[missusfinz]

Hi
When I brake my bike shudders. I feel like the rotors are warped.
Is there any other reason for this or is time to replace my front rotors?
I've ridden 68,000 kms (40,000 miles)
Thanks,
Ellie

 

[AntRT]

How old/miles are your pads?

 

[four12]

Two years ago, my F800ST developed a really bad front brake shudder.

I took it to the shop and they said that there was a service bulletin issued for the K and R bikes dealing with the issue, but that it hadn't been noted for the F series.

Being the excellent service shop that they are (Ride West BMW), they replaced my front rotors and pads under the service bulletin.

So... not sure how old your bike is, but you might want to query your dealer and see if the bulletin applies.

 

[hopz]

It seems likely that you have warped rotors.

With 40,000 miles I wonder if there has been a situation where they got really hot, or even sustained a blow/trauma of some sort.

Not that hard to diagnose but a PITA. If you have a dial indicator you might be able to set it up to measure the run-out of the discs.

But, if at 40K mile you are developing some circumferential ridging in the rotors it might be time to think about changing them anyway.

 

[beech]

Had this issue on my k bike. Figured big dollars for rotors coming up! This was at 40K miles also. I needed new pads and installed them figuring that I'll need new pads no matter what. I'll put new pads in and just see what is happening then buy rotors right away if needed. Well now no shuddering. So, not always rotor failure.

 

[missusfinz]

Had this issue on my k bike. Figured big dollars for rotors coming up! This was at 40K miles also. I needed new pads and installed them figuring that I'll need new pads no matter what. I'll put new pads in and just see what is happening then buy rotors right away if needed. Well now no shuddering. So, not always rotor failure.

Hi
Thanks for the input.
I was curious if it could be something other than rotors.
Ellie

 

[Firenailer]

You might want to give them a check to be sure no oil or grease has gotten on them. That will cause a similar symptom.

 

[missusfinz]

You might want to give them a check to be sure no oil or grease has gotten on them. That will cause a similar symptom.

That's a good idea.
I do clean the bike with Turtle ice. I wonder if overspray is getting on the rotors. I clean my bike after every ride.
I'll leave her dirty for a few rides.
Thanks,
Ellie

 

[AntRT]

Easy way to check rotors is with a ruler. Put the bike on the center stand and spin the rear wheel while holding a ruler as close as possible to the rotor with out touching. If it's warped you'll see it wobble between the distance from the rotor and the ruler. For the front same thing but you'll need someone to help you raise the front wheel.

 

[JPSpen]

Actually, If you'll look inside the caliper while spinning the tire.. You might be able to see the disk moving between the brake shoes if there's any runout....

John