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Discussion Starter #1 (Edited)
Have any of you had any issues with pulsating (front) brakes? Both me and a friend of mine got this after approx. 10.000 km on our RS's. I'm thinking the rotors/disks have "deformed" slightly thus creating this effect.

None of us do track-days, but we might be riding "harder" than the average Joe...but that should not matter much. (This bike is made for the track!) With a fairly new bike, the rotors should last longer than this.

I'm looking out there to find more people that have this issue, so I can claim it under warranty.
The local shop dismissed it, as brake-rotors are "consumables" (don't know the proper English word for this), but we will fight this.



-Stig
 

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Disks should last longer than that unless you’re riding hard. You should be able to check the runout of the disk with a dial gauge or a steel rule.
One other possibility is that the steering head bearings need adjustment.
 

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Tell us more about the pulsating. Does it happen under light braking and increase with harder braking? The opposite of that? Does vehicle speed or road surface make a difference?

One trick to try: Aggressively clean the discs with emory cloth and steel wool then rubbing alcohol. Some say the brake pads leave deposits on the discs that can cause pulsing.
 

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Pretty sure Ali-bear is correct.
Bedding the brakes in and normal riding deposits an even layer of
brake pad material on the discs. So stopping power is due to friction of pads on pad material, not pads on rotor steel like everybody since the beginning of time assumed.
One cause of "uneven" pad material distribution is riding hard, braking hard to get the brakes really hot, then stopping and holding the brake lever on. This keeps hot pads against a hot static rotor thus depositing a large chunk of pad material in that spot. You might be able to use Scotch Brite pads, steel wool, or sandpaper to carefully scrub the entire rotor surface (both sides). Then bed the brakes in the normal way.
 

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Discussion Starter #6
I have heard this theory before, but wouldn't this residue be removed when braking?
If it is possible to remove this with "Scotch Brite pads and steel wool" why wouldn't the (tremedous) force of braking also remove this residue?

Has any of you actually experienced this? ...and "polished" the disks/rotors with success?

Which leads me back to my original question: anyone else having this issue?
 

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Discussion Starter #7 (Edited)
I asked the shop to measure the disks, when they serviced the bike. Just picked it up, and this is the values they measured:
Front right: 0.15mm
Front left: 0.10mm

So the disks are slightly deformed, but these values are within the tolerances set by Triumph.
 

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If that doesn't do it scrub the pads with a ScotchBrite pad and brake cleaner and then a change of pads.
I've had this going on with Buells in the past and now with an 04 Sprint.
Time for me to bite the bullet and buy a fresh set of pads.
 

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Something else to check is if You are running semi floating rotors, is the bobbins. On two pairs of rotors i have experienced sticking, causing what feels like warped rotors. In case this isn't obvious, (as it wasn’t to me)- grab the rotor and (in gear) try moving it front to back. Provided its semi floating it should have a little bit of low resistance play. A little penetrating lubricant and some love taps resolved my issue.
 

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That is a GREAT idea.
This bike sat outside for quite some time before I got it so some penetrating oil and a few smacks on each bobbin with a plastic mallet and rocked the calipers back and forth and we'll see.
I'll find out tomorrow how it works when it's back to work.

I cleaned the rotors and they're not warped and cleaned and lubed the caliper pistons and pad securing pins and the pads are clean Ferodos but as I come right to a stop they pulse.
 

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Lubing and jarring the buttons and wiggling the rotors helped quite a bit but not completely.
Looks like new pads will be going in after all.
 

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I went through this a couple years ago with my Duke 690. Single disc up front. I tried everything including the bobbin trick without success. I ended up replacing the rotor, problem solved but at a nasty expense.
 

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Discussion Starter #15
Tell us more about the pulsating. Does it happen under light braking and increase with harder braking? The opposite of that? Does vehicle speed or road surface make a difference?
When going fast and braking HARD, it is very noticable. Not so noticable when going slower or braking less hard.


My friend got his rotors changed under warranty, but my bike is out of warranty by a few months. His front tire is also ****ed up because of this. My front tire isn't completly ****ed, but I can feel that is not as "smooth" as it is supposed to be.

I bought new rotors and just changed them today.
 

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Oh. Sometimes, manufacturers will extend a warranty for good faith, if the problem is known to be a commonly occurring issue. But, thinking about some of the posts I read here about how Triumph NA operates, getting new rotors yourself was probably the wise choice. Make sure you bed the new rotors and pads correctly
 

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Discussion Starter #17 (Edited)
Oh. Sometimes, manufacturers will extend a warranty for good faith, if the problem is known to be a commonly occurring issue. But, thinking about some of the posts I read here about how Triumph NA operates, getting new rotors yourself was probably the wise choice. Make sure you bed the new rotors and pads correctly
I tried getting mine under warranty, but Triumph refused.

Now it's like I'm riding a new bike! The difference is massive.
 
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