problem with brake judder
 

hi all,i have a 2001 748s,i have had it from new and done 15000 mile on it,many of them trouble free,i went out on it a few weeks ago to find the front brake judded when stopping(worst from around 70mph) i thought it was just glazing ihave covered 800 miles since first sighns of this problem,would i be right in thinking disks are warped if so what other signs should i look for,im going on a biking holiday in 3 weeks so i better act quickly,if it is the disks what would be a good replacement (wave,pfm,original equipment or can you get them skimmed/straitend),other disks look ok but i like the goldy bits in the middle so if you can just buy the outer bits then great!!!!
many thanks in anticipation
:o:o:o

If the discs are warped you would get a "pulsing" felt through the brake lever when you apply the brakes.
Have you taken your calipers off & checked them & the pads?
Also a way to check your discs is to get the front up on a paddock stand, take off your calipers & tie them out of the way & spin your front wheel, you should be able to see if yor discs are warped.
Another thing to look at is your wheel bearings.


Chris.

thanks chris will check tomorrow and post back,
thanks weeksy its juddering the whole front end but you dont feel it in the lever,at 30 you dont feel it at all,i have had the suspension tinkered with but only stiffend everything one click so i will put back to factory settings,is it easy enough to strip the calipers and copper grease the pistons as i have always had italia do my work on the bike but i bet theres a 2month waiting list at least,i will probably go and introduce myself to cornerspeed after reading everybody great reveiws about him.
thanks
martin

Have to say, I don't think it's the discs either. I had a bent disc on my blade, the runout was almost un-measurable but could seriously feel it in the lever!

I'd be inclined to say loose bearings.... either wheel or steering head - I've had the brakes juddering when my head bearings were a little slack but that's something easily detected by holding the brake and rocking the bike back and forth.

thanks all for your input,ive just taken pads out and sanded them down and put them back in(pads are brembo)and for the first 15minutes there was no judder,im going to try new pads,carbon lorraine sbk3 from hien gerrick there open tomorrow will let you know how i get on

Hi Martin,
I do not recomend the use of copper grease on the brake pistons as it is an abrasive, great for stopping nuts & bolts from ceasing up & also acts as a thread lock i believe, I am sure Nelly will correct me;)


Chris.:roll:

Coppagrease can rot the rubber seals on the pistons best to use rubber lubricant or just use brake cleaner and leave them alone and just clean them more often

just changed pads for new sbk3 pads been out on it and no difference it still judders,tryd pulling clutch lever in and coasting so theres no pulse from the engine and then tryd brake lever it does not pulse the lever but i have noticed that even without braking there is a judder as if the tire isnt balanced,now i left my bike on a rear paddock stand and it makes me wonder if it has mishaped the tyre and when u brake it emphasis it,thought it may be wheel bearings but the wheel when u try to shake it seems solid so not bearings, i just hope its the tyre,try that next.

Take the front wheel out & check the bearings that way, while it is out take it to a tyre place & check the balanciing, you may have lost a weight.

Chris.:roll:

thanks chris il give that ago
cheers
martin