85 2006 KX85 Big Bore

[James]

So my buddy is trying to find a piston for a 06 KX85 that has an over bore. He measured it at 52.57 which would be a +4mm over bore, stock is 48.50mm. The problem is that the biggest piston I can find is a +2mm (92cc). Are +4mm kits even made or did he just measure wrong, he wasn't using a digital caliper?

Thanks

 

[timoyz]

Could it be a KX100 jug? I don't know, just thought I'd throw it out there.

 

[James]

Could it be a KX100 jug? I don't know, just thought I'd throw it out there.

I think you're right, the numbers match up to a 100.

So I asked him if it could be a KX100 in a 85 frame and he said that they had blown the 85. So they got a new engine off of ebay, maybe they got a KX100 engine instead. He did say that it fit in the frame.

 

[timoyz]

I think the frames are the same, just a longer swingarm, and bigger forks.

 

[James]

I think the frames are the same, just a longer swingarm, and bigger forks.

You're right Tim I went over and looked at it, it looks like a 100 top with a 85 bottom.

Thanks

 

[timoyz]

"Gee Dad thanks! My 85 runs great since you rebuilt it."

That kid didn't know how lucky he was.