Topic: Hey listen to this!

[Dr. Noisewater]

I started it up this morning for the first time in awhile, and it's only my second time ever starting this thing. It's a barn find that I'm bringing back. It made this noise the last time it ran too but I adjusted the cam chain tensioner and the valves - both of which didn't take nearly any adjusting, but I was still hoping that would've fixed it.. but no.

1975 CB550 Engine Noise

[nccb]

IDK, pull your clutch in and see if the noise is still there or becomes less audible.

[Deltarider]

Idle should be adjusted to at least a true (!) 1000 rpm, make it 1100, to avoid rattling.
How did you perform adjusting the camchain? Best is Bryanj's way as described in the FAQ. You may need a helper though.
Start with the easy things.
Check (in the dark) for sparks flying between plugcaps and/or HTleads and the head.
Does every carb receive enough gas?
Then there are the more difficult things like checking the ignition timing, inspecting the slow jets for cleaness and in the end - when all is done - a check if the carbs underpressure is within 3cm Hg of each other.

[ANDY W]

did you vacuum sync the carbs?

[lucky]

Did you adjust the cam chain tension by using a workshop manual, or what someone told you?

[Dr. Noisewater]

The carbs were rebuilt and sync'd by harisuluv, who did a phenomenal job. One of the bodies was trash and he was able to find a donor body and set me up with an immaculate set of carbs.

I adjusted the cam chain by way of SocoMoto's video on youtube. My Haynes manual just says to adjust it, and doesn't explain how to. I'll check out Bryanj's method though. True about the idle. I'll get my tach hooked up and try to set it to 1100 and see how it does.

The clutch cable was disconnected because it was way too tight and I didn't have time to mess with it before work. I'll try to get it operational before next time.

[iron_worker]

Idle is too low it sounds like especially since you can hear it die off at the end.

Did Harisuluv sync the carbs on your bike with a vacuum gauges or did he just bench sync them in his shop and then send them to you? A bench sync just gets you close so you can fire the bike up. You still need to sync them with vacuum gauges afterwards.

IW

[Dr. Noisewater]

I just asked him and it was just the bench sync. I was unaware they needed a vacuum sync after the fact.

[bjbuchanan]

These bikes have an audible noise that disappears when the clutch lever is pulled in. It isn't horrible sounding and really loud but is present. A quality bench sync helps but vacuum sync gets that silky smoothness

Idle the bike at 1100~ like a honda sohc4 should idle at, not a Harley. That will help with smoothness quite a bit

[Stev-o]

+1 turn the idle up. Set it once the bike is fully warmed up.

The carbs have to be on the bike with it running to sync it, you 'll need gauges.

[Mooshie]

When you turn the idle up (I have a 550 as well and mine runs at 1000 but 1100 would be just as good) make certain it is warm and to blip the throttle after you adjust to make certain you don't just keep turning it and then it is too high.  You can set it without a tach fairly easily if you just listen.

[Dr. Noisewater]

Thanks guys, I'm going to get my tach hooked up tonight and maybe mess with the idle if I have time. Otherwise it'll have to wait til the weekend. I'll keep you updated.

[Stev-o]

Thanks guys, I'm going to get my tach hooked up tonight and maybe mess with the idle if I have time. Otherwise it'll have to wait til the weekend. I'll keep you updated.

I set my idle by ear. Keep in mind that may be off by up to 10%.