Cam chain - Can you hear yours rattling?

coupla possibilities:

it is your chain - check foer wheel alignment and change y=the way you adjust it to the way i adjust it = press down on the seat with your chest and check the flop with your right hand.

the other option is that your decomp is flopping at very low revs. the revs are often only this low when on tickover in 2nd gear etc when the revs can fall below idle.

the decomp will 'whack-whack-whack'.

regards

Taffy

Sometimes a new chain guide can be a source of chain slap until it wears a nice groove into the rubber block. To rule this out just remove the guide and go for a spin.

philis said:

Ive just checked the cam chain tensioner and its adjusting ok, although i poked my finger the hole expecting to feel the cam chain but all i could feel or see was the plastic guide, not the chain, is this normal?

Click to expand...

Yes.

I am guessing it is the drive chain hitting the frame. Seems to be worse at steady speeds, more noticable at lower speeds. I know the chain is on the right side but that is what it sounds like to me. Very common and very annoying at times.
Check for any witness marks where the chain passes the frame.

If you can't be sure it is the drive chain, there is a chance it could it actually be a real problem inside the LH engine cover? In there is lots of gears & **** like the kickstart, the primary drive, counterbalancer drive, clutch etc. Don't mean to suggest the sky is falling, but if it worries you it might be worth a look inside the cover?

Does the chain look like it has actually been hitting the frame? It'd leave a pretty good mark if it was.

Phillis

i was doing a '04 650 yesterday and the camchain tension is completely used up! it's fully open. the chain, an IWIS is like new still. i suspect the chain has been rattling around. what i coiould do with is an old style tensioner with the blob on the end right now.....

i also checked and the auto decomp has been smacking hell out of the tiny bolt, it's almost 'D' in section yet it still hasn't broken - miraculouosly!!!!

the spring seems to be soft. now i don't do '04s everyday, infact it's only my 4th but interestingly, it's the third one with no tension adjustment left? now that has got to be a worry?

if not this, the only year that the quality IWIS chain was fitted (and it still is!) but the next year and thereafter with the cheaper DID chain?

anyway, having tightened a few decomps (try 20-30) in recent times i can tell that the OEM spring is too weak, that the decomp weight can flop around. that will explain the absolute battering the stop bolt has taken and may explain your noise phillis?

the golden rule with the decomp spring is that the long tail must point in the same direction on a parallel plain to the tail the sub-divides across the centre. it's about another 90 degrees of tension but is also 33% as well.

i'm going to put this up as a fresh thread as well.

regards

Taffy