metallic vibration sound on engine top from 4500 RPM and up

[jmtourn]

Hi, my bike has a metallic vibration sound on engine top from 4500 RPM and up, valve clearances are 0.10, and cam chain is new, and the tensioner works good (manual).
My bike is a gs425. What's the problem???

Thank you !!!

[shortlid]

My '80 GS850G does the the metalic rattle, Exhaust?

My '80 GS850G has a good condition GS1100G exhuast system on it. My Gs850G does this as well I think it is the exhuast resonating (sp.?)? :roll:

[jmtourn]

That's a good idea, but i don't think that's the problem, because my gs425 have the original exhausts.
Thanks.

[Anonymous]

Is the sound there regardless of load? Is it only there if you are using lots of throttle? What octane fuel are you burning? What do the plugs look like? What was the last thing you did to the bike before this started? Did it start suddenly? How many km.s are on the engine?

[jmtourn]

i have this bike since february. I change pistons, valves, and cam chain. The sparks are black (too much fuel), but ok. Maybe I'm not adjusting well the cam chain tensioner????, it's manual, and i adjust it not to make any noise when idle.

[Jethro]

Have the carbs been vacumm synched? Did you replace the cam chain guides when you did the cam chain?

My bike runs fine, but is a noisy bi-otch. Sort of the nature of 1/4 century old machines.

[jmtourn]

no, i'm going to do the carb synch this week, but i don't think that's the problem with the noise???. I don't replace the cam chain guides, that can be the problem, but they look good!!!. I'm going to look and see what happen.