ST1100 front brake shudder

[North]

My front brakes on a 2001 ST1100 (non-ABS) shudder while braking at slow speeds. It almost feels like ABS is kicking in, but (a) my bike is not ABS (b) it is at low speeds when ABS should not kick in. It usually happens when coming up to a red light the last few feet. I looked around the front brake calipers and nothing seems loose.

I can post what front discs I have on the bike, if that will help. Not sure if i should be taking it in to a shop or not. I have no problems braking at high speed. I have done a few emergency braking tests after i noticed the shudder.

Thanks

 

[John OoSTerhuis]

Warped rotor? Check the runout.

 

[BuddingGeezer]

Another cause of brake vibration/judder is 'black spotting' of the rotors. Black spotting is where the rotor has developed hard spots from uneven heating and cooling of the rotor. the hard spots are slick and slip on the pads, then the pads grab the non hard spot on the rotor causing judder.

the cure for hard spots is new rotors, same as warped rotors.

 

[North]

the rotors were new aprox. 10,000 km ago. I hope they do not need to be replaced as they are expensive. I will check them tomorrow.

Thanks

 

[Firstpeke]

I would also suggest coming off the front brakes and just using the rear in the last few yards of lower speed braking..... this improves your low speed stability... also, don't hold the front brake on when stationary, use the rear whenever possible, this prevents, or reduces the incidence of, the front brakes getting warped or "spotted"..... makes for smoother braking and more stable low speed riding...

Main reasoning behind this is that when the front brakes get hot braking from speed, and they will as it's a heavy bike after all, if you keep the brakes applied after stopping, the pads retain the heat where they are holding the disc.... this causes a different cooling rate for that part of the disc and results in them warping over time.... (eggs sucked?)