unusual front end noise + chain slapping

[Damz]

Hi recently when iv'e been riding my bike i have begun to notice an unusual sound which appears to be coming from the front. I can only here it when doing above 20mph and have the clutch pulled in and kind of rolling, its still there when applying both brakes so dont think its a brake problem.

the sound is somewhat like a steam engine, chuffing that is faster when the bike is going fast and slows down with the bike until its not noticible.

iv'e had a very badly worn wheel bearing on the front but sounds different as that was more of a knocking sound.


now onto the chain noise, regardless of how tight the chain is it still slaps the underside of the swingarm whenever i go over a bump, is this normal?? and when i roll the bike backwards down my driveway it makes a kinda creaking sounds from as its moving, i suspect its from the chain or sprockets but since im on the bike above it it is quite difficult to tell where it is coming from.

the chain and sprockets were changed last august iirc and the front wheel bearing was done a year ago, could either of these have worn out that quickly?

one more thing, when the bike is warmed up or near the end of the temp gauge it is really loud, i know the ticking sound is normal but should engine noise increase that much when hot?

[challymo]

Hi recently when iv'e been riding my bike i have begun to notice an unusual sound which appears to be coming from the front. I can only here it when doing above 20mph and have the clutch pulled in and kind of rolling, its still there when applying both brakes so dont think its a brake problem.

This could very well be a slightly warped disc, or if its the same as what I had an off centre mudguard. Just check both these things (may be something else but not that I can think of)

and when i roll the bike backwards down my driveway it makes a kinda creaking sounds from as its moving, i suspect its from the chain or sprockets but since im on the bike above it it is quite difficult to tell where it is coming from.

I had something similar to this but it turned out to be an old rear shock that needed servicing/replacing.

[castrol101]

Are you running standard sprockets? Sometimes a poor choice of sprockets can casuse the chain to hit the swingarm.....

As for the chugging steam engine sound i had that too, as challymo said i believe it was a very slightly warped disc, even though it felt fine through the lever. It never really bothered me so i left it lol.

[Damz]

its doubtful its the front mudguard as it currently doesnt have one as the previous owner had tightened the bolts for it too tight and cracked the connecting parts so had to remove it the other day.

what would be the best way to check if its a warped disc? the brakes seem ok, not great atm, going to overhaul them for a trackday im doing soon anyway.

also it is on standard sprockects as far as im aware, a friend suggested the rear shock might be getting old as when he was following me he said i bounced quite a bit. again how would i check this?

[challymo]

With the front disc, ride along and apply the front brake gently if you can feel pulsing through the lever that would indicate a warped disc. If not get something you know to be straight and put it against it and see if it sits flush across it. (i'm sure theres a more technical way but i can't think of one atm) As for the rear shock try sitting still and bouncing down on the rear and see if it squeeks then and how quickly it bounces back. To be honest though they are quite old bikes now so it could do with a service most likely.

[Phil Norton]

I'd look at getting the chain sorted first, as this may the the route of the noise.

It's obviously at the end of it's life if it's slapping on the swingarm. Does it have tight and loose spots on it when you adjust it? It could be caused by a tight link going round the front sprocket and creating a lot of noise. My R1 suffered a similar problem last year.

[Neosophist]

Sounds like a worn chain is one of your problems...

have you tried checking the front wheel bearings? lift the wheel up and see if you can rock it... I had an old honda xbr that made the same kinda noise.. had a broken bearing in the front.

[Damz]

i have discovered the cause for the front end noise this afternoon, its a sticky caliper and the brakes are dragging.

when me and a friend were drilling holes in the new mudguard and fitting it we decided to take a gd look at the wheel, lifted the front wheel off the ground and it was hard to move so pushed the pads back and the wheel spun fine afterwards so we had found the cause.


now to fixing the problem. how should i go about this? iv'e been working on my fzr250's brakes recently so used the same techniques. bassically i took out the pads, removed the caliper and placed a wrench in the gap and pressed the brakes until the pistons came out and gave them a gd soaking in wd40 and gave them a gd wipe and were nice and shiny...... however the top of the piston is impossible to clean and the gap between the piston and caliper is tiny, any ideas how to clean it? would i have to split the caliper to get at it?.

i also came across a problem, after i cleaned one of the pistons and pushed it back in, it forced another piston out, i got it back in fine and bled the brakes afterwards and they are working but not as well as before, how much bleeding of the system will i have to do? there doesnt seem to be anymore air coming out but the brakes still feel rather spongey.

anyway i took the bike for a ride after cleaning most of the pistons ( still that wee bit at the top i cant reach) and still getting the brakes to drag, any tips on how to stop the brakes from dragging? and for cleaning the pistons?.

the chain i suspect is just loose and will tighten it up when i get the chance, its still got plenty of life on the marker and only put on a few 1000 miles ago.

[Aether]

Hi Damz,

I'm having the exact same problem, my left caliper drags and gets really hot. So far I've stripped the calipers and cleaned them, rubber-greased them and re-bled the system, but it's still dragging really badly, so I rolled the bike along with the mounting bolts finger-tight and applied the brakes a few times, I believe this helps them sit right? A bit better, so then tried loosening off the axle & pinch nuts which didn't make any difference... I think it moves a little better if I mess with the span adjuster? I'm out of ideas now!
When I bled the system I sucked the fluid through the bleed valve with a syringe and then bled as usual. I tap the M/c, calipers etc to get any bubbles out and loosen off the banjo bolts at the M/c end too, then tied the lever on overnight. Seems to work pretty well for me (apart from my dragging caliper!).

[Damz]

going to be leaving the bike as it is as theres no point trying to fix the brakes when im going to be fitting in self bleeding nipples, braided lines and new fluid in a few days.