Rebore piston clearance ? I have a Ajs 500 twin M20 and want to rebore my standard barrels to +20.
I have a pair of BHE or (BHC) Split wire wound pistons . Like to know the clearance for threes.
Regards....Paul
rebore piston clearance
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- ajscomboman
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Re: rebore piston clearance
Sounds like you have original BHB pistons. They were designed to run very close tolerances around 1.5 thou off the top of my head however others may chime in with a definitive later. There maybe some specs to be found in the archives google archives.jampot.dk
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Re: rebore piston clearance
thanks for that. Yes they're BHB, these pistons have lots of numbers on them. Apart from +20 they have 022669 ,W151,L60.
No idea what they're for..
Cheers.. Paul
No idea what they're for..
Cheers.. Paul
- GSAX1
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Re: rebore piston clearance
I installed mine with a clearance of 0.03 mm / 0.0012". No problems and no tightness. F.W. Neill says in his book that clearance on the wire-wound pistons for the 500 twins was 0.0009" when new.
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Re: rebore piston clearance
Wow... Thank you. That is close.. Is that overall or per inch of piston.
Regards.... Paul
Regards.... Paul
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Re: rebore piston clearance
if you look at the user manual for 51 G9 twin it gives piston diameter measurements of 2.5984" on standard at bottom of skirt and , bore of 2.6" that would give .0016" clearance, so provided you have wire wound pistons then this is what you should aim for .
http://archives.jampot.dk/book/Owners_m ... Manual.pdf
http://archives.jampot.dk/book/Owners_m ... Manual.pdf
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Re: rebore piston clearance
OK once again thanks.
Cheers
Cheers