tapping sound when braking

[HarryHornby]

When I use the front brake I get an audible tap/knock coming up from the front wheel.  It happens once per squeeze of the brake lever.  so if I quickly apply the brakes say 10 times in 5 seconds I get 10  taps.  I can't get it to do it when stationary and applying the brakes.  Presume it happens at high speed too but can't hear it for wind noise obviously.


I did give the front wheel a tug the other day and there doesn't seem to be any bearing movement.


The bike had new pads about 18 months ago, but it's only recently that I've noticed it.


Any common problems that people know about?


cheers

[BBROWN1664]

check the pads and pins. Sounds like it could be movement of the pads as you apply the brakes.

[darrsi]

Either pad movement, or outer disc movement.

[HarryHornby]

sorry, thick question coming, what's the outer disk?

[BBROWN1664]

the big shiny metal thing that the pads grip rather that the rotor bit that is bolted to the wheel.

[Grayo]

When I use the front brake I get an audible tap/knock coming up from the front wheel.

I had exactly the same knocking from the front end back last year. Took it to my local Yamaha dealer and it turned out to be worn front calipers. The brake pads were moving in the calipers under braking. The dealer advised me to look for a decent second hand set rather than buy new ones (extortionate price) and they would fit them for me. Managed to get hold of a near perfect set of second hand ones on ebay for £150. Problem solved.

[HarryHornby]

Cheers BBBrown, I assumed the disk was the disk.  I now get rota and disk 


will take callipers off this weekend and take a look, ta muchly, sounds fairly easy to fix (famous last words).  Just needs Red98 to tell me it's an easy job and all will be "fine!  :rolleyes

[darrsi]

Fronts are semi floating, as in 2 parts but fixed into position by rivets.
You can get fully floating ones that make a really fucking annoying jangling noise all the time and appear to be loose.
The rear is just a fixed disc/rotor.
It's all about heat dissipation and heat expansion, which is why so many people have so much grief with the rear disc, because it can get quite hot and it transfers the heat through the bolts to the wheel hub, causing the 2 different metals to fuse together.

[Punkstig]

Sit in front of the bike and have someone else apply the brake at different pressures whilst you try to move the wheel, you'll have a better sound of the noise and should be able to locate it, it's more likely the pads are moving slightly in the caliper but there could be other reasons that you'll be able to diagnose.

[darrsi]

Sit in front of the bike and have someone else apply the brake at different pressures whilst you try to move the wheel, you'll have a better sound of the noise and should be able to locate it, it's more likely the pads are moving slightly in the caliper but there could be other reasons that you'll be able to diagnose.

Or just get them to hold the brake and rock the bike to and fro.  :guitar

[stevie-g1968]

Its dirty bobbins/rivetts on the disc's. Give them a good clean withe brake cleaner and a brush... a good old poke n scrub, they block up with brake dust and road grime.

[HarryHornby]

Your idea made perfect sense, Adam, but I couldn't spin the wheel fast enough because when I touched the brakes it just stopped dead with no tapping, bugger.


But, on the plus side, the missus did look rather fit hanging over the back of the saddle to keep the front wheel in the air.  :b

[darrsi]

Your idea made perfect sense, Adam, but I couldn't spin the wheel fast enough because when I touched the brakes it just stopped dead with no tapping, bugger.


But, on the plus side, the missus did look rather fit hanging over the back of the saddle to keep the front wheel in the air.  :b

Gently apply the brake then try and rock the wheel to and fro by hand with the wheel off the ground, or do the same by rocking the bike to and fro on the ground whilst listening out for the noise.

[Punkstig]

Ok, so here's another one bud- my brake discs became contaminated from a fork oil leak (the lower bolt that holds the internals had loosened and dumped the oil)
After cleaning and replacing the necessary I had a pretty loud knock from the front somewhere when applying brakes but only when coming to a complete stop, took me a little investigating holding the brake and bouncing the front end to realise the the front wheel was slipping under braking and the noise was the disc moving through the caliper as the pads had soaked up the fork oil (I had scrubbed them clean) replacing the pads and properly cleaning the discs cured my problem but until I realised what it was I thought it was noise coming from the forks binding!

[HarryHornby]

I've got an idea Mr Stigg, we could have a little competition during the LOFO ride out on Sunday, what's up with Harry's brakes, winner get's a cuppa!  :-)  Fixer gets a breakfast! 


PS it's not when I stop, it's every time I use the front brake.

[Punkstig]

You do realise what you've just offered to everyone right!?

[HarryHornby]

EVERYONE???? errr hang on do I need to change the rules???  LOL

[BBROWN1664]

:agree with Punkstig

I was going to reply earlier but thought you might get upset when you realised you were offering your Mrs for breakfast :pokefun

[HarryHornby]

nope you've lost me lads, there is obviously some slang somewhere I've used but I know not what.  :o


Oh, and an update.  I can make it tap when pushing the bike and applying brakes.  I got the missus (who's apparently now offered as a prize to the LOFOs) to get down at ground level and have a listen each side but I was greated with a vague look and "I can hear it but no idea".

[bandit]

Harry,do the pads have any up & down movement in the callipers with brake off.