I have installed a new camshaft in my 1965 CB77 motor but now I have a concern about the state of the rockers. This engine was previously rebuild by a bike shop before I bought it and the invoice stated that they had 'refaced' the rocker arms and camshafts. The bike has only run 100 miles since then. On striping the engine for other reasons, I found the camshafts were damaged and had clearly been ground down. I replaced the camshafts.
I enclose a photo of the rocker arms and they are consistently showing a wear on one side.
I think it obvious that I should replace these as well as they will likely damage the camshafts. Before going to that expense, I would be pleased to have some guidance from anyone with this experience.
They are the old type without the oil hole in the contact face. Interestingly the right inlet rocker is slightly different with a narrower contact face and machined step in the journal.
Thanks in advance for your help.
Rocker Shaft Issues
Rocker Shaft Issues
Gordon
At the very least you have a mismatched set. The third one from the left is an early Dream rocker and shouldn't be there. Looks like the upper one in my pic but I can't quite tell. They have a narrower, longer pad and that strange 'bird wing' shape which is probably not stiff or strong enough for the sportier CB72 cam.  The fourth one looks like it has been welded and ground somehow and they all look like they have been re-ground on the pads but not done parallel with the rocker shafts. In my opinion the later ones are not better. The oil feed hole in the pad breaks up the lubrication surface rather than improving it. I could probably find you some better ones...... G '60 C77 '60 C72 '62 C72 Dream '63 CL72
'61 CB72 '64 CB77 '65 CB160 '66 Matchless 350 '67 CL77 '67 S90 '77 CB400F
G-man and Old Scrambler, Thanks very much for your helpful replies. Clearly this engine was built from a box of bits with supposedly the 'best' chosen for the rebuild. It's not the first horror I've found.
I will check the rocker shafts again carefully before reusing them. The ODs are within the MM limits. I would not have known that one on the rocker arms was from a Dream. It's a pity the re grinding was badly done on them all as it could have recovered the CB77 parts. I will replace them all as a job is worth doing right at this stage. I have seen the thread on the later oil hole type rocker arms. Rather surprising that Honda made a change without testing it extensively. But as always, real in service experience is the best testing ground and the evidence is there to prove they are not an improvement. Now that I have stripped the top and bottom ends, I may get the crankcases, barrels and head agua blasted. Also it's the oppertunity to check the crankshaft. G-Mans restoration has inspired me! Thanks again for your advice. Gordon
Just checking that you know that the exhaust and inlet rocker spindles are slightly different diameters. I cannot remember which side is the bigger but it's something like 10.5 and 11mm on the ends... I have reamers to clean up the bore if they have been badly drifted out at any time..... Let me know if you need any help on the rebuild. Happy to help. G '60 C77 '60 C72 '62 C72 Dream '63 CL72
'61 CB72 '64 CB77 '65 CB160 '66 Matchless 350 '67 CL77 '67 S90 '77 CB400F
Gordon
Sensible. Your experience and that of several others here reinforces my position to never buy anything that has been 'professionally' restored. The dictionary meaning of 'professional' is just a person who does things for money, it does not imply care or competence........ :-) G '60 C77 '60 C72 '62 C72 Dream '63 CL72
'61 CB72 '64 CB77 '65 CB160 '66 Matchless 350 '67 CL77 '67 S90 '77 CB400F
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