Brake vibration after 2k...wtf??

[team_penetrator]

Hi,
Changed my front discs and pads for Greenstuff pads and OE spec Brembo discs back in April. Since then Ive only done around 2k miles (I use the bike for the commute) and now have a random problem..

For the last few weeks Ive been thinking that brake performance has dropped. Wasnt sure if it was me going mad or not. Also detected a slight vibration throught the pedal when it was first applied at speed. Again, it was so slight that I thought it was me.

Did some motorway miles at the weekend and the vibration has now got really noticeable when the pedal is first applied at speed.

I would think it would be wraped discs, but surely not after 2k of gentle miles??? Maybe corrosion, but the outside of the disc looks fine...

Anyone got any ideas or suggestions? Ill take the wheels off and have a look at the weekend, but would be interested to see if anyone has any ideas before I do??

Thanks,
Phil.

 

[Inferno]

Vibration usually means a warped disk, although it can sometimes be caused by loose wheel bearings, a bent axle shaft or loose brake parts.

 

[team_penetrator]

If it was loose wheel bearings, Id expect a noise? I dont think anything has got bent, as I havent hit anything or kerbed a wheel...

What would cause a warped disc at such low miles and with such light use??

 

[dangerous dave]

if theres any cr@p behind the disk where it meets the hub its only a matter of time before you get some vibration.. you can use a run out tool and set to zero and see what the disk is doing, 0-4 i'd say is average on a disk with a few k on it.. anything like 10+ and its going in the bin...

make sure you set the tool up right tho or theres little point doing it at all.. it'll also tell you if you have a warped disk, warped hubs aren't uncommen, seen a few 350z's with major vibration issues due to hubs..

 

[Chris_H]

dangerous dave has got it nailed

however take the disc off and then clean the hub up and remount it. The disc will be fine, it won't have worn funny unless the 2k miles have been slowing from 200mph with a 10 ton trailer.

Also run out tool, a pencil is good enough for the common man who won't buy a DTI for 1 time use

 

[Cupster]

I used to get a bit of vibe and I have greenstuff pads. Check that one of your caliper sliders has not seized on you. This happened to me and I obviously saw a loss in brake power.

Had to buy another caliper carrier as I could not free the seized slider. Anyway I copper greased all the sliders on both calipers and normal brake power has now returned with out the vibrations.

Still get some at high speed slowing but this is probably due to my drilled discs.

 

[Riley!]

either warped disc or possibly even wheel bearing

 

[team_penetrator]

I used to get a bit of vibe and I have greenstuff pads. Check that one of your caliper sliders has not seized on you. This happened to me and I obviously saw a loss in brake power.

Had to buy another caliper carrier as I could not free the seized slider. Anyway I copper greased all the sliders on both calipers and normal brake power has now returned with out the vibrations.

Still get some at high speed slowing but this is probably due to my drilled discs.

Daft question... Which bit is the calliper slider??

 

[team_penetrator]

dangerous dave has got it nailed

however take the disc off and then clean the hub up and remount it. The disc will be fine, it won't have worn funny unless the 2k miles have been slowing from 200mph with a 10 ton trailer.

Also run out tool, a pencil is good enough for the common man who won't buy a DTI for 1 time use

Think I need some education here... How would I use the pencil technique (as it shall be known from this point forward)?

 

[Cupster]

Daft question... Which bit is the calliper slider??

There are two parts to the assembly, you have the caliper carrier which is rigid and holds the caliper itself and pads in place. The sliders are at either end of the carrier. they are what the caliper 'slides' in and out on when you press the brake.

Not the best explanation but I dont have any pics.

 

[Cupster]

double post wtf!