rattling sound

hey all,

my bike seems to have devloped a rattle sound. its a very fast rattle and seems to be coming from the top end :thumbsup:

it runs really well and runs like a scalled cheetah, but starting has become increasingly hard, time for some work?

if it is time, ride 'er til she pukes or fix now and miss some ride time? i wasn't planning on anything til winter.

EDIT: the rattle is not at all times.

This sounds similar to what I am looking for info on.

I am looking at a 2002 with the Bondi engine in it. It seems to have a real knock at idle and I am not sure if the premium pump gas is good enough for it.

does the rattle seem to get louder or faster as the bike is revved? if so, i would suspect that the spring holding the pipe on are worn out. grab them as you run the motor to see if it gets better. if it does, the simple fix is to put a length of fuel line over the spring to cushion them on the pipe...

I was with Zero and the sound seemed more internal than the pipe and we did try to hold the springs,pipe kick start etc. as we were idling the bike and the sound was still there.

Piston slap possibly. May be time for a new top end.

Mine had a real loud clank (more like "ping") noise at idle that would disappear when revved up. It ended up to be my RV valve that was not working and was stuck open at all time. Here's the noise it was making.

CR250 noise

When I removed the RC valve cover and closed the power valve manually, the idle noise completely stopped.

It's probably not your problem but it's good to know. :thumbsup:

P.S. If the rattle happen when you are hard on the gas, it's probably detonation.

That may help me as the noise is at its worst when the bike was at an idle. The link to the sound isn't working though.

That may help me as the noise is at its worst when the bike was at an idle. The link to the sound isn't working though.
How about now? :thumbsup:

yep that worked..

Hard to say if it is the same sound, either way I will open it up and check the power valve to see if it may be the problem.

May be a long shot but make sure the lock collar on the shock is tight.

the noise is only at some RPMs at some times, there seems to be no rhyme or reason to this sounds. at idle it sounds normal so i though piston slap is out of the question?

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