2005 - 2007 cr250 cylinder measurement

Hey all, 

I recently got my cylinder replaced and in the meantime had the same company milled the base .030", I know that the 4 casting vent holes are slightly inconsistent from cylinder to cylinder but apon receiving my cylinder back it seems like there is still way too much depth to the holes compared to every other milled base I've seen, I was wondering if anyone had a cylinder milled or unmilled off a bike that could get an accurate top to bottom measurement of the cylinder so I can reference it to mine.



I sent you a PM

Ive done the same '030 base milling job on my 07 cylinder and the 4 holes were pretty much machined away to nothing. Recently i did a full rebuild on a mates 07 CR250 and ordered a stack of brand new OEM parts including a new cylinder.

His new cylinder was also machined the same '030 as mine and i was surprised to see that the 4 casting holes were still there and had plenty of depth left in them. The base machining was done by the same milling machine and operated by the same highly experienced machinist both times.

So, it looks like the casting holes are inconsistant and cant be used as a machining reference.

Anyway, hope this helps and good luck with the rebuild..........the base mod is a great thing!!




Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now