Engine tick at idle

Hello,

Ive read through a bunch of posts concerning a ticking coming from the engine during idle. Its too low of a frequency to be considered valves so Im thinking its the cam chain. The bike is a 1984 ZN750 so it has the auto tensioner. Im thinking of just putting the manual tensioner in it to see if it makes a dirrerence. What do you guys think?

Things to note:
-noise disappears at higher rpms and appears more prominent during colder starts.
-bike runs great (crisp throttle response, lots of power throughout the range, no flat spots, etc.)

Thanks,
Curtis

Hey Big wheel, to my ear, a loose cam chain is much more like a rattle than a tick.
But it could be.
Just because it has a auto tensioner, doesnt mean that is working correctly. Maybe take it apart, and make sure that it is functioning.

Also, noise probably is drowned out by the engine noise at higher rpms.

just my .02

MJ

small exhaust leak can sound like a click.

bountyhunter wrote:

small exhaust leak can sound like a click.

+1

After checking and gently snugging exhaust clamp nuts, could remove spark plug caps one at the time which might help determine which cylinder has the exhaust leak, as lack of combustion may reduce the ticking.

Good Fortune!

+2

Exhaust leak may be the issue, and a cheap fix.

I use 1/4" fuel line on my mechanics stethoscope, but just the hose to you ear will work really good to find a noise. Have you checked your valve clearence? How many miles is on it? You can replace the springs on the auto tensioner cheap.

synch your carbs

PLUMMEN wrote:

synch your carbs

and get a manual

It makes a huge difference to perform all of the necesary maintenence.

Thanks everybody!

I have a service manual (both clymers and haynes) but a factory one would be perfect. I checked for exhaust leaks and there doesn't appear to be any. I have just installed the manual timing chain tensioner but I haven't thrown the carbs back in quite yet (Ill post an update in about an hour).

Some more background info:

-its got 36,000 kilometers on the odo.
-valve clearances within spec.

why did you use a manual tensioner?

"I have just installed the manual timing chain tensioner"...

Did it Ticky-Tick pre this installation?

Big_Wheel wrote:

I have just installed the manual timing chain tensioner

One thing to remember... the manual tentioner does need to be periodically tightened from time to time.

:laugh: Hence the manual part.