Quick question??

[sirdirk007]

I have just bored my cylinder on my 250r motor to 71.2mm I am now in the process of buying a new piston and rings. Do I need to buy the same size piston because they machine it to fit or do I buy a smaller one? This may seem dumb to you all but to me it could be a $80 dollar mistake.

Thanks for the help guys.

PS I have an 82 honda 250r I am still selling. The registration will be current soon and it needs the rear brake master rebuilt, a headlight, and axle nut on rear. It runs strong and great other than that and I borrowed an axle nut from my other bike and it rides great too. Suspension is good. I am asking $800 so let me know. Oh it has new rear plastics too and a set of new holeshots that have not seen dirt yet.

[atctim]

Who bored your cylinder? the best person to ask would be that person - the machine shop that I take my bore jobs to does all the mic work for me and tells me what size piston to buy. Yours should do the same.

[NINJA]

I never bore a cylinder until I have the piston sitting right there that I'm going to put into it. I measure my piston and then bore accordingly. You'd be surprised sometimes when they're not exactly the size they say they are. A good machinist will request your piston with the cylinder.