Topic: 1975 CB550 Rebuild

[atonparker]

Heyo. I'll introduce myself first: 22 years old, living in Ann Arbor, Michigan. I don't know much about engine or auto repair, but have been repairing bicycles for a while and know my way around a tool box/metal shop. And I've got the most important thing, elbow grease. So I guess I'll learn as I go. I bought this bike about 8 months ago for $400 and am just now finding the time (and money!) to get some work done on it.

Some specs:

• VIN is CB550-1222065
• EIN is CB550E-1059379
• Title lists it as 1975 CB550. Looking at the model guide confirms this, except the 1975 CB550 K1 didn't come in blue. I think the tank was swapped for a CB550F.
• Odometer shows about 12k miles
• Engine ran when I bought it, but only at 75% or more throttle. As I took it apart, I think some carb hoses were unplugged and spark plugs were bad. Regardless, nothing is seized.

Here are photos of the bike as a I got it:










Damage to the front fender.


Relatively clean engine, on the outside.






Wiring is mostly intact, but I'm pretty nerdy so I think I'm going to start fresh. Any project links for replacing/upgrading the entire wiring harness?


Front brake disk.




Rust on the pipes. One of them is completely rusted through. I'm going to have to buy new ones...I'm thinking 2-into-1s.




Rust on the rear suspension. Should I replace these?




Damage to the right side of the engine (clutch case cover?).


Damage to the right side of the tank. Starting to look like she was laid down at some point.










Yep, definitely a front end crash. The steering limiter is bent. Any idea how hard of a crash would cause that? Hard enough to crack the frame?








Whoops! The nut was seized and the bolt broke. Will I have to weld on a new bolt?


Not too much rust on the tank.

[Gman]

Welcome to the forum.  You made a good start by posting lots of pics - we love us some pics!  

There's a ton of help here - use the FAQ section, do searches (use the google search feature - the other one is not working at the moment) and ask questions when needed and someone will pipe up. 

My 2cents - make sure your frame is straight before you get too far along, as you said it seems to have been in a dustup.  I'm def not an expert, so I can't tell you how, but if you check out some other builds that have had issues w/the frame, the consensus from all the guys that are experts is not to use a bent/warped/kinked, etc. frame for obvious safety reasons.

Good luck and enjoy the process!

Cheers,
G

[atonparker]

Thanks for the welcome and tip Gman. I'll definitely be checking the frame for trueness. I'm taking apart the front end right now, and the right fork tube is bent almost 5 degrees. The left fork tube, on the other hand, is nice and straight. Pics to come. Not sure which part took the load off the left fork tube...could be the frame, the axle, the triple tree. Hopefully I'll have the engine out within a week so I can do a once over on the frame.