Difference between A & B cylinders

[broken1]

I know that this has already been asked by another member but I didn't see the answer & now I can't find the thread using the advanced search. The cylinder on the 86 trx i recently got has an A on it that was written with a yellow paint pen. What does this mean? What's the difference between the A & B cylinders?

[atvmxr]

are you asking the same question on both sites to see if you get a different answer?  :playful:

[broken1]

are you asking the same question on both sites to see if you get a different answer?  :playful:

Not at all. I remember seeing a thread about it & thought it was on this site. I saw the other members question but no one had replied at the time i saw the thread & it made me curious what the answer was because my cylinder has an A on it. I thought the thread I saw was on this site but I guess not:confusion:

[mennis1971]

It was on the other site and there is more of a difference than just the pistons as it was recently answered over there. I'll admit to not knowing  the differences, but I've heard the A has more potential from my builder. Neil made a comment on that thread too btw. That cylinder may have more potential when porting/ported, but you'll have to find someone that knows enough about them to find that potential. I wouldn't think it's gold or anything, but it is more rare.

[udontknowme]

difference in A and B on ktm is .0004". honda is probly close to the same

[broken1]

It was on the other site and there is more of a difference than just the pistons as it was recently answered over there. I'll admit to not knowing  the differences, but I've heard the A has more potential from my builder. Neil made a comment on that thread too btw. That cylinder may have more potential when porting/ported, but you'll have to find someone that knows enough about them to find that potential. I wouldn't think it's gold or anything, but it is more rare.

For some reason I thought the thread was on this site but after atvmxr asked about my question on the difference between the 2 cylinders I looked at the other site & found it. Thanks for the help guys.

difference in A and B on ktm is .0004". honda is probly close to the same

[rsss396]

The differance in the a and b cylinders is the bore size the B cylinder will be .015mm (0.0006") smaller than a A cylinder