Noisy, inconsistent and stuttery front brake (Magura MT7)

[Rip]

Difficult one to explain but I'll do my best. My front brake when pulled on anywhere from about 20% - 70% while the bike is moving (like when doing a rolling stoppie or similar) makes a weird noise from the pads and rotor and the actual braking isn't smooth and consistent, it feels lumpy and stuttery. My rear brake is absolutely fine and I can feather it perfectly to save or slow down a manual. I've had this issue with the front brake pretty consistenly throughout 2 sets of rotors (both Magura Storm HC's) and 3 sets of brake pads (Magura Blue, Green and Grey) so I'm 100% sure it's not a hardware issue. Is it simply because the front hasn't had a chance to bed in properly because I use the rear so much more? I'm pretty sure after fitting my current set of pads (Grey) and bedding them in I swapped the fronts and rears over to try to stop this from happening but it's obviously happening again, maybe I need to swap them back again, or even swap the rotors over front to back?

Just to add a mate of mine's front brake is exactly the same, same MT7, same noise, same lumpy stutter so obviously we're both doing something wrong.

[AdamR28]

Perfectly normal, means the brake is working well.

[Rip]

58 minutes ago, AdamR28 said:

Perfectly normal, means the brake is working well.

Haha maybe I didn't explain it very well, the way it is I couldn't feather it enough for fakie nose manuals or nice smooth rolling stoppies leading into a g-turn. I'm not disputing what you are saying at all, just wondering why the rear is nice and smooth and controllable but the front isn't?

[AdamR28]

Sounds like the rear is a little contaminated / not working 100%.

The rotor design gives a sort of 'ABS' from the solid-holes-solid-holes pattern. Can't feel it on MTB much but very apparent at slower speeds. A rotor with 'consistent' braking surface should do the trick.

[Rip]

47 minutes ago, AdamR28 said:

Sounds like the rear is a little contaminated / not working 100%.

The rotor design gives a sort of 'ABS' from the solid-holes-solid-holes pattern. Can't feel it on MTB much but very apparent at slower speeds. A rotor with 'consistent' braking surface should do the trick.

Rear is definitely working fine, tons of holding power under load but I know what you're saying. Exactly the same on my mates bike, rear is smooth, front feels horrible. Interesting about rotor surface, maybe I'll try a different rotor for science, I'll see if Magura do one without holes. 

[MaderaMark]

pad rocks, loose rotor bolts, caliper bolts or maybe air/contamination in brake system?

[Rip]

3 hours ago, MaderaMark said:

pad rocks, loose rotor bolts, caliper bolts or maybe air/contamination in brake system?

Definitely none of the above, I'll see if I can capture it on video to better explain it. Also the fact that my mates bike is exactly the same (rear fine, front weird) points away from something actually wrong with mine. To rule it out though I will swap my front and rear rotors and pads around front to back. 

[MaderaMark]

try swapping caliper / rotor. headset not loose as well?

 

[La Bourde]

The root cause could be a lack of rigidity of your fork, hub or brake adapter. This can lead to some sort of resonance. One friend, who is on the heavy side had this on a steel frame(rear brake)

In your case I doubt it.

Another root cause could be a bad facing of the fork mounts, leading here also to a resonance issue. The pistons of the caliper have then a slight angle, that will damage the seals. I had a similar issue with an old marzocchi fork (2001) and had to replace the seals of the Hope brake.