I get the same problem, when the brakes get hot the lever comes back almost to the bar. Still stops but does make me feel too confident.

Problem is that the OEM master cyclinder is not radial like the brakes and has to travel further to create the same level of piston movement in the caliper.

Brembo Radial master cyclinder fixes this and I'm told works really well. Planning to do this myself.

Someone on this site has already done the mod so hopefully they will tell all.

 

Damn $250 freaking overpriced shit... Oh well. I need those better brakes. When your at the 5 marker running 145 it's time to brake and I need to know she's gonna stop before we see straw!

 

well said [smilie=b:

In the UK that same piece of shit cost $400........ :shock:

 

Stock pads on this bike suck, IMO. I've changed to Galfer lines and Galfer HH pads. Much better initial bite and feel, and not nearly as spongy with less fade.

Also went with the CRG levers. It's very nice to be able to get more lever when the brakes get hot at the track, just by thumbing the click adjustment out a bit while still riding.

I'm still not thrilled with the brakes, but they are much better after making these 3 changes. I may end up going for the new master cylinder anyway, tho. Coming from a 954, the 10R excels in just about every respect, except for the brakes. The 954 spoiled me with the best brakes I've ever ridden on a stock bike and I've been trying hard to get the 10R to come close.

 

I'm with CC on this one, toss the stock pads. They're hideous compared to the Galfer hh. I changed the pads a week before the lines, the pads are 100% better. Didn't see that much of a difference after I changed the lines.

 

I installed the Galfer brake lines and Galfer HH pads. After careful bleeding of the brakes, I had NO sponginess at the lever. I have seen very few people bleed brakes correctly. After a track day at TWS which features some pretty heavy braking, I had no fade, no soft lever. Just great brakes. And I would bet that the other riders in the advanced group will tell you that I do use my brakes. LOL The reason the lever gets more spongy (assuming you have steel braded brake hoses) is air in the brake fluid. As the fluid heats, the air bubbles expand, which increases the spongy feeling and requires more lever travel to move enough fluid to stop the bike.

As far as a radial pump moving more fluid, it is simple mechanics. A piston of a certain size will always displace the same amount of fluid for a given stroke. In other words a 17mm piston traveling 1/4 of an inch will always pump the same amount of brake fluid. Radial master cyl, std master cyl, it don't make no difference. A larger piston will move more fluid for the same stroke, but requires more effort to achieve the same braking effort. And if you have air in your lines, you will still have spongy brakes.

 

The reason the lever gets more spongy (assuming you have steel braded brake hoses) is air in the brake fluid. As the fluid heats, the air bubbles expand, which increases the spongy feeling and requires more lever travel to move enough fluid to stop the bike.

In addition, brake fluid absorbs water like a bastard. As it absorbs water, its boiling point goes down; then, when your brake system heats up, the fluid boils and you now have bubbles in your line.

Besides making sure that your brake fluid is dry and fresh, another important thing is to use better brake fluid. I've replaced all the hydraulic fluid in my bikes with ATE Super Blue racing brake fluid, whose boiling point is much higher (both wet and dry) than DOT 4. In the long run it makes a big difference.

 

Already using syn dot 4 stuff... The fluid has never been hot enough to reach those breakdown temps until this past weekend.... The fluid is new as well... Like 2 months of street riding. Maybe 800 miles.

I am totally stumped.

 

I used synthetic brake fluid in my road race car and it sucked. BIGTIME. When I continued to have problems I got this elaborate technical explanation that every junction, every fitting, any surface irregularity would "shear" the synthtic brake fluid and create air in the brake system. That sounded like BS to me but for whatever reason, I never got decent brakes with synthetic brake fluid. I had much better luck with Castrol LMA than I did with the super exotic synthetic brake fluid. I also noticed in the instructions that came with my Galfer hoses and pads that they mentioned something about not using synthetic brake fluid.

 

Already using syn dot 4 stuff... The fluid has never been hot enough to reach those breakdown temps until this past weekend.... The fluid is new as well... Like 2 months of street riding. Maybe 800 miles.

I am totally stumped.

Motul has a brake fluid which is better than dot 4 check out our sponsors I think they both carry the stuff

 

When you changed the pads, did you put the little stainless inserts back on the new pads? If so, remove them and you'll remove some of the spongy feeling from the lever. Also, For track days you may want to remove the anti-rattle springs from the pins holding the pads in the caliper. This will allow for more airflow through the rotor/caliper and cool the brakes more effectively. These changes made a big difference in the feel of my 7R's brakes and my 10R's as well.