? - Effects of brake line configuration.

Piston travel will be the same, since you still need to move the same amount of fluid with the same piston. You actually move very little fluid, by the way, what is mainly happening when you apply the brakes is a transfer of pressure. The next time you are bleeding your brakes, pull the lever in the same distance as you do when applying the brakes and see how little fluid comes out.

 

what matters is the ratio between the piston driven by the lever and the pistons in the calipers that it drives. If you dont change either of those you wont change the feel, except that lines and fluid are not perfect. more line equals more flex and more fluid equals more compression of the fluid, both detract from performance, so you want the least amout of brake line that does the job.

 

To affect the pull, the line would need to be the size of a pilot jet. In the size range of real brake lines the won't be any difference.

How mch resistance is there with the bleeder open?

 

I have run both line setups on my 998R and my 999R and I had the same master/calipers you do and I couldn't tell the difference between either.

 

I went to the dual lines on my 749, and I really can't tell a difference. I think the better move would be to upgrade the master cylinder.

 

Vesrah Super RJL's

The billet radial is just a way to spend more money.

 

Sorry Jesse, didn't see you already had the brembo master...

 

So you like the Vesrah pads better then the Carbone Lorraine C44's?

 

Yeah, but brake pad performance is a lot like women. I’m sure we can all agree on the ones that are hot. But out of the ones that are hot some of us will like this kind and others will like that kind, etc.

I like the Vesrah pads because of how they work. They have a pretty aggressive initial bite but not so much so that it wants to unsettle the chassis or makes you want to add compression to the forks to deal with it. Don’t get me wrong, they bite. But if you roll into the lever it’s seamless. Then I like a pad that works like a rheostat. I pull A it slows A, I pull B it slows B, etc. I like a linear power increase that matches my lever pressure. In my opinion that is the ultimate in brake control if you can get them to do that. A good example is braking for turn 1 at Grattan. If you look at the brake zone from the pits you can see that there is a long “lump†in the track that runs from about of a quarter of the way into your braking zone till about a quarter from when you tip it in. The end of the lump acts like a bit of a “jump†and if you are 10/10th braking you can go over the top of it and it will try and lift the back wheel on you pretty good and at the least put just enough of an input into the chassis to delay your ability to turn the bike in. If the end of the lump does chuck the rear end up in the air a bit chances are you will be trying to tip in with it still off the ground. It can be done without killing yourself but it does make for a bit of fun mid corner.

The Vesrah’s have so much linear feel to them that I can lighten my brake load right when I get to the end of the lump and then load them right up after I have gone over it and keep the chassis as steady as a rock through the whole process. In reality they are allowing me to roll off the brakes just enough to get the fork travel I need to cope with that lump/bump/jump and then get right back on them and have the fork travel set back where I want it (just about bottomed) to get the bike turned in.

They are also real nice because you don’t have to bed them in. I have started races with new pads and the warm up lap was the only bedding they got before the flag flew. I have never come across another pad you can do that with and I have turned a few sets of EBC HH and HHH’s into “wood†because I didn’t bed them in enough before using them.

I have never ridden with a set of Carbon Lorain’s so I can’t offer a back to back comparison.

Brake pads are just one of those things that you need to test and see what you like. It’s the same with where you set your clip ons and rearsets. I have had people jump on my bike that are almost exactly the same size as me and say “How do you ride this thing?†There are a ton of little tiny things that add up to a “good bike†for you as a rider. You have to play with them sometimes to see what you like. You want to tailor the bike to you, not tailor your riding to the bike when it comes to things like brake pad feel, lever position, rearset height, handlebar width and angle, etc. Then you can get into the real nit picky stuff like how thick your seat foam is, etc. Take a look at the Yosh pit for example. There will be three Superbikes sitting there and they will have three completely different riding positions, etc. I would be amazed if all three riders used the same brake pads. They probably all don’t even use the same master cylinder dimensions.
So what is the best set of brake pads? The ones that work with the way you want to ride the bike.

 

I agree with Mike, (Desmo46), it doesn't matter as long as the system is bled of all air.

Per the original brake line routing question. In my opinion its easier and quicker to bleed the two separate lines from the master cylinder to the calipers (Y - routing) than it is when one line goes from the master cylinder to one caliper and then over the fender to the next caliper (h - routing). Because so little fluid moves with the application of the master cylinder I feel air bubbles get trapped in the top portion of the line going over the fender and only with great difficulty does one get it out.

I had great difficulty bleeding an h-routed brand new 2008 Kawasaki last year and what I eventually did to get all the air out of this system is this:

1 - apply the master cylinder to push the pistons out as if the brake pads were almost worn out (I used a thin block of wood for the pistons to work against so they wouldn't fall out),

2 - then I emptied the reservoir with a syringe and finally pushed all the pistons in until they bottomed out in the caliper.

On the Kawasaki it was on the left side caliper first and then on the right, working from the piston most distant from the hose to the one closest. All of this is to encourage the fluid and hopefully air too to flow back up to the master cylinder (After pushing the left side pistons in I used small Quick Grip clamps to hold the pistons fully depressed).

Only after all this could I get a firm and consistent brake application. Prior to this the brakes worked but were amazingly spongy (and lacking in feel, needless to say non-confidence-inspiring). AND all of this was regardless of stock lines or with aftermarket braided steel lines. I tried bleeding this motorcycle with a vacuum bleeder (power bleeder) with the aid of an assistant to apply the brake and some other "tricks" that have worked throught out the past. What this finally led to was the conclusion that air was trapped in the line going over the fender, not at the master cylinder or banjo bolt area. I needed a large volume of fluid to pass through the hose, not a small dribble.

BTW I've been doing this kind of work for nearly 30 years as a hobby and I've never had this much trouble before. I notice that the Suzuki sport bikes are like this and I wonder if the brake fade they were experiencing a few years back in super sport club racing was because of this.

 

P.S. I've noticed that many(most if not all) aftermarket steel lines are configured with two lines from the master cylinder (one to each caliper). With the 2008 Kawi I mentioned above, my friend had a choice for a "Superbike" kit line set which was a Y-configuration. Two lines from the master. The sales guy he spoke with told him not to bother because the brakes will be "too touchy". Perhaps that's because they'll actually bleed all the air?!?

 

Hello Walt,

Most of bleeding problems that I've run into (with brakes, not my body) were due to the master cylinder piston not being able to return far enough. This results in only a minimal amount of fluid flowing for each stroke. If there is an adjustment available, increasing the free-play results in more fluid movement, which is counter intuitive. This is because it allows the piston to move back far enough to get a fuller charge of fluid. If there is no adjustment for free-play, you can often remove the lever, because it acts as the return stop for the piston and removing it allows the piston to come out farther, and pump the piston with a drift or some other pin. This will usually move fluid fast enough to bleed the cross-over line.

 

Mike,

Thanks, I had done that too by removing the pivot bolt from the lever as this was the same issue I've had with R1s and R6s using the stock Nissin master cylinder and calipers. That also keeps some pressure in the calipes and lets the pads drag. The Brembo set up doesn't hold residual pressure and there's no drag and I've noticed that just a Brembo master with the stock Nissin calipers still leaves some brake drag.

I had speculated that air was trapped at the master cylinder banjo bolt too. But that wasn't the case either.

 

Hello Walt,

If you want to eliminate drag, try removing the anti-rattle springs, if this is possible, on your calipers. Just be sure to safety wire the pad pins. It seems like it shouldn't work but it usually does the trick.

Please, if anyone else want's to try this, be sure you know what you're doing with brakes and tools. Walt does.