Brake lever fading after some turns

[ROADTOAD1340]

I just made an appointment with a racing workshop to check the rim's and discs alignment, just in case. Fingers crossed

This is a good idea for elimination and peace of mind to clear those major pieces . All the lads recommended advice have been very good , I hope that you will now be well on the way to get a positive solution and outcome to your perplexing issue .
PS. I have made some peace with guitarrasa , I have admitted often being annoying and obnoxious .....and that I probably best leave it at that .... cos I'm off for a fun ride today !!

 

[guitarrasa]

I just put my Brembo rotors on and they are full floating. they move around pretty easy. the old rotors are also full floating, or used to be. they now appear to be seized. could that be your problem?

The seem to be OK, the move with their original play.
Has anybody ever had some tiny quantity of water inside the brake system?

 

[Bumblebee]

The seem to be OK, the move with their original play.
Has anybody ever had some tiny quantity of water inside the brake system?

It's been a few days, did you figure this out yet?

 

[guitarrasa]

It's been a few days, did you figure this out yet?

I'm taking the bike to a Racing workshop on Tuesday. I hope he can figure out what the problem is.
Of course I'll keep you posted in case we have to open some bottles of champaign

 

[Red05]

The seem to be OK, the move with their original play.
Has anybody ever had some tiny quantity of water inside the brake system?

Yes. After a big riding season and a cold winter, I had what I imagine to be moisture in the system, but a fluid change through regular bleeding took care of it. I hope the workshop finds the problem. To me it sounds like a rotor alignment problem since you've already eliminated a pad/rotor chemistry issue by trying different pads and rotors. You said the lever is solid and with the multiple bleeds I wouldn't think moisture is the issue.

 

[guitarrasa]

Yes. After a big riding season and a cold winter, I had what I imagine to be moisture in the system, but a fluid change through regular bleeding took care of it. I hope the workshop finds the problem. To me it sounds like a rotor alignment problem since you've already eliminated a pad/rotor chemistry issue by trying different pads and rotors. You said the lever is solid and with the multiple bleeds I wouldn't think moisture is the issue.

Thanks for telling us your experience.
I would also think it's something related to rotors alignment but to it doesn't make sense that the lever comes back to its initial feeling after some cooling time. Something is getting to hot and when it cools down it works again, but it's not the calipers cause their temperature is not high enough at all so.... Yeah, I hope the workshop can find it out.

 

[MLTMDNS]

I read this thread fast but have you put a dial indicator on your rotors?

 

[fallenarch]

Thanks for telling us your experience.
I would also think it's something related to rotors alignment but to it doesn't make sense that the lever comes back to its initial feeling after some cooling time. Something is getting to hot and when it cools down it works again, but it's not the calipers cause their temperature is not high enough at all so.... Yeah, I hope the workshop can find it out.

what about a seized piston on the caliper making the other overheat?

 

[Kiwi Rider]

what about a seized piston on the caliper making the other overheat?

To test your theory Arch, the wheel needs to be raised off the ground and spun, checking for drag caused by piston seized and applying pressure to the brake pad.
Has the OP checked the brakes for drag?

 

[guitarrasa]

I read this thread fast but have you put a dial indicator on your rotors?

Not sure what a dial indicator is

 

[guitarrasa]

what about a seized piston on the caliper making the other overheat?

Ruled out, happened with several calipers, these ones are 2 weeks old.

 

[guitarrasa]

To test your theory Arch, the wheel needs to be raised off the ground and spun, checking for drag caused by piston seized and applying pressure to the brake pad.
Has the OP checked the brakes for drag?

Calipers are brand new, rotors are fully floating so it's hard to tell if there's a light dragging

 

[MLTMDNS]

 

[guitarrasa]

Hi guys:
Workshop yesterday didn't quite work out. I left my bike there for 3 hours and they didnt even check it, said they were too busy, WTF?
So I'm over these twats.
Quick question for you guys, another long shot but it's worth to try. Do you think there could be some air trapped inside theses brake lines' tip? I just realised that they are originally made for the original MC which has an horizontal output instead of a vertical like Brembo/Accossato MC.
they make a 90 degree angle so....
See below