yes they do have the .110 overbore but unless your just going to race it, its more hassles than its worth, as the cylinder walls get very thin when doing a bore that big, and dont disperse heat as well from the piston. or so ive been told. also if your doing a bore job that big, you get a motor that is more finiky when it comes to temp changes. and need to mess with your carbs a lot more.
.60 is not too much, but i would stick with whatever you need to bore it to get the next size bigger pistons in it to freshen the motor, that way should you ever have to do it again you have room. boring .110 is the total amount allowable then you have to start over with new cylinders, or sleeves.(cant remember if those were sleeved or not)
Thanks guys. The reason I asked is be cause I rebuilt my friends 600 and I bought the pistons from Dennis Kirk. But the bore was 65mm but the pistons they sent were only 64mm. The stock pistons were 65mm. I used them thinking they would expand and compensate for the diffrence but now the motor doesn't even make enough compression to start. It's a parts-unlimited screw up but they won't fix it. Now my buddy can buy a complete pro-lite piston set with gaskets and wristpins for $99.00. And they are .60 over
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