2011 high speed brake Judder!

[007neil]

hi all, new to this forum.

i have a 2011 s1000rr which i race, and i have been experiencing some pretty significant brake judder while braking hard at the end of some long straights. i have changed the stock pads to SBS pads and i have checked the discs which are straight. i have also changed to brake fluid. any ideas would be helpful?
cheers
neil

 

[rusty]

Welcome, sure somebody will have some ideas for you.

 

[Billy]

Head stock bearings or deposits on the calipers ??

Billy

 

[Billy]

Head stock bearings or deposits on the calipers ??

Billy

I meant to say deposits on the discs

 

[Alien6872]

Just had my first annual service and the technician found that the head stock bearings needed tightening, so might be something worth checking?

 

[andybarsblade]

What discs are you using?

 

[Burner]

Could be the pads? I did a track day at Silverstone and had brake judder so bad at the end of hanger straight that it was buzzing the brake reservoir backwards and forwards +-10mm. The pads that were fitted were 2nd hand ones I bought at the track as they were running a BMW day at the time and I was desperate for some spares. This was after the OE ones had worn out, which I only noticed when sat in pit lane waiting to go out and clocked the brake fluid was low. The bike had only covered 850 miles at the time so I wasn't expecting them to be shagged quite so soon. Changed the pads to new bendix ones and problem went away.

 

[lllN30lll]

Mine does the same, but I think I've got a warped galfer.

 

[007neil]

stock discs.

 

[lllN30lll]

mines does it braking after anything above 70mph.

 

[007neil]

it started just as the stock pads where worn down. so i replaced them with sbs sinter, (which i had always used in my Cbr1000rr) it sort of went away a bit but then came back with vengeance at the next race.
i will check the head stock bearings, i have already cleaned the discs up with emery cloth after i fitted the sbs pads... i had read on an american forum that its the pads, so i have ordered some brembo Z04 race pads to try.. i have never had this on any of my race bikes and its frustrating because i have no way of testing it until morning practice of race day... :upset:

 

[rusty]

Also check the pinch bolts on the forks, they 'apparently' come loose and may even fall out !!!
This will cause severe juddering at lower speeds, and is rectified by tightening and replacing said bolts.

 

[007neil]

thanks for the advice, but i always use a torque wrench to torque up all the nuts and bolts.

 

[rusty]

thanks for the advice, but i always use a torque wrench to torque up all the nuts and bolts.

That's what I always believed, until I checked yesterday. Judder problem removed.

 

[lllN30lll]

Also check the pinch bolts on the forks, they 'apparently' come loose and may even fall out !!!
This will cause severe juddering at lower speeds, and is rectified by tightening and replacing said bolts.

Only happens at higher speeds though

 

[rusty]

Only happens at higher speeds though

Nope lower speed for me.

 

[007neil]

yes only at high speeds at the end of straights, i'm going to try some EBC brake pads

 

[timmo]

i have some judder at low speed ,i can move my discs about a mm in a radial direction ,like turning a steering wheel,
both sides ,surely thats not right ?

 

[rusty]

i have some judder at low speed ,i can move my discs about a mm in a radial direction ,like turning a steering wheel,
both sides ,surely thats not right ?

Fortunately your discs float, as they are supposed to.

 

[Lumpy]

I get a little judder when i really throw the anchors out, high and low, I just thought it was the ABS kicking in. Although sometimes when it has happened at low speed i did sort of think! that can't be the abs....