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Stock 2004 KDX220R. Is the bore size 69mm? Getting ready to order a Wiseco piston kit - any advice before I fire the bullet?

Get a top end gasket kit too.

69mm is the stock/standard bore size.

Given I haven't torn one of these down before (it's also been 30 years since I did an engine tear down Ugh!), it seems prudent to NOT order anything until this is torn down - agreed? Probably common sense, right?

I measured the bore on mine before I ordered my Wiseco top end kit with gaskets. I didn't know what the POs had done to it, so I wanted to be sure of the bore size first.

Captn Kirk wrote:Given I haven't torn one of these down before (it's also been 30 years since I did an engine tear down Ugh!), it seems prudent to NOT order anything until this is torn down - agreed? Probably common sense, right?

well you know you will need a piston and a gasket kit

My point though, is what size/oversize might I need? If you are intimating that the cylinder, if damaged, could be repaired with the end result back to 69mm, I get your point. Being old school, isn't there the possibility it could need an oversized piston ultimately?

you can't just bore a plated cylinder

If it is damaged it'd need to be rewelded and replated

You could go oversized if you wanted I guess but definitely not needed