YZ 426 Bore out or buy new cyliner?

Hey guys and gals, I've got a YZ 426 that I have to do some work on the cylinder, I need to eather buy a new cylinder or bore it out and sleeve it to fit the new piston. Someone had told me that because of the nickle coating or what ever it's called, if I bore and sleeve I could loose power, Does anyone know if this is true and if so would you really notice it if your not on the track. I'm not a Pro by any means but I do run the bike hard.

It would cost less to sleeve it but would this hurt reliability. Could I bore it out to be a 450?

Just wondering if anyone has had to deal with this.



It can be punched and renaik'd to run a 97mm piston = yfz444.

Did this to my old 2000 years ago and never had any issues. Made it pull a little better down low. Mid and top felt about the same.

Did you have to change anything else, cams or anything?

Did you have to change anything else, cams or anything?

Nope. All the stock internals remain.

I installed the 03 450 decomp cam while I had the motor torn down, but it was not necessary.

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