Judder issue

[markc663]

Evening all,
I'm hoping one of you guys can help me out with a problem, or maybe anyone experienced the same problem.

My bike has started to suffer from juddering on the front when braking. The harder the braking, higher the speed the more severe it becomes. Becomes more noticeable when the bike is warm. On Saturday I replaced the brake pads with oem pads (as were previously fitted), pumped out the pistons and cleaned all around them with brake cleaner and a toothbrush. On each caliper I had to block two pistons off to get the others to pump out, cleaned all and pushed back.
Built up, took for a run for 20-30 miles, all seemed ok. Went out on a run on Sunday and the problem re occurred once up to temp.
I'm going to see CheekyKev this week to see if he can help me in any way, just wondered if you lads had any suggestions being SP owners.

A bit about the bike. 2001 SP1, 11.5k miles. Owned since July when it had 7.8k on it. Going through the paperwork it had been stood for 4 years prior to me buying but I have put quite a few trouble free miles on it since. Fluids were changed August last year.

Any info on the same problems or suggestions much appreciated. Thanks, Mark

[Peter319]

Sounds very much like warped discs to me. It can happen if you go through a puddle during a hard ride and the discs get rapidly cooled from hot. It' rare though. I've had it on a couple of bikes before.

[Wyvern971]

Other thing to check is your head bearings, as when a bit work / loose, it will give some play which gives a similar effect to warped discs

[Peter319]

Other thing to check is your head bearings, as when a bit work / loose, it will give some play which gives a similar effect to warped discs

+1

[Sppete]

May as we'll add wheel bearings to the list too. Very easy to check at the same time as the head bearings.
If you have an Abba type stand get the front end off the ground grab the bottom of the fro legs and shake them forwards and backwards violently. If you feel movement/ or clicking it s the head bearings.
If not grab the wheel top and bottom and give them a good shake too.

Pete

[The Stig]

If you brake hard and don't feel a looseness in the head bearings and don't feel slop from wobbling your front wheel when on a stand, it's likely not the bearings...
Sometimes the discs can get glazed. You could try sanding them with coarse emery paper but would need to get the discs off to do this.
Mine did actually get warped. You can buy cheap ones used, or invest in a set of better discs so it won't happen again. Brembo T-Drive or Braketech will be the most reliable, but are fairly costly. You get what you pay for with discs...

[Peter319]

If it is the discs, I sent a pair away for straightening a few years ago and they came back good. It took a while to find somewhere that did this but (if I remember correctly) it only cost £40 ish.

[pbc0]

If you brake hard and don't feel a looseness in the head bearings and don't feel slop from wobbling your front wheel when on a stand, it's likely not the bearings...
Sometimes the discs can get glazed. You could try sanding them with coarse emery paper but would need to get the discs off to do this.
Mine did actually get warped. You can buy cheap ones used, or invest in a set of better discs so it won't happen again. Brembo T-Drive or Braketech will be the most reliable, but are fairly costly. You get what you pay for with discs...

Glazed disks.
Classic if you've been running the brakes hot & parked up. You'll get a glazed spot under the pad & it'll cause exactly what you describe.
It's happened to me.
Cut through the glazing with emery & all should be well again.
Don't live with it because the discs will start to wear unevenly.
Warped discs would normally cause pulsing at the lever.

[markc663]

Thanks for your suggestions gents. Been round at cheekykevs all afternoon. He checked the wheel bearings - good, headstock - all seemed good, couldn't feel any play. Took out the new pads, pumped all pistons out and back in ok, cleaned again and put back together. Flushed fluid with fresh.
Measured the disc run out with dti gauge, left was 0.20 and right is 0.50. Honda says maximum is 0.30. Obviously the right disc is outside of this but do you guys think this is enough to cause the problem?
Tomorrow morning I'm going to try taking of one caliper and blocking it up then road test to see if the problem goes with either side brake not in use.
Still, we're going in the right direction! Thanks very much for your help so far Kev, very much appreciated.

[bushman]

It might be worthwhile to rotate the buttons on the discs,and give the seats a clean with brake cleaner,they can gum up.You can use a nut and bolt to twist them as you clean.