76 rm125a cylinder

[Paul Jeffs]

Hi
I am looking for a cylinder for my rm125 a and have been offered one that looks visually the same from a photo. Only problem is he claims the bore is 55.5 mm. As the stock bore is 56mm I'm guessing it's off a b model. I've asked him to double check his size and he still gets 55.5. Other than the bore and stroke what if any differences visually are there between the two. Thanks Paul

[John Orchard]

If the barrel has an un-bridged inlet port, and T shaped exhaust port it is an A barrel.  I just sold an RM100B barrel (RM100B & RM125A both have 50mm stroke so same port timing) that was a hint under 56.00mm, the 100B's still had 123cc cast into it; Suzuki must have used the same mould for both bikes but pressed in a smaller ID liner for the 100B.

[Paul Jeffs]

Thanks for the info John . The inlet port is bridged and exhaust ports square so it must be a B barrel. Thanks again for your help. Paul