Well…

My rear brake hasn’t been working well over the last few weeks… So I used some Isopropyl alcohol on the disc to clean it, loads of black stuff came off…

So I rode the bike down the street, braked and there is a huge vibration coming from the back… So huge my feet and knees felt numb while braking!

WTF is going on!?

Bike in question…

My Mountain Bike by MilkieKula, on Flickr
180mm Rear Disc, Avid Juicy 7’s..
Yes I know, ditch the Juicy’s and replace 180mm with 160mm.. 160mm will be going on tonight.. Anymore sensible options!?

BTW I’ve got to sort this for tomorrow… Going to see Jedi! 😆

…lastminute.com !

Is the caliper tight to its mount and is/are the bolts tight on the rotor?

Checked all bolts, all nice n tight.

Does it have spacers on the bolts that hold it to the frame? They are normally in pairs, one convex and one concave. On my Elixirs I have this setup and I managed to fix the vibration by changing the spacers. The spacers are exactly the same as the one on V-brak blocks.

You have left some of the deposits on the disc unevenly. sand the disc gently to get a deposit free surface and bed the pads in again

I had similar on my 456. The vibrations were awful on road but I never noticed off road as there was more vibrations/bumps from the ground. Mine were BB7’s and it went when I changed brakes to Hopes so maybe jonba has the answer up there ^^

Avid
I’ve seen this a few times, only option is to get rid and get Shimano or Hope.

Jonba, I didn’t try that, I’ll try jiggling the self levelling spacers? and re-align the disc.

I’ve got away with it, by fitting a new 180mm rear disc and bedding the pads back in… It doesn’t stop as well, but at least it doesn’t vibrate and sound like like a fog horn..

At least this gets me out of the shit for tomorrow! 😀

I will be changing my brakes for something that requires less maintenance… Hayes 9’s worked fine, why did I change them to Juicys!??