Odd noise on 900 cbr

[el_scor_cho]

Hey all, recently my 1997 cbr started making an annoying noise when slowing down. for eg, pulling up to the lights from about 20k/hr to just before 0 there is an odd noise sounding like chain drag but commin from the engine,

usually stops before i come to a stop but the other day it continued even when in neutral so something to do with engine. chain is right tension and wheels alligned correctly. any help or anyone with exp with such an issue would be awesome

[Coldrider]

clutch rumble?

[el_scor_cho]

could well be i wouldnt know. how do i check that out?? just had plates and springs changed a few months ago. ta

[Coldrider]

when coming to a stop from 2okph, pull the clutch in and coast, listen for the noise.

[Ragingrob]

My clutch sometimes gives a grinding kinda rumble noise when pulling away from 0kph if I don't ride the clutch at all... Sounds like it could be a similar thing... Gonna keep an eye on this thread :niceone:

[el_scor_cho]

sorry should have mentioned that its only noticable when clutch is pulled in. usually stops if i throw her into neutral but has been making noise regardless lately.
springs? plates?

[Coldrider]

Hondas have extremely quiet engines which make small noises sound bad.
Someone else may be able to help.

[el_scor_cho]

its not too quiet at all, thats what worries me. thanks for the help coldrider

[Spanner Man]

Hi,

Could be cam chain. Try revving the bike in neutral on stand. If the rattle goes quieter as the engine revs increase and then gets louder as the decrease then its prob cam chain as the chain whips from driving in one direction ot the other. Quite common on mid to late 90's cbr's at about 50,000 kms onwards.

[steve_t]

Hi,

Could be cam chain. Try revving the bike in neutral on stand. If the rattle goes quieter as the engine revs increase and then gets louder as the decrease then its prob cam chain as the chain whips from driving in one direction ot the other. Quite common on mid to late 90's cbr's at about 50,000 kms onwards.

+1 for cam chain/ cam chain tensioner as good place to start looking

[el_scor_cho]

hmm could be an idea, will have a look. i have never heard it make this noise when shes not moving however

[Coldrider]

front disc pads rubbing on the disk?

[el_scor_cho]

naw def not that. think your clutch rumble idea may be along the right lines, only occurs when below 2k revs and sounds in time with the engine. ta for the ideas

[p.dath]

When I was trying to locate a noise on my bike once I search on You Tube for videos. For example, try searching for "motorcycle cbr cam chain noise", or something similar.

You can often find videos that people have recorded of what something sounds like when it is broken.

[kevfromcoro]

+1 for cam chain/ cam chain tensioner as good place to start looking

cam chain tensioner...
those bikes are fairly comon to let go. the tensioner...
not a big job to change it......

[el_scor_cho]

cool looks like the tensioner after a bit of reading. cheers lads!

[Marmoot]

Hondas have extremely quiet engines which make small noises sound bad.

Honda cars, maybe.

For Fireblades, cam chain rattle and clutch rattle are common.
Nothing to be worried about with clutch rattle if it is still sensible (best compare with other Fireblades).
But with cam chain rattle, it may be a sign your cam chain tensioner is on the way out. Common problem, and luckily not too expensive.

[CHAPLIN]

Last rattle fixed on my cbr900 was the oil pump drive chain

[Spanner Man]

A qiuck tip to test tensioner. Undo the bolt on the back of the tensioner, remove the spring careful not to loose the metal pin inside the spring and put a screwdriver in through the hole, apply some light pressure and see if you hear a click. This would be the ratchet mechanism on the tensioner moving out to the next position.

Tensioners usually fail because they dont have the spring tension to push the ratchet mechanism all the way out or the ratchet get stuck orthe ratchet wont hold its position. If this works go for a ride and see if the noise is gone. if it cures it you know that the noise is coming from the cam chain and replade the tensioner (and chian if nessesary). If the noise is still there there's a good chance that the noise is coming from somewhere else.

This is not a permanent fix as its qiute easy to over tension the cam chain using this method if you are not carefull. However it shouldn't be a problem if you just use it for diagnosis purposes.

If the noise doesn't go away it could still be the tensioner if the ratchet mechanism is not holding in its extended position. The only way to check this is to remove the tensioner completley and inspect the teeth on the ratchet mechanism. Although you will have to be sure the cam timing doesn't jump when removeing the tensioner Thats when the above test comes in handy. Quick to do and doesnt require to much in depth work to confirm a suspicion.

Hope this proves helpfull.

[CHAPLIN]

They dont have a ratchet, they have oneway taperd slides.You could try getting a m6 x30mm bolt and screw it into the back of the tensioner untill it touches the pushrod with very light pressure.Be carefull not to over tension it though, then lock it in position with a nut.I used this quick fix on my tensioner.

[Spanner Man]

Yea chaplain you are probably right there it's been a whilse since i have done one and i might have it confused. Good tip about the bolt! Should work similar to the old manual tensioners that are popular amoung the racing communitys because there is less likleyhood of them failing. But as you say be careful not to over tension. Good Advise!