I would appreciate some opinions on my first 76CB550F rebuild/restore:
1. At 18k miles bike/engine had been parked since early 80's I believe. Spun freely but highest compression reading of any cylinder was 60psi with one as low as 30. #4 wouldnt even blow my finger off the spark plug hole. As bike was pretty crusty I assumed the rings were corroded and frozen or something. Engine is out now so I pulled the head and cylinders and other than some major carbon accumulation the pistons and rings are perfectly fine. Head gasket looks fine no burn thru. I haven't gone in to the valves yet but what are the chances that my super low compression was all valves?? No way right?? So WTH?
2. There are no visible leaks on this (untouched since factory) engine other than around the sprocket area which I assume is mostly chain grime. The inside of this engine is clean as a whistle. I was going to go thru the whole engine as a learning experience if nothing else (although not my first engine this is my first one on a bike) but am I crazy to break this case open just to look at the dang crank and go ooohh coool? What is going to start leaking the minute I put it back in my nice newly restored frame right? Am I better off risking new leaks from breaking it open, or risking leaks from old seals/gaskets because I didn't break it open? Anything else in the lower I should worry about at such low mileage?
3. Although polishing the covers is going to give me tennis elbow, the factory paint on the head and jugs is beautiful. The main crankcase however is not so nice. I was going to soda blast the whole engine and give it a fresh coat. But is there a paint out there that is a perfect factory match so I can just paint the crankcase only? What about poor paint performance versus the factory finish? Is that an issue? I can just paint entire thing but don't want to regret soda blasting off that nice factory coat on the jugs and head...
Any commentary on any or all above much appreciated. Thanks!
