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Im running an R6 master cylinder, braided lines, race pads and zx6r calipers now but my brakes still feel rubbish after a few laps of hammering (levers nearly back at the bar) and having bled them more times than i care to remember im now on the look out for the best brake conversion for racing a zxr4. ideas welcome......ta

GSXR600/750 4 pots with brembo forged 19 x 18 radial master, SBS/Bendix carbon pads.
Lever solid as a rock with a ton of feel.
Regards,
MB

I agree with Mick, although the GSXR K6 radial master cylinder is nearly as good, and about £50 quid used on the bay. Levers are cheaper too..

The current R6/R1 MC is a radial also, I like vesrah pads but I don't know how popular how they are over there, I'm in the U.S. I've got ZX6r forks with radial calipers, never had a braking issue with them. How long since you have changed the fluid, bled the brakes. I bleed mine every race weekend.

Agreed Mark, really quite good with the standard marso, but the amount of feel of the brembo has to be tried to be believed.

Jim, I'd say your problem is more to do with fluid and pads. The R6 mc and ZX6 calipers plus braided lines should be up to the job. Try using a quality brake fluid like Rock Oil Racing (but then I would say that ) and some Performance Friction 95 compound pads.

As for how often to change fluid, I only do mine once a season.....couldn't be doing with every meeting

Alan P wrote:As for how often to change fluid, I only do mine once a season.....couldn't be doing with every meeting

I don't change the fluid every race weekend, but I do bleed the brakes every race weekend. When I used to race the old FZR400's with stock MC and calipers. my racing buddies always wondered how my brake lever felt so good. Never told them it was bleeding the brakes regularly, sometimes twice a day with those old brakes.

AFM327 wrote:........but I do bleed the brakes every race weekend

Crikey, sounds expensive and a lot of work, but whatever works for you I suppose

I took an 848 Evo out for a test ride on tuesday, gave it a hammering on the nearby a-roads. Yes it is fast, I saw 145 without even trying (I think I was in 4th...), but not very thrilling. Its 140bhp is spread over about 170-180mph of gearbox (if that makes sense = redline in top), so running through the gears from 30 on upwards doesn't feel much more thrilling than my er6 - which has 70bhp spread over about 120mph of gearbox; short and sweet. The difference is that it just keeps accelerating into seriously illegal speeds, and lots of jail time.

So in short the mad power wasn't that mad. Mildy irritated maybe, but not mad.

The brakes on the other hand... what we want are those monobloc brembos. I was warned about them, and even then I was surprised. This thing will stop from 140 down to 70 faster & harder than my er6 will do 50-0. Really, they were fantastic. Amazing. Wonderful. Scary...

Alan P wrote:

AFM327 wrote:........but I do bleed the brakes every race weekend

Crikey, sounds expensive and a lot of work, but whatever works for you I suppose

When your racing for first place an ounce or two of fluid and five minutes of your time isn't all that expensive when compared to other things like race fuel that is nearly $20.00 a gallon or tires, or is that tyres? Do you race?

Alan P is one of the fastest F400 riders in the contry and has plenty of wins

I dont race but do trackdays

My set up is gsxr600/750 4 pots, sbs dual compound pads and a zxr750 master cylinder, more than good enough for me

Rob

Surely the point here is why you would need to bleed brakes every meeting? Brake fluid doesn't 'go off' over a short period of time, it's an oil. The problem with it is that it's hygroscopic. So it's the absorbtion of moisture from atmospheric humidity whic degrades it, the water then turning to steam under braking and the resultant gas ruining the hydraulic power. There is no way you are going to get moisture absorbed into brake fluid in a sealed system over the course of a few weeks unless you are either leaving the system open to the atmosphere or some of the fittings are porous (dodgy old rubber hoses, poor reservoir seals etc). Or you introduced it in the first place by working in wet / humid conditions.

If you actually need to replace brake fluid each meeting (rather than doing it unnecessarily) I would suggest there is an underlying problem.

If hes using racing brake fluid (DOT5), then it absorbs moisture more efficiently and goes off quicker, so that could be one reason to change it so regularly?

I wrote a response the other day but I guess it didn't post.

No offense to Alan, I'm in the US and don't know who's a racer and who's not and you have to admit there is a difference between racers, track day riders and street riders.

That being said, I still contend it is a worthwhile practice. Anyone ever work with a BSB or WSBK team? I picked up this habit from some AMA mechanics and racers who mentored me when I started racing. How often do you clean your calipers? Mine get cleaned before every race weekend, soapy water and a toothbrush. Make sure the calipers and pistons are nice and clean. Walk around the BSB/WSBK pits and I'll bet you'll see the mechanics cleaning calipers in the afternoon/evening.

I use good fluid, Motul, only adding a small amount if needed each time. I generally don't need to add fluid each time. If you give it a try you will see that you'll get a small amount of air. If your doing it regularly it won't be much, but air is much more compressible than fluid. Every little bit helps, right?