How do you tell if your rotors are warped?

[aka1004]

My spyder RS pulls to right when braking and someone presented 3 possible problems.
Alignment, bad ball joint or warped rotor.
I checked ball joint as instructed by moving front fenders forward and back but no movement of a-arms.
Alignment will have to wait although right wheel is toed out a lot visually but not really a accurate measurement.
So how do I tell if rotors are warped?
I bought the 3 year old 15 RS with 700 miles on and put 10000 miles on and it was like that from the beginning but didn’t get any worse.
Thank you in advance.

[2dogs]

If the rotor(s) are warped they will shake the front tire(s). More likely it is your left caliper that is not working like it should.

[hypurone]

If the rotor(s) are warped they will shake the front tire(s). More likely it is your left caliper that is not working like it should.

Or simply the right side is working better than the other due to differences in pad or rotor face conditions.

OP, do several (at least 5) repeated hard stops (without coming to a complete stop) on a traffic free road. Then drive around for 15mins to cool them down (again, preferably without coming to a stop). This will bed the pads in again, then reassess how it behaves... If it has been 2 years or more since the last brake fluid flush, I would highly recommend that as well. This is what can cause a difference in the caliper effectiveness 2dogs is referring to....

[bluewoo]

https://www.youtube.com/watch?v=Ra5auJ8vDpk

https://www.youtube.com/watch?v=h6qO9Y0KKuc

[trikermutha]

Caliper sticking?? Air in the line?

Just some things to add to the check list

[aka1004]

Thank you everyone. I will try suggested things.

[JFD]

If you have warped rotors the brake pedal will pulse as the pads are pushed out and in by the rotor.

[aka1004]

If you have warped rotors the brake pedal will pulse as the pads are pushed out and in by the rotor.

I don’t have that symptom. Thank you.

[BLUEKNIGHT911]

My spyder RS pulls to right when braking and someone presented 3 possible problems.
Alignment, bad ball joint or warped rotor.
I checked ball joint as instructed by moving front fenders forward and back but no movement of a-arms.
Alignment will have to wait although right wheel is toed out a lot visually but not really a accurate measurement.
So how do I tell if rotors are warped?
I bought the 3 year old 15 RS with 700 miles on and put 10000 miles on and it was like that from the beginning but didn’t get any worse.
Thank you in advance.

You remove them and put them on thick piece of glass …. then try and slide a thin piece of paper under the edge around the circumference …. if you can - se if it happens on the opposite side …. this will tell you if it 's warped ……. Mike :ohyea:

[Chupaca]

:agree: but if you leave the rotors on the spyder you would have to check the run out. Set a fixed pointer just against the rotor and turn the rotor watching that the distance rotor to pointer stays the same at all times. Don't if it was mentioned but do you have equal tire pressure...? You can start with a cleaning of the pads and rotors but I don't suspect the rotors....:dontknow:

[Wildrice]

My spyder RS pulls to right when braking and someone presented 3 possible problems.
Alignment, bad ball joint or warped rotor.
I checked ball joint as instructed by moving front fenders forward and back but no movement of a-arms.
Alignment will have to wait although right wheel is toed out a lot visually but not really a accurate measurement.
So how do I tell if rotors are warped?
I bought the 3 year old 15 RS with 700 miles on and put 10000 miles on and it was like that from the beginning but didn’t get any worse.
Thank you in advance.

Warped rotors cause a pulsing sensation in the vehicle & the majority of time you can feel the pulsation in your brake pedal, the slower you ride & brake the slower the pulsation; the faster you ride & brake the faster pulsation will be felt. That's all there is to it. Rotors can be warped by a long hard braking--long enough to heat the rotor beyond its intended operation level. Normally warping occurs if the rotors are resurfaced on a shop machine. If the pad surface falls below the minimum thickness requirement, the rotor will warp much faster than an inspect rotor. But it is possible to warp a brand new rotor if one goes from a high speed like 80-90 mph & stands on the pedal hard all the way down to a stop. different manufacturers produce different quality metal in their rotors. the low end price of the Chinese junk was a common problem.

[JKMSPYDER]

I replaced my front rotors and pads over a year ago. The symptom I noticed before I did that is that the right front wheel would shimmy quite a bit if I applied the brake hard. After changing the rotors and pads with the ones from BajaRon neither wheel shimmies no matter how hard I press the brake.

[aka1004]

I get a big dip to right, not just shimmy.
it seems like alignment is most likely as I am not getting symptoms of other faults.
I keep both tires in front at same psi

[Wildrice]

I get a big dip to right, not just shimmy.
it seems like alignment is most likely as I am not getting symptoms of other faults.
I keep both tires in front at same psi

You could have a major castor problem usually caused by a bent control arm components. Looks like you need to go thru all the motions of checking alignment & pulling the wheels & calipers off to verify you didn't drop a broken pad on the left side.
Good Luck,
Darrell

[BajaRon]

You may have already looked into this. But if your A-Arm bushings or your tie rod ends are worn, it can give you the same general symptoms as warped rotors. Have you done a run-out on your rotors yet?

[aka1004]

You may have already looked into this. But if your A-Arm bushings or your tie rod ends are worn, it can give you the same general symptoms as warped rotors. Have you done a run-out on your rotors yet?

since I don't know what you are talking about, I am gonna say no. ;)
but this something I bought last year with 700 miles.

[aka1004]

one of spyder tech said riding brake can warp rotor pretty quick, is that true?
since previous owner only put 700 miles in 3 years I have to assume he/she was not a avid rider.

[BajaRon]

since I don't know what you are talking about, I am gonna say no. ;)
but this something I bought last year with 700 miles.

Did you watch this video?
https://www.youtube.com/watch?v=Ra5auJ8vDpk

You don't have to do it this way. All you need is a way to get something very close to the rotor, stabilize it somehow and rotate the wheel. This way you can tell if the rotor is going in and out (warped). If it does go in and out more than the specified limit, then you need to replace the rotor. Until you do this, any speculation is pretty much a waste of time.


one of spyder tech said riding brake can warp rotor pretty quick, is that true?
since previous owner only put 700 miles in 3 years I have to assume he/she was not a avid rider.

Again, I know you are curious as to how a Spyder with only 700 miles on it would have the problem you are experiencing. But figuring this out isn't going to fix the problem. And until you do some targeted inspection, it's all just speculation. Which won't fix your problem either.

[Wildrice]

one of spyder tech said riding brake can warp rotor pretty quick, is that true?
since previous owner only put 700 miles in 3 years I have to assume he/she was not a avid rider.

All it takes is one long high speed 80 mph brake to a dead stop can warp a rotor--especially if the rotor metal is low grade--maybe BRP ran out of normal rotors & filled their requirement with a Chinese knock off--we had a few arrive in the shop that anyone could spot the warping just by visual appearance..

[Bfromla]

Alignment sounds to be the culprit at this point, give Joe & Ann a call to get Squared Away. They can help show you more hands on too:firstplace: not sure if they were going to Spyders on the Bayou they may /may not have time in schedule :dontknow: 616-581-1304 & 616-340-9895
:thumbup: