there are going to be a lot of factors going into that decision and its not just a single number, the piston is machined with taper so it can expand more near the top.

stock aluminum /nikasil cylinders run a bore clearance of about .0018", stock cast iron bore are a little bit more, .0020" is a safe margin

but, that is assuming air cooled, wich is going to run hotter cylinder temps therefore more thermal expansion, a H20 cylinder is going to expand less meaning there needs to be more clearance.

Point being, even if you bust out your handy micrometer and snap gauge and measure it in a bunch of different places, you'll get a bunch of different measurements so you're really counting on malossi to have their shit together out of the box or you're pretty much screwed.

Re: Malossi AV10 h2o cylinder kit tolerances

Yea, I mean I always check ring gap and only on the really cheap "house-brand" kits has it been an issue. I've got a little gauge I think it's .006. I've had some that were close and thought, meh it-s close, and sure-nuf it was fine, the "not fine" ones have straight up butted against each other. there's definitely room for proper tolerances but if the malossi factory tolerances are the weakest part of your setup, then you're a helluva a better builder than I'll ever be

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