Topic: New Bike and Im Worried

[campbmic]

Well I just bought a 1975 CB 550 when I got it, it was completely abused. I finally got it up and running but it idles very very rough and sounds pretty terrible. It also has smoke coming from the exhaust. I took the carbs off right after running it and there was smoke coming from the #1 cylinder on the carb and exhaust side. I'm very worried that this bike is just hangin on by a thread and that it will soon lock up.

1) Before I put anymore money into it what can I do to make sure that my engine isnt toast? I'm not for sure if its a critical issue that is about to seize the engine or if its just something out of tune.

2) Consider the most abandoned neglected CB550 you've ever seen. What should my next steps be to getting it roaring and ripping down the highway?

Thanks!

[scunny]

give it a full tune up, and clean those carbs

[fmctm1sw]

What was the compression?

[TwoTired]

Compression test, and/or a leak-down test is a pretty good indicator of current mechanical health.

What color was the "smoke".

Blue - oil
Black - soot (unburned hydrocarbons in suspension)
White - liquid vapor (water usually, but can be atomized fuel.)

Were all the head pipes hot (evenly) when you had it running?

What do the spark plug deposits look like?

were all the tune up items addressed?
How well can *you* run with one lead shoe?

[shizzomynizzo]

Definitely do a FULL tune-up.

New points and condensers, new plugs and caps (and trim down the wires 1/4 inch or so to get fresh copper, adjust valves, adjust cam chain, CLEAN CARBS, then RECLEAN CARBS, and finally CLEAN CARBS AGAIN.

I cleaned the carbs 3 times before I got them perfect. pull all the jets out, run some copper wire through them to ensure nothing is clogging them. Set the floats (12mm I believe on the 550) ensure the float needles work properly. Buy a couple cans of carb cleaner and go to town on them!
you don't need a carb soak unless they're REALLY bad.

After all that's done, you're ready to sync the carbs.

If you have access to a compression tester, go ahead and check the compression...either way you will have to adjust the valves.

If the bike has under 50K i wouldn't worry too much about the internals, these motors run forever!

If you don't know how to do any of the above tune-up procedures, search...there is a lot out there. Download the manual and read.


Mine was in a similar situation when I got it. It was able to get it running on two cylinders, and it sounded like there was loose metal in the engine. After adjusting the cam chain and doing ALL the procedures, it runs like new.

Good luck

[Johnie]

What makes you say "completely abused?" These bikes can take a lot of abuse, minus running real low on oil. These bikes can site for years and years and many of us still bring them back to life with a routine clean up and tune up. Don't give up on her man. Just needs some TLC.

[the technological J]

check ur oil too! throw some in the intake itt will assure some oil is lubing it.... and it will burn out( and smoke a little)