600RR: Anyone else with brake issues??

Hello All,

I have a 2008 600RR which has been a trackday bike for a number of years, now. I've never had any technical issues with the bike before. However, toward the end of last season I started having brake system issues. Some very serious fade at Barber which ended the day early (luckily no crash) started the brake problem saga.

After that, I flushed the system, replaced pads with new Vesrah race pads, rebuilt the master cylinder and both front calipers, replaced both front rotors, and put in some Motul RB660. I don't suspect any of the work done or components replaced to currently be at fault. My last few trackdays were at Tally. At the beginning of every session the brake feel was solid, but things got squishy at the end of every session; no fade, but a definite drop in feedback. I would bleed fluid between sessions to ensure a nice solid feel, but couldn't ever actually find air entering the system, nor could I ever find a leak anywhere.

By process of elimination, the only other components left to be a fault would be the brake lines (which are still original parts). So the question is this: are there any 600RR owners out there who have had similar experiences in feel with stock lines, replaced them with new lines (OEM or stainless), and resolved the problem in that way? Similar experiences with other makes are also welcome input.

Thanks

 

I've never purchased braided lines for a bike before. Any recommendations on a good brand? Any brands to stay away from?

 

Thanks for all the input, folks. I have some Spiegler lines, front and rear, on the way. Went with the 950 (3 line) front kit because I like how tidy they are compared to other options. I'm also going to go ahead and rebuild the rear caliper and master because the seals there are old as well.... even though I never touch the rear brake.

 

UPDATE

This is to benefit anyone in a similar situation with troublesome brake problems, here's a roadmap of my experience:

Problem statement:

-Under trackday use, very serious brake fade ended my day early

Steps/results:

-Flushed brake fluid from old RBF600 to new RBF600 --> serious fade eliminated, mild fade remained
-Rebuilt caliper and master cylinder with new seals everywhere, new master cylinder piston, checked all bore measurements, thoroughly cleaned everything prior to reassembly, swapped in new race pads and rotors, swapped in speed bleeders for convenience --> fade decreased but still present, no improvement in brake feel, unacceptable amount of air entering system, bled brakes between each session
-Replaced factory lines with braided stainless kit --> fade eliminated, feel improved, very small amount of air entering system over the course of 10+ hard sessions, slightly diminished stopping power over course of a race (route cause of this was small amount of air entering system somewhere)
-Swapped back to factory bleeders, factory banjo bolts (spiegler banjo bolts are aluminum and have lower preload capability), and Goodridge banjo sealing washers --> all problems resolved

Critical learnings:

1. Use quality pads and rotors selected appropriately for intended end use
2. Flush brake fluid atleast once per season, maybe more, use a high-quality fluid appropriately selected for components in use and intended end use. Know how to flush brakes properly
3. Factory seals in calipers and master cylinders have a life of less than 10 years for a track bike
4. Factory lines have a life of less than 10 years for a track bike
5. Stainless lines help improve feel but they don't eliminate fade issues. I don't recommend using aluminum banjo bolts or Aluminum sealing washers because they have lower preload limits and, therefore, less sealing capability than steel bolts and copper sealing washers.
6. Unless a vendor comes up with something new, I don't recommend speed bleeders for motorcycles. The goodridge speed bleeders were the most likely culprit for the air entering the system problem I chased for so long. Based on the wear marks, the sealing face on speed bleeders looks to be either undersized OR at the wrong angle to work as well as the factory bleeders for sealing.
7. It is impossible for a system to feel EXACTLY the same in the pits vs. after a hard session. Even if there is nothing wrong with braking performance, to the extremely discerning rider, a hot system feels slightly different than a cold system.

I hope someone gets something out of this and is able to avoid all the troubleshooting I had to do in order to finally get my system working right again.