CB KEY?

[therapture]

What is the CB key problem I keep reading about? I assume CB = Counter Balancer? I would assume again that they mean the half moon key that holds the counterbalancer on is coming losse or shearing off? And is it easy to check!? I just got a fresh cylinder and piston rebuuild due to a loose oil drain bolt, and really don't want to trash something for a 50 cent part!

[Scott_F]

Did you do a thorough search and read up on the subject? It is not a woodruff (half moon) key, but is 5mm square in cross section. It is not too difficult to check and replace. I highly recommend it. The key is on the end of the crank, under the gear that drives the CB.