Hello
I just noticed that when I come to a stop at slow speed the brakes are "pulsing" like the rotor might be warped, however at any other speed say over 20 mph up to 100 plus, the brake feels solid with no pulsating feeling whatsoever, so to speak.
So if the rotors were warped wouldn't it pulsate at any speed? Why only at slow speed when I come to a stop light?
Also I have no feed back of any kind to the brake lever just a "pumping " motion of the forks as I come to a stop.
Pads look in good shape as well as the rotors from a visual inspection.
Should I replace pads first see if it cures it or replace rotors?
Any idea?
Thanks for the help.

* Last updated by: doomking on 9/19/2017 @ 9:56 PM *

It's possible your rotor buttons are gunked up with brake dust and road grime. Remove the rotors, lay them flat and put a drop of penetrating oil where each button contacts the carriers and the rotors themselves. Let the rotors lay flat over night and the next day, fashion a tapered hardwood dowel that you can jam into each button in turn and attempt to rotate them in place. Once you get them all freed up and rotating, degrease and wash thoroughly. After they're dry, mount them to the wheel, the wheel back on the bike and see if you did any good with the low-speed pulsing.

Thanks for the response.
So for what I understand those round buttons have to spin freely in order for the rotor
to perform correctly. Should I try to rotated them before I remove the rotor just to see if they are freezed up?
Thanks for the help.

The buttons don't have to spin but they should float freely. They allow the rotor to center in the calipers. If some are frozen they could be holding the rotor slightly out of true.

Mad

I tried to move the buttons around with my finger and they all seemed completely stuck with no play whatsoever.
I am a bit confused about those ring buttons since I can’t seem to find any play at all and here you say it should float freely..

They're going to have an amount of friction just sitting there.When the wheels starts turning,they move some...spinning by hand probably won't give you what you're expecting.Long as they're 'moveable' then they should be fine.Spraying and cleaning is good advice.The move mostly when the pads are applied.Spray as suggested,and tap each one lightly with mallet or light hammer.Respray and clean off residue.I would say leave em on the wheel. Each does things how they want.

* Last updated by: Grn14 on 9/20/2017 @ 6:28 PM *

Do something like this... walk the bike a few yards so it rotates the pistons back into the caliper.
Does the brake lever move where you have to pump it back up? No... then don't worry about it.
Does the brake lever need pumping up before it has a good hard pedal? Yes... then the discs are going bad.

The power of compressing the lever that hard at those higher speeds shows it not as bad as you think. It has to whaa-whaa your hand like you feel when it's braking at slow speeds.

bad rotor or bad rim

You probably won't be able to spin the buttons by hand in any case. These are "semi-floating" rotors, not "full-floating. But they must be free to move and not frozen in place. ZX-14 rotors are not the most durable and I know quite a few people who've warped theirs. Cleaning the buttons is a lot cheaper than replacement and can sometimes restore lost smoothness.

Hmmmm... interesting advice. Mine does exactly the same thing.

Knowing the problems I had on an 08 Concours, I chalk it up to poorly designed OEM rotors. I just put up with it until I decide (read "can afford") to replace them with some aftermarket rotors and pads.

I will try cleaning those buttons connecting the rotor to the bracket. I never heard of that before.

My think goes something like this:
1. Heat treat disc = pass-fail test.
2. Disc is on a production run = in the thousands.
3. Rider A never has a problem with dis warp throughout the life of the bike.
4. Rider B has a unique braking habit and warpshit outta the discs.

I think it is uneven pad transference mostly caused by simply
braking to easy/softly for to long.

Cleaning buttons wont do anything. (wives tale/urban myth)

If you really think your rotors are warped then measure run out
on rotors and make sure they are within service limit.

Go do some stoppies (hard enough to get back tire off ground) and
some high speed hard stops from triple digits for a day and get some
heat/wear into the rotors and you will be fine.

Or..... just spend a bunch of money and buy new set of rotors and pads.

Or.. send rotors to Truedisk resurface and new set of pads.

Stoppies most fun and cheapest.

I agree.

We discussed "pulsing during braking" years ago. My '07 started "pulsing" and I swore it had to be a bad rotor. But it made no sense to me because I don't brake hard and the rotors showed no sign of odd wear and spun freely with the wheel up.
A few members suggested the tire could be the issue. If it makes sense or not, I replaced the original Bridgestone which had about 1/2 it's tread remaining, with a Michelin Road Pilot 2 and the pulsing was completely gone.
I can't explain why but my bike pulsed at about 70 mph with light brake applied and at any speed below 25 mph. At all other speeds and conditions there was no noticeable pulsing.
So think about the tire before buying rotors.

As your tires wear they begin cupping. All tires experience cupping, but it's a matter of degree. If you're suspensions in good tune/condition, you may not even be able to see cupping in your tire even fully worn. It's not abnormal to experience some cupping. If you go out on a track with brand new tires they are severely cupped after a ride, this is indicative of bad tuning (or outright broken suspension). If over the length of a tires live, at the end you see some low spots and cupping patterns not a big deal. You might be able to do something. Basically think about it as if when the tire is worn out, it's worn out so who gives a shit? If it's so badlly cupped at 50% tread level it needs replaced it probably means you have poorly tuned suspension or even broken suspension.

Keep in mind riding conditions also affect this. But if you know riders who ride in your same areas and under the same conditions and their tires don't (or maybe do) the opposite of yours it may indicate you have something needing looked into.

Pulsing can also occur not from only warp but slippage. A rotor may develop hard spots or what not that do not allow the pads to grip as much as they would on normal surface.