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Cylinder Head Interchangeable between Models?

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I'm considering trying to install a Rev3 250 top end on a 200. I have the cylinder and piston but not a cylinder head. Does anyone know if heads from other models or years will fit? I would like to buy a used head.

I'm not sure but I thought the 250/270 and 125/200 were different strokes. That means different cranks. You might want to look up parts breakdowns for the year bike you have and see what parts are shared and what aren't. Be a shame to take it all apart and find the cases don't fit or some other big issue.

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I'm not sure but I thought the 250/270 and 125/200 were different strokes. That means different cranks. You might want to look up parts breakdowns for the year bike you have and see what parts are shared and what aren't. Be a shame to take it all apart and find the cases don't fit or some other big issue.

According the the specs, the Beta 200 is a sleeved down 250. The GG "200" is a bored out 125. Looking strictly at part numbers, there is no commonality among any of the engine sizes. Interestingly, the 200 forks have a different part number also. Could this be different damping or maybe an older style fork.

I realize that this would be an experiment but would like to have a complete 250 top end to work with. Did the cylinder head bolt pattern change from Techno or Zero?

According the the specs, the Beta 200 is a sleeved down 250. The GG "200" is a bored out 125. Looking strictly at part numbers, there is no commonality among any of the engine sizes. Interestingly, the 200 forks have a different part number also. Could this be different damping or maybe an older style fork.

I realize that this would be an experiment but would like to have a complete 250 top end to work with. Did the cylinder head bolt pattern change from Techno or Zero?

I think you are correct in your first statement, as that is how they achieve a true 199 or so cc out of the 200 bike, same bottom as 250, at least that was true for Techno. They did a kit at one time for this, yet due to bore sizes and different squish bands and combustion chamber dimensions I would think the 200 head different, I doubt the 250 head would work properly on a 200 top, although it may run. Call Ron Commo? :thumbup:

Edited by copemech

The Rev3 brochure I looked at had the same stroke listed for the 125/200 and different for the 250/270 so that's why I thought different crank.

Yeah call Ron.

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