Frame judder with rear braking

[summerdays]

My disk brakes I have to admit are not necessarily the quietest in the world ... but yesterday I was experiencing a lot of frame vibrations with using the rear brake (Juicy 3's), but as I was really wet I didn't investigate. I noticed today its still quite bad. I can get the whole frame to judder if I pull on the rear brake and push the bike forwards even gently, whereas the reverse with the front brake just causes the wheel to lock and slide along the ground.

Other possible contributory factors ... I fell off - low speed on muddy road last week, and I had a new rear tyre about a month ago.

I've had a quick look ... I assume something has to be loose or broken to produce those vibrations ... is there anything I should look for ... though I'm tempted to just go to the LBS later this morning (but I would need to clean the bike first ).

 

[02GF74]

possible causes:

you replaced rear tyre so is the skewer securing the wheel done up propery? check wheel is not loose in frame
is the disc warped/bent/damaged?
spokes loose in wheel?
caliper bolts not looosened

kinda hard to say without seeing it.

 

[marzjennings]

Yea, I'd guess a warped disc. You may have knocked it when you fell. But, as mentioned, it could be a number of things.

 

[PaulSecteur]

Possibly a contaminated disk or pad?

Halfords do a can os disk cleaner for about a £5, worth a go just to rule it out.

 

[e-rider]

Possibly a contaminated disk or pad?

Halfords do a can os disk cleaner for about a £5, worth a go just to rule it out.

or you could just buy methylated spirit directly for 99p!!!

Don't use white spirit though - leave a slimey residue behind - not good for brakes!

 

[summerdays]

I did clean the disk brakes (with a Muc Off product) at the same time and it seemed to fix it in the very short term (riding up and down the road by my house)... next day it rained and it seemed almost as bad. So I'm intending on looking at the pads at some point over the week end to check they aren't worn out (well to be precise I'm intending that Mr Summerdays is going to look for me but its been too gloomy today to want to be out inspecting the bike. And checking that the wheel is seated properly etc.

But the bike did need that clean... found lots of bits of leaves in the cogs.... as well as the obvious ones on the frame.

 

[2Loose]

I had the same issue once with my old M0 Summerdays. Bad frame judder, far more noticeable when it was wet.
Turned out to be the rear wheel slightly out of alignment, loosen the wheel and reseat it and then do the calipers.

 

[summerdays]

I had the same issue once with my old M0 Summerdays. Bad frame judder, far more noticeable when it was wet.
Turned out to be the rear wheel slightly out of alignment, loosen the wheel and reseat it and then do the calipers.

Well we have done that today ... we will see how it is tomorrow ...

Mr Summerdays seems to think I'm locking the wheel up ... so perhaps it does relate to my new tyre and the way it meets the surface. Its got to the point where I'm thinking about it too much that I'm not braking normally ...

 

[potsy]

Do you use both brakes fairly evenly S'days?
I tend to only use front one 90% of the time and only bother with the rear one when I really need to stop in a hurry.

 

[summerdays]

I normally use both brakes ... I thought fairly evenly ...today I know that I was only using the back brake as I was testing it... trying to see if it would shudder to demonstrate my problem to Mr SD. I didn't go any distance ... just up and down the road outside the house.