Brake line question.....

[13]

I notice on many factory bikes, there is one brake line coming off the master cylinder going to the right caliper, where there is a long(double) banjo bolt, bridging another line from that to the left caliper.

Most racebikes I've seen have that long banjo bolt right on the M/C, with two seperate lines for each caliper. No bridging.

Is there an advantage to this? I'm asking because I just upgraded to a brembo M/C and I don't have a double banjo bolt with the right thread. So I set it up like a stock bike, one line off the master to the right caliper, with a double off of that one and a line to the left. It rode around just fine at very low speeds, but I'd rather not boil all the fluid in my lines.

THANKS!!!

[Wishbone]

just did the same. brembo, ss lines and double banjo with pressure switch

only cost 20ish bucks for the bolt with switch, so it will be cheaper with no switch included

mabey more even pressure and better feel?

[Evil_Weasel]

i don't imagine it will effect performance much. the main reason you see race bikes with 2 seprate lines is for saftey. if you lose pressure in one of the lines you still have the other one.

[zx1012r]

If you lose pressure in one line there will be NO pressure in the other. They are not independent systems.

The only real benefit from having 2 lines from the master is bleedability (word?) They both have a nice relative straight route to the calipers, no place for air to hide. The lines that go from one caliper to the other have to go up and over the tire, creating a nice high spot where air can get trapped.

[13]

i don't imagine it will effect performance much. the main reason you see race bikes with 2 seprate lines is for saftey. if you lose pressure in one of the lines you still have the other one.

Since they both come from the same banjo bolt, you'd lose pressure in both. I got them bled fine, I just don't want wicked fading halfway into a race.

[elwood206]

I noticed the same thing on my permit class instructors busa, he seemed pretty knowledgeable and said that theres no effective difference between the two set ups, just design difference. It makes sense hydraulically that there wouldnt be a difference.

[13]

I agree. The only thing I could think of is the brake fluid from the left caliper staying hotter, because the heat has to travel to the hot right caliper to reach the "cool" M/C.

[SVRACER01]

shitcan it.. start over. one line to each caliper. that is all.

[13]

shitcan it.. start over. one line to each caliper. that is all.

Thanks for your insight. Any reason?

ANYONE WITH A DOUBLE BANJO BOLT THAT'LL FIT A BREMBO M/C?

[SVRACER01]

Thanks for your insight. Any reason?

do you see anyone else doing it?that should be reason enough. actually.. your whole L caliper being hot thing sounds like a possibility. but i stick with "do you see anyone else doing it?" theory

[smf]

do you see anyone else doing it?that should be reason enough. actually.. your whole L caliper being hot thing sounds like a possibility. but i stick with "do you see anyone else doing it?" theory

been quiet on this one, but been thinking that since you started the thread. and remember that you've been complaining about your brakes since last season. do em right . i can probably get you the banjo bolt if you run out of options, no clue what those things go for though

[13]

been quiet on this one, but been thinking that since you started the thread. and remember that you've been complaining about your brakes since last season. do em right . i can probably get you the banjo bolt if you run out of options, no clue what those things go for though

They're not expensive by any means, just not easy to find in the thread pitch I need. I'm gonna try to find one tomorrow, again. Thanks for the input, guys.

[smf]

this it? eBay Motors: BREMBO *NEW* TITANIUM MASTER BANJO BOLT (item 160104884260 end time Apr-16-07 05:34:48 PDT)

[Wishbone]

They're not expensive by any means, just not easy to find in the thread pitch I need. I'm gonna try to find one tomorrow, again. Thanks for the input, guys.

brembo has two different sizes they usually use, if all else fails talk to PK thats where i went for mine because i knew it would be correct the first time. and they should be under $20 because i spent about that for a double with the pressure switch

[JeffL]

The brake fluid doesnt actually go anywhere, does it? So the fluid sitting in one caliper usually sits right there, the fluid in another sits there, the fluid in the master cylinder is usually in that general area, and the fluid in the middle of the lines is generally in that area too. Am I not right thinking that?

[Paul_E_D]

You are correct, but the HEAT goes somewhere. By conduction it travels back up the lines.

I don't think you're gonna see major improvements on this one anyway. I'm guessing the calipers are the weak link here. Also, on a bike that old, the mounting tab on the fork is likely tweaked, reducing brake performance. Until that caliper is actually working it's best, you won't see the kind of improvement you're looking for. What was the original symptom you want to improve anyway?

[LiononaLeash]

Two independent steel braided lines gives more cooling surface area to cool the brake fluid. That's about the only thing I can think of for performance difference. Bleeding is easier I would think too, as others have kinda mentioned.

[JeffL]

Yeah, what size are those calipers? 4 pot? Cant you get away with running a beefier set of calipers if you just upgraded your M/C?

Ok, heat conduction makes sense, I just got the sense from him that it was literally a matter of fluid travel, not heat.

[13]

Nonono, it was heat dissipation I was thinking about. Paul, the only problem I had was that the factory cbr f2 M/C was pretty spongy, even after extensive bleeding. Not just that, but this nice brembo unit was given to me(read:FREE). The calipers are........damn, I forget. They're stock f2 calipers. I just purchased new HH pads and new rotors also. The M/C bled fine and the lever is rock solid now. Never felt better.

Thanks Scott! I bid on the banjo bolt. If I win, I'll change it. If not, then I won't.

[Paul_E_D]

Soundz good!

[Awesome]

Are you using stock lines? A pair of braided lines would probably make more of a difference than everything else in your system.

[13]

No, it's got braided lines. There isn't really a weak link, except for me. I just had this trick new M/C.