Warped rotor?

[View from behind]

We have an ongoing issue with our 2015 RT limited. What seems like a warped rotor on the front left wheel. What happens when applying the brakes is a pulsing in the brake pedal and hand brake (after market) and an obvious vibration in the left front fender. One thing that seems odd is that the condition is not bad when first starting out but after some time the pulsing and fender vibration become almost violent. The rotor was replaced a couple of years ago without any significant change. Our Best warranty is coming to an end and we want to have it looked at again. It seems unlikely that the rotor would warp and then return to a neutral state after sitting for a while. Because of the pulsing, it seems unlikely that anything other than a brake component would be causing this. Any suggestions?
Thanks in advance.

 

[Peter Aawen]

Are you still running ANY OE Spec Kenda tires? You wouldn't be the first to discover a vibration like that came down to a dodgy Kenda tire &/or the rim being either out-of-round or just so poorly constructed it caused those issues!! :gaah:


If you can, try swapping your (front) tires & rims with another set - preferably from another Spyder, & preferably from one that doesn't have this pulsating/vibrating fender problem; but if you can't do that readily, even just swapping your existing wheels from one side to the other might help with the diagnosis, especially if the fender vibration changes to the other side along with the wheel. :lecturef_smilie:

Only please do tell us what you do along those lines & if it makes any difference at all..... :dontknow:

Good Luck! :thumbup:

 

[View from behind]

Thank you for taking the time to respond. We are not running Kenda tires however not sure why there would be a vibration only when the brakes are applied? If the wheel was out of round I would think it would vibrate all the time.

 

[JayBros]

You can check rotor warpage with a large piece of glass and feeler gauges. As the rotor heats up the warpage could increase thereby increasing the pulsations and fender vibration. No, having warpage completely disappear and then reappear is extremely unlikely to virtually impossible. Although I've not heard of it with Spyders, some automobiles in the past, particularly Ford Explorers to my knowledge have incurred warped rotors as a result of improperly torqued lug nuts.

 

[View from behind]

JayBros,

Thanks for taking the time to respond. Had the Spyder serviced recently where brake pads were replaced and the dealer said try that and see if it solves the problem. The first thing I did when I got it home was to remove then torque the lug nuts. How much warpage would it take to make this happen and when I remove the wheel will I have access to make the measurement or do other components need to be removed?

 

[splake0]

JayBros,

Thanks for taking the time to respond. Had the Spyder serviced recently where brake pads were replaced and the dealer said try that and see if it solves the problem. The first thing I did when I got it home was to remove then torque the lug nuts. How much warpage would it take to make this happen and when I remove the wheel will I have access to make the measurement or do other components need to be removed?

I think you’re going to have to replace the brake caliper. With my experience with similar issue. That’s what I had to do.

 

[View from behind]

splake0,

Thanks for taking the time to reply. Were you experiencing the same symptoms and how was it determined the caliper was the issue?

 

[splake0]

splake0,

Thanks for taking the time to reply. Were you experiencing the same symptoms and how was it determined the caliper was the issue?

Did not happen on a Spyder but happened twice over the years on my pickup. First Replaced pads. Didn’t work. Second replaced rotors. Did work for long. Thirdly repacked brake caliper. Solved the problem.

 

[BajaRon]

Sometimes, correctly diagnosing the problem and finding the offending part(s) is 95% of the cure. Rather than throw parts and money at the problem. There are some things that you can do to, at least, eliminate some possibilities.

It could be a tire problem, as mentioned above. Not likely with the symptom's your having. But still possible.
It could be a warped rotor issue. Very possible. I've had a number of customers replace rotors several times, only to have the problem re-occur.
It could be a caliper problem causing a rotor problem. This is easily checked. Wear on the front pads should be fairly even. If one pad or both pads on one side are wearing faster than the other side. This is an obvious clue. You can also ride for a distance without using your brakes at all, pull over, coasting to a stop without using your brakes except at the very end to come to a complete stop. (Finding an uphill run-out area helps) Then check the front calpers/rotor temps. They should both be at least cool, if not cold. If one side is significantly hotter than the other. Then you have found your culprit.
It could also be worn A-Arm bushings. These will give you a definite shudder when braking. Simulating a warped rotor. You can check this by elevating the front wheels. Taking a firm grip on the wheel and forcefully moving it forward and back. Feel/listen for any movement or slight clunking sounds.

I hope this helps. It will be interesting to find out what cures your problem.

One suggestion. You can get 2 EBC rotors for about the price of 1 OEM rotor. EBC rotors are of a much higher quality. I've had customers who have warped as many as 3 sets of front rotors. They installed a set of EBC rotors and never looked back. I've never had a customer warp an EBC rotor yet. If you find a warped rotor is your problem. This is definitely the way to go.

You have to purchase 2 rotors for the front as a set. Because the EBC rotors stop better than the OEM rotors. You can't replace just one side. This would give you uneven braking at the front. Which would create a very bad situation.

 

[JayBros]

JayBros,

Thanks for taking the time to respond. Had the Spyder serviced recently where brake pads were replaced and the dealer said try that and see if it solves the problem. The first thing I did when I got it home was to remove then torque the lug nuts. How much warpage would it take to make this happen and when I remove the wheel will I have access to make the measurement or do other components need to be removed?

If you remove the left wheel you get the best view of the brake pads and how close they are sitting to the rotor. The first thing I would do is,with the ignition turned off, press and release the brake pedal and see if both pads retract when you release the pressure. One or both of the pads may be lightly kissing the rotor but there is nothing wrong with that. I recommend if you are going to handle the rotor use nitrile gloves so you don't contaminate the it with any grease and be prepared to clean the rotor with brake cleaner or alcohol before reassembling everything. You could use the eyeball method and turn the rotor to see if there is visible warpage. It you cannot detect visible waprage, switch to feeler gauges and see if the rotor binds up as you increase the thickness of the feeler gauges. If you want to try the plate glass method you will have to remove the caliper but that is only two bolts. There should be thread locker on the bolts and it may take some muscle work to break them loose. Clean and apply Blue Loctite when reinstalling the bolts and torque them to 50 lbft. If you remove the caliper, DO NOT let it hang by the brake fluid line. Also, if you remove the caliper press both of the pads outward to fully retract the pistons and it will make it much easier to slip the caliper over the rotor. When you have reinstalled and torqued the caliper depress the brake pedal several times to reseat the pads close to the rotor. I think it would be quite unusual if there is a problem with a Brembo caliper but Murphy was an optimist.

 

[View from behind]

BajaRon,

Thanks for taking the time to reply. I don't think it's a tire problem as this has continued beyond a tire change. I will look at the pad thicknesses and have done a similar temperature check when stopping at the end of the day and have not felt a significant difference in temperature with being able to touch and hold both the front rotors. Would the A-Arm issue cause a pulsing in the brake line?
By the way, I have your sway bar and love it.

 

[View from behind]

JayBros,

Thanks for your help.

 

[Mikey]

When you put your hand brake on, is that when your problem started? You sure you bled all the air out of the system when you did it? Just putting it out there!

 

[View from behind]

Mikey,
Thank you for taking the time to reply. No, it has been a problem right along.

 

[Mikey]

You jack it up and spin the tire a little at a time do feel a slight drag on that side, like a pad rubbing?

 

[BajaRon]

BajaRon,

Thanks for taking the time to reply. I don't think it's a tire problem as this has continued beyond a tire change. I will look at the pad thicknesses and have done a similar temperature check when stopping at the end of the day and have not felt a significant difference in temperature with being able to touch and hold both the front rotors. Would the A-Arm issue cause a pulsing in the brake line?
By the way, I have your sway bar and love it.

Yes, worn A-Arm bushings can give you some pulsating at the brake peddle. I think it is the shaking action that causes this. But I am still leaning towards a warped rotor. But don't rule out anything. Fixated or Tunnel vision is bad in just about every situation. I'm not there. I'm just guessing.

 

[View from behind]

BajaRon,

Thanks again, I will jack it up tomorrow and do the A-arm test and look at how even the pad wear is and if I don't see anything there I will order the new rotors that you suggest. I'm assuming a pretty simple install?

 

[BajaRon]

BajaRon,

Thanks again, I will jack it up tomorrow and do the A-arm test and look at how even the pad wear is and if I don't see anything there I will order the new rotors that you suggest. I'm assuming a pretty simple install?

Yes, the good news is the rotors are quite easy to install. You have to remove the calipers. But you may have to do this anyway to really get a good read on the pad wear. However, since you have already done the rotor/caliper temperature test with no significant difference. It would be unlikely to have a caliper or pad wear issue. If you can't get any movement out of the A-Arms or Tie Rod Links. I'd say you've narrowed it down to a warped rotor. I wish I could guarantee this for you. But I feel pretty confident that a set of rotors will cure your problem baring loose suspension components.

 

[JayBros]

...But I feel pretty confident that a set of rotors will cure your problem baring loose suspension components.

If there are no suspension components involved and you switch to EBC fully sintered pads and rotors (you needn't do all three wheels at once but when you have all three done) and follow Ron's instructions for pad installation and bedding in, the brakes will stop you like the hand of God.

 

[View from behind]

JayBros,

Thank you