Pulsing Front Brake.

A possible indicator of a warped disc is a brake lever that feels to have excessive range on the first pull, then feels normal on a second pull.

A warped disc, esp a badly warped one, will gently nudge the pads back into the calipers, hence the first pull on the lever feeling less effective as it's partially just pushing the pads out to where they should be.

Dont know if this can help but I had a « pulsing front brake » - thought it was a warped disc

However a few weeks ago I cleaned up my front callipers (removed, washed etc), reinstalled them with the same brake pads and the pulsing was gone

Must have been a build up of crud or something ……

I had the same issue, the discs were slightly warped but within spec. Same for the thickness variation (most likely cause of the pulsing).

Still the dealer received an approval from BMW to replace the discs. Bike has about 2K miles on it.

digby said:

Dont know if this can help but I had a « pulsing front brake » - thought it was a warped disc

However a few weeks ago I cleaned up my front callipers (removed, washed etc), reinstalled them with the same brake pads and the pulsing was gone

Must have been a build up of crud or something ……

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If you hold the bike on the brakes when the disk and pads are already very hot from riding eg waiting at a junction or on a slight hill, a small amount of pad compound/brake dust can bond onto the disk surface, causing a drag spot on the disk that you can feel through the lever. Cleaning the disks with brake cleaner and a scotchbrite pad can restore smooth braking feel.
I try to avoid the habit of sitting on my bike in traffic with the brakes applied (obviously if you are on a hill you have no option.)