CR250 "A" clyinder vs "B" cylinder. How to indentify.

[Mike[socal]]

How do I indentify what cylinder("A" or "B") I have for a 2001 cr250?

Thanks,

Mike

[mtk]

It's stamped on the cylinder. For the life of me, I can't remember exactly where, but it's on there for sure.

As I understand it, the vast majority of them are "A" cylinders.

[Mike[socal]]

Do you remember if it's visible from the outside?

[ossagp]

I have a cr250 cylinder in my hand, and there are stampings on the righthand side transfer port bulge,,,wish i had the bifocals on,,i thing it is in that string,,there is also a stamping under the reed chamber,,cant make out either with these glasses, but look at those points.

An A piston works well in a B barrel and a B will fit nicely in a worn A for the most part. If I recall there is only about .0004 of an inch difference and it is at the skirt of the piston.

[ossagp]

Ok,,better now,,the right glasses,,,look on the boss for the left rear stud. There is a definite A on the 2001 that I am now holding.

[Mike[socal]]

Awesome! Thanks for the info. I'll look tonight when I get home. I just put in a wiseco top end and was curious which cylinder I had.

[Mike[socal]]

Found the marking. It's near the bottom of the cylinder on the shifter side towards the intake. I have an "A" cylinder. Thanks for the help.