Genuine yamaha oversize pistons

Blaner

Your Friendly South African Ambassador
Mar 26, 2008
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East London, South Africa
just a simple one guys, is it true that the yamaha oversize pistons (0.25, 0.50 etc) have slight dome differences to compentsated for the increased bore thus keeping the compression ratio the same?
 
no the piston will have the same angle (9 degrees if its a blaster) on all the pistons, if they changed the angle on piston the squish band width and height would changed and thats just not the case, the bore being increased by .020 or .050 is only going to affect compression a very small amount