VFR800 Brake grab

I'm having a brake grab prob with the front brakes on my "99 VFR800. It is not noticable at high speed, but at low speed and coming to a full stop it is most pronounced. There is no pulsing through the brake lever, but it feels like the brakes ar grab at a specific spot on the disc. I've checked for contaminants, inspected the calipers and replaced the pads. The bike has actually done this very slightly since new, but lately it's become much worse. I don't have the tools to see if the front wheel is out of true. Any ideas?

 

I'd mic or even try a vernier caliper and check thickness all the way around each rotor if there's nothing visable. Maybe a thick spot, I've seen it on cars but never had it on a bike yet.

 

Make sure the slider pins are well lubed and move freely.

Possibly warped or bent disc.

 

You may also want to check that the lever is not hanging up or sticking. Doodle had a problem like this last year and the lever was just touching the piston and made for an abrupt brake when hot or grabbed in succesion.

 

Thanks for the suggestions guys. I decided to try seriously cleaning the brake discs again. I cleaned them with kerosene, then scrubbed them with a stiff brush and detergent, then dried them off and used a light emery cloth. Result: perfect. I guess I should have cleaned them properly in the first place. Doh!

 

Huh, I am having the same problem and was looking for a thread on replacement disc suggestions because I figured it was just a warped disc. Thought that was weird for something so light to warp a disc, but figured if it happens on a car, guess it could happen on bikes. Thankfully, I found this post instead. I will give cleaning a shot. How stiff of a bursh did you use? Like a stiff house cleaner type brush, or stiff as in wire brush? I've never used emery cloth before either. What is the difference between emery cloth and sandpaper?