What could this weird fender vibration when braking be?

[Two2Three]

I recently had new tires put on my 2022 RT Ltd, Vredestein Quatrack 165/60R-15 on the front, 215/60R15 rear.

I've ridden it for a couple hundred miles with no issues, but today was a very quiet day, (no wind noise to speak of, and I had the radio off) and when I brake, I noticed I can hear a dull vibration sound. It sounds like a kid making a motorboat sound by purring their tongue or something (yeah, hard to describe), and I can see the left fender vibrates forward and back slightly. I can feel the vibration when I put my left boot against the fender while braking.

I can't feel anything actually loose by just pushing/pulling on the fender when stopped. It feels just as solid as the right fender.

Any ideas what it could be? I've never taken the tires off myself... it was done at a powersports shop that is familiar with Spyders. Just not an actual Can-AM dealer. Maybe it's normal and I just never noticed it, but I'd think I'd have heard it sometime if that was the case.

 

[fatboy]

check the light possible loose or the front two bolts that hold fender strut broke

 

[Two2Three]

The light definitely wiggles back and forth, and I can maybe convince myself that is the cause. Though the light on the other fender wiggles the same way and there's no noise there.

The fender itself seems solid. I can't move it at all by hand.

 

[Snowbelt Spyder]

Check your lug nuts torqued. Plus, you might even simply have a bit of brake pad deposit on that rotor.

 

[Two2Three]

Check your lug nuts torqued. You might even simply have a bit of brake pad deposit on that rotor.

Interesting. I didn't consider the torque, but I set my wrench to 80 ft lbs (manual says 77-83) and got about 3/8" turn out of one nut on each wheel. The other two were already at or above that. We'll see if anything changes when I take it out tonight.

 

[BajaRon]

Interesting. I didn't consider the torque, but I set my wrench to 80 ft lbs (manual says 77-83) and got about 3/8" turn out of one nut on each wheel. The other two were already at or above that. We'll see if anything changes when I take it out tonight.

I would start over on the wheel torque. Back all 3 off to below torque spec and retighten. That's the only way to be sure it's correct.

 

[Two2Three]

I would start over on the wheel torque. Back all 3 off to below torque spec and retighten. That's the only way to be sure it's correct.

I'll do that before I take it out. Good idea.

 

[spyderdave]

If backing off on wheeel torque doesn't solve your problem, consider putting a dial indicator on your rotors; they might be starting to warp. Ya, kind'a outside the box, but my 2020 RTL was doing something similar after about 5K. If you don't have access to a dial indicator, make one out of a "Sharpie" and a zip tie.

 

[BertRemington]

Concur with BR. Ya gotta start over. Best to lift each wheel off the ground, completely release the lug nuts, snugly tighten until the wheel starts rotating, then return to ground lightly for final torque. I like to sneak up on my lug nuts: first 50 ft-lb then 80 ft-lb.

 

[Mikey]

If the retorque don't work maybe you have a little pad glazing going on, or hard spots on that rotor. This is one of those things that would be easier to see in real life. I would maybe take that whole brake assembly apart and give it a good cleaning, give the pads a LIGHT scuff with some light sandpaper, and look the rotor over well for warps or blemishes. Check the wheel bearings for play.

 

[SpyderJerry]

I just went through that on a 2014 RT SE6. I bought it with issues and the front right shaking when applying the brakes was one of them. Replace rotors and pads, had same problem, same wheel. Replaced A arm bushings, same problem. Long story short, I dial indicated the rotor and found .0012" run out and .0004" parallel. Installed the good rotor from left side and all is smooth. The luck of getting a new bad rotor and installing it on the same side with the problem.

 

[BajaRon]

If you find that it is your rotor(s). I highly recommend replacing them with EBC rotors. Much higher quality, better stopping power, and 2 EBC rotors will cost you about the same as 1 OEM rotor. I've had customers who warped as many as 3 OEM rotors before they upgraded to EBC. Never had a problem after that.

Do not mix rotors on the front wheels. If you go to a different rotor, replace both. Otherwise, you will get uneven braking and this is not good.

 

[Two2Three]

Thanks everyone for the replies. So I think it's all sorted now.

As I mentioned, there was one nut loose on both front wheels. It seemed like after tightening them, when I rode it last night that the sound was way less. So this morning I jacked it up, loosened all lug nuts, made sure the wheels were pushed in fully seated, and snugged them up. Then lowered the bike down and torqued them all to 80 ft lbs. Rode about 50 miles at lunch and didn't hear anything. Then just checked one more time around the neighborhood with my helmet off testing the brakes several times and didn't hear anything.

So apparently it was all caused by the lug nut not being fully tightened.

I do think I may have a slight warp in at least the left side rotor, because when I turn the wheel I can hear it rub at one point per rotation slightly. Can't hear that when riding though.

Maybe after a lot of riding and braking when the pads are hot, that could make a more pronounced sound? I don't know. But I know the pads are only about 50% gone.

I'll make a note to check out EBC rotors if they do warp. I've used EBC red ceramic pads in a car several years ago, so I'm somewhat familiar with the brand.

 

[Deanna777]

I am just putting this out there, did you have an alignment done?

Deanna

 

[Two2Three]

I am just putting this out there, did you have an alignment done?

Not unless they did it as part of the tire swap. I didn't request it specifically.

 

[Deanna777]

Not unless they did it as part of the tire swap. I didn't request it specifically.

Were the tires balanced?

Deanna

 

[Woodaddict]

So apparently it was all caused by the lug nut not being fully tightened..

Did you inspect the rim any wallow in the nut areas? That is just sloppy tightening on nuts. I would NOT use them again!!! With those air wrenchs, they could have overtightened 1 of them, even stretched the thread studs a little, even warped the hub!! Which also holds the rotor, which could cause the brake surging. These rims are ALUMINUM, doesn't take much movement to alter a FLAT backing to hub to be out of wack!!

 

[Mikey]

Thanks everyone for the replies. So I think it's all sorted now.

As I mentioned, there was one nut loose on both front wheels. It seemed like after tightening them, when I rode it last night that the sound was way less. So this morning I jacked it up, loosened all lug nuts, made sure the wheels were pushed in fully seated, and snugged them up. Then lowered the bike down and torqued them all to 80 ft lbs. Rode about 50 miles at lunch and didn't hear anything. Then just checked one more time around the neighborhood with my helmet off testing the brakes several times and didn't hear anything.

So apparently it was all caused by the lug nut not being fully tightened.

I do think I may have a slight warp in at least the left side rotor, because when I turn the wheel I can hear it rub at one point per rotation slightly. Can't hear that when riding though.

Maybe after a lot of riding and braking when the pads are hot, that could make a more pronounced sound? I don't know. But I know the pads are only about 50% gone.

I'll make a note to check out EBC rotors if they do warp. I've used EBC red ceramic pads in a car several years ago, so I'm somewhat familiar with the brand.

You may have to tighten that wheel bearing just a touch, check the free play on that side!

 

[BajaRon]

Not unless they did it as part of the tire swap. I didn't request it specifically.

Then you can be sure that you didn't get an alignment. But it doesn't sound like an alignment issue anyway. If you were out-of-balance, you'd get the problem all the time, not just when braking. It's most likely something loose, rotor issues, or A-Arm bushings.

 

[SpyderJerry]

I just went through that on a 2014 RT SE6. I bought it with issues and the front right shaking when applying the brakes was one of them. Replace rotors and pads, had same problem, same wheel. Replaced A arm bushings, same problem. Long story short, I dial indicated the rotor and found .0012" run out and .0004" parallel. Installed the good rotor from left side and all is smooth. The luck of getting a new bad rotor and installing it on the same side with the problem.

Ron, those were EBC MD853 rotors