77 CB550K Camshaft/Head Wear Inspection (WITH PICS, OPINIONS NEEDED!)

Hey guys,

Coming up to buttoning up my 77 CB550K pretty soon (hopefully, knock on wood). Just taking a look at my camshaft and the bearing surfaces of my head, and was wondering if you guys saw anything out of the ordinary. It's my first rebuild and I really want to do it right. I see a little bit of wear on the head bearing surfaces, but I wanted to get your guys' opinion. How do the rest of the surfaces/lobes/camshaft look?

I bored by engine out to 600cc (not the Dynoman kit) but am also wondering if the 550 cam would still be appropriate to use, given that most other people with a 600 overbore usually go with the 650 cam.

I hope that pics are OK quality, your opinion is invaluable to me, thanks so much in advance!

Paul

The cam lobes look clean but they also look scarred and pitted in the pics (to me). The surfaces should have a very polished appearance... they should be much smoother and shinier than a freshly honed piston cylinder for instance (but don't expect them to ever look like chrome).

Don't used any kind of sandpaper or power tool. You WOULD NOT want to try to remove metal from the lobes to eliminate the scars and pitting (the cam will be ruined if you removed anywhere near that much) but it looks like they could be a lot smoother with polishing.

Valve springs exert a LOT of force to keep lifters against the camshaft at high revs (so your lifters won't float) and any imperfections in the camshaft lobes or lifter faces will expedite wear under that constant force. If just one fails you've got to do all the headwork again.

After the camshaft is installed in the head coat the lobes with lifter lube (some people just use a bit of grease) before installing the lifters. The lube will protect the cam lobes on initial engine startup until the engine oil makes it up through the oil passages to the head & valvetrain.

Just my opinion.

I also have a 77 550k that I have been piecing together (I bought it in pieces) I am curious did you measure the lobes on your cam? How is the wear on them? What made you decide to bore the cylinders? I am just about at the stage you are, my cam looks similar if not a little less wear than yours and the seats were worn similarly. The lobes were .01" off from what the manuals say they should be and I am worried that I will have to replace it.

Surfaces look good enough (my opinion). Lube the lifters and cam as described. I did the overbore rout as well. I ran it with the 550 cam at first. Wasn't really happy with the results. Got more "push" from the engine but really didn't get the results I wanted. A year later I came up on a reasonably priced 650 cam. It did the trick. Bike really accelerated like I wanted it to.

Note- after my bore it took quite awhile for me to find the right jetting. Throw the standard 550 jetting tips out the window. Only way I figured it out was to buy a set range of 5 and install, tune and tinker until I found the sweet spot.


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