topend rebuild

[rhys96]

hi am upgrading my banshee pistons from stock to 65mm can anyone give me an idea of what the bore clearance needs to be.

thanks

[sleeper06]

If your bike is stock with stock stroke crank it's 64 mm if the top end hasn't been touched either way you need .003-.0035 clearance piston to cylinder with a wiseco or wsm forged piston

[Jereme6655]

along with what sleeper has said....you should not be just randomly enlarging the bore of your cylinders in search for more power.  You wont see anything worth considering a gain.  Bores should be saved for worn out cylinders, or cylinders that have seen catastrophic failure. 

[Young Guns Racing]

Jereme is right, my stock cyld 4 mil setup is only a 64.50mm bore and it hauls my 220lb ass just fine. Just punching an engine over for sheer displacement gains is not worth the life loss in ur cylinders. A nice set of pipes, good intake, reeds, cool head with custom domes and port work will probably put u close to wherever you want to be hp wise with a stock cyld engine

[WINDYCITYJOHN400]

And you should not bore the cylinder till you have the pistons in hand and VERIFY the TRUE piston measurements. THEN figure the bore from the true size of the pistons. EACH piston. 

[troyzstang]

^^^ Exactly. My local guy won't bore cylinders without the replacement pistons in hand. Plain and simple.