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need to know bore sizes
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Posted by: zach450rnut

i need to know what the bore sizes are for std 20 over 40 over etc.. let me know guyz thanx

Posted by: screaminta

Hey, its pretty simple to transfer from inches to mm,
1"=25.4mm.
So, .010" would equal .254mm because you would multiply the .010" by 25.4mm. Whatever you have in inches gets multiplied by 25.4 to get mm. Also, the "20" over is actually 20 thousandths of an inch over bore or .020". It may sound confusing but its not. Anyway, standard 250r bore is 66mm. "10" over would be 66.25mm, "20" over would be 66.5mm, "40" over would be 67mm etc etc.

Posted by: EXtreme-

http://www.pistons-online.com/motor...da&st=54&end=55