Differences between C72/77 and CB72/77

[LOUD MOUSE]

They are the same other than the 60 issue which has 8 rather than 9 holes at the case side.
All the really early ones had 8 even the CB72. ..............lm

Hi all, Looks like my task of mating the CB77 top end onto a C72 bottom end would be quite difficult.
I understand from other contacts that the C72/77 barrels are slightly different than the CB72/77 in that the oilways/galleries are in different positions - anyone verify this?

I guess I will have to start looking for a CB77 bottom end.
Arthur

[CliffC]

I guess what I'm still trying to figure out is how this discussion on differences got put on the paint topic. Doesn't anybody read anymore or is it just me. cliff

[LOUD MOUSE]

I answer questions. ..........lm

I guess what I'm still trying to figure out is how this discussion on differences got put on the paint topic. Doesn't anybody read anymore or is it just me. cliff

[jensen]

Hi Arthur,

Please remove the left side cover of the head and take a picture of it.
If this cam is uncut, and doesn't have a gear on it, there is a good change that it has the C72 cam setup. It's also possible that the head is not a CB head but a CL head, with CL cams in it (heads are the same).

Like Ed (LM) said, the cylinders are the same, except early / late (8 hole versus 9 hole).

Best way to see what you have is disassemble the top cover and peak inside the head.

I don't understand why a mechanic would put an engine together that doesn't run (function wise), so I guess it will run, because he probably used a set of C cams instead of CB cams to work with the crank, or he shouldn't name himself a mechanic in the first place. How sure are you about his professionalism anyway ?

I also suggest that you read in a bit about these bikes, the bill silver books are a good start.

Jensen