Engine rattle

**baffa** · 26th June 2012, 15:10

Penny for your thoughts.

I has a 97 CBR900RR, with somewhere between 90-110km on the clock (speedo isnt original).
It runs very well given its age, but lately has taken to giving a light rattling noise at low revs, especially idle.
Once its been ridden for a few minutes and fully warmed up, it goes away, and runs fine.

It sounds a little like the noise the cam chain tensioner made when it was starting to wear out (replaced recently with a second hand item). So I figured that what it was, just for some reason the cct was dying a slow painful death, but it only does it on warm up.
So I figure it cant be anything too serious, but any odd noises are always a cause for concern.

Anyone had anything similiar?

**ducatilover** · 26th June 2012, 15:40

CCT would be my first guess.
How far has the chain stretched?
Valve clearances?
Any odd looking Leprechauns hanging 'round lately?

**Fast Eddie** · 26th June 2012, 15:51

mine did this too bro, way at the start when the cam chain itself was stretched (in hindsight)..

at first, the tensioner can handle it, especially once warmed up it seemed to go away, but then it started intermittant rattle even when warm. just at idle, sometimes it would sometimes it wouldn't. come and go.

then it just rattled all the time at idle hah..

I recon keep an eye on it - you might be due for a cam chain itself, I think they only good for 50ish thou kms.

if you don't want to destroy another tensioner sooner rather than later maybe.. once the chain gets loose enough the tensioner has to work awful hard - I think thats why I chewed through a few of them in a few months.

but it could be anything

I once had a rattle at idle due to a screw inside my air box..

**FJRider** · 26th June 2012, 16:14

Find a short length of garden hose and stick one end of it to your ear. Use it like a stethoscope and move the other end around untill you find the source of the sound. A better educated guess would result.

**baffa** · 26th June 2012, 17:40

Cheers for the feedback all. The other day I ordered a tensioner from Honda, just to see if it would go away, seeing as the tensioner Fast Eddie kindly gave me is probably kinda old. Only cost about $100, but 3 weeks ex japan, so happy to pay that sort of money, and fit one brand new, and see how far I get. If it wears out after 5000 kay then I know I have to replace the chain and slider/tensioner thingee.

Will update once I fit the new tensioner and see if it fixes the problem.

**Gremlin** · 26th June 2012, 17:54

Does it make the same sound if the clutch is engaged?

**Fast Eddie** · 26th June 2012, 20:58

Originally Posted by baffa

Cheers for the feedback all. The other day I ordered a tensioner from Honda, just to see if it would go away, seeing as the tensioner Fast Eddie kindly gave me is probably kinda old. Only cost about $100, but 3 weeks ex japan, so happy to pay that sort of money, and fit one brand new, and see how far I get. If it wears out after 5000 kay then I know I have to replace the chain and slider/tensioner thingee.

Will update once I fit the new tensioner and see if it fixes the problem.

good luck

sounds like you might be embarking on the same mission I did

for some reason the tensioners honda supplied me were much closer to the 200 dollar mark. wankers.

I think I bought 3 of them, plus the original one I threw out, so went thru 4 I guess. the one u got was the last one I bought before buying new tensioner and then new cam chain after the noise came back after a month or so, few hundy kms or riding.

the new tensioners seem to be able to keep a loose and tired chain quiet for a while.. but yea - noise might come back!

you coulda chucked the bolt back into the one I sent u, run it as manual quickly to see if noise went away. if it did coulda run it for a week and see how much u have to adjust it, if ur adjusting it regular then I would be safe to suggest the chain was buggered.

but yea, hope the new one sorts it out for u!

(cam chain ended up being cheaper than a tensioner(s) for me in hindsight, think it was near 200 per tensioner, and only 100 for the cam chain itself)

good luck

**spanner spinner** · 26th June 2012, 21:19

the cam chain is stuffed, the noise you have discribed is classic worn out cam chain noises. A new cam chain is cheaper than several tensioners as a worn chain kills the tensioner units.

**baffa** · 27th June 2012, 16:53

Yeah tried with clutch in and out, its not the clutch basket.
For $100, im happy to try the tensioner. If it does it again, the chain, the slider, and tensioner will get done.
I wonder how much the big end bearings would cost to do, just for safety's sake