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Boring a engine .80 over?

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I want to learn the formula for when boring a engine over just so I know people aren't bullshitting me.

So say if I have a kx80 and I want to bore it .80 over. What's the formula to accommodate that? I don't even know if you can bore a engine .80 over I'm just wandering for educational purposes. Thanks..

-The brave may not live forever,but the cautious never live at all.-

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Bikes that have iron cylinders can be bored when worn out or damaged to accommodate a larger piston.  Usually oversize pistons come in increments of .010 up to .080.  I might be mistaken but I think .080 was the largest piston generally offered OEM for overbore.

 

On your 80 .080 would be 2MM or about 85cc.  Once you reach the overbore limit you have to resleeve the cylinder or replace it.  Most newer bikes have plated cylinders that can be used over and over with the stock bore size piston so oversized pistons are not necessary.

 

.080 would not be considered a "performance" mod.  Just routine maintenance on a worn cylinder.

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Bikes that have iron cylinders can be bored when worn out or damaged to accommodate a larger piston. Usually oversize pistons come in increments of .010 up to .080. I might be mistaken but I think .080 was the largest piston generally offered OEM for overbore.

On your 80 .080 would be 2MM or about 85cc. Once you reach the overbore limit you have to resleeve the cylinder or replace it. Most newer bikes have plated cylinders that can be used over and over with the stock bore size piston so oversized pistons are not necessary.

.080 would not be considered a "performance" mod. Just routine maintenance on a worn cylinder.

Ok thanks because my buddy is buying one and it's a 89 kx80 Jw what it was lol thanks man

-The brave may not live forever,but the cautious never live at all.-

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If I was going to bore it I would have it bored as little as possible. A nice perfectly round cylinder a new piston and rings should get the compression up nicely. That leaves some meat in the cylinder for future boring and should run cooler also.

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