Topic: 1977 cb550 more rebuild questions

[kakon864]

As I get closer to actually rebuilding my cb550's engine I got a few more questions.

One of the exhaust valves guides somehow broke when the valve seals were being taken off, so I need to replace that. I saw someone saying that you can use an intake valve guide instead of exhaust one and was wondering if that would be fine because the intake guides are a lot easier to find.

Since I am going to be rebuilding the top end should I throw new crank and rod bearings in while I have it apart (has 19k on it)? I think I have A crank bearings and E rod bearings if so ( will attach a photo of stamps).


The cam chain adjuster is in good shape other than the guide piece is cracked at either end, but seems to be attached well to the metal band. Should I replace this or am I fine?


Also when grinding the cam chain link off to free the engine up (piston was seized and couldn't get to the other cam gear bolt) I cut into a little bit of nylon on accident. I'm not sure if I should do anything about it or not, but in hindsight, I should have just bought the link breaker.


My final questions are the end of the sparkplug threads on the inside of the head seem to have taken a little chip of head out when being cut on all of them. Is this normal? From what I looked up on eBay a lot of heads looks like this.


Sorry for all the questions,
Thanks

[bryanj]

Fit a proper exhaust guide and it will need reaming to size by a PROPER motorcycle engineering shop and the seat recut, may be cheaper to get a used head as all 500 and 550 are the same.
The E is a weight code not a size code PLEASE read the Honda manual carefully to work out sizes which it probably wont need anyway.
Tensioner is probably OK but good pictures would help
You need a new cam sprocket, again 500 will fit.
Plugs dont go all the way to end of thread so probably OK

[bryanj]

On enlarging a lot the picture you have put up i would not use that tensioner, i know they are pricey but you dont want large lumps of rubber chewed up in the gearbox. I thought you meant small cracks at the very end of the rubber bit.

[kakon864]

Fit a proper exhaust guide and it will need reaming to size by a PROPER motorcycle engineering shop and the seat recut, may be cheaper to get a used head as all 500 and 550 are the same.
The E is a weight code not a size code PLEASE read the Honda manual carefully to work out sizes which it probably wont need anyway.
Tensioner is probably OK but good pictures would help
You need a new cam sprocket, again 500 will fit.
Plugs dont go all the way to end of thread so probably OK

Thanks for the reply. I think I will look at a new head, seems I can get one for a little over $100. Can I just replace the tensioner blade myself with this for example https://www.davidsilverspares.com/CB550K-1977-USA/part_224403/ ?

[bryanj]

Simple answer yes Dave Silver has a good rep for his replica parts