Buell ZTL-style brakes

[Cip]

maybe your brakes are stuffed munch; mine are flawless and 1 fingered braking is enough in all but emergency braking

[Semi]

Maybe you ride like a grandma.

[MuNch]

Mebey, i got braided lines and it stops just didn't have the stopping feel when i had my '07 ZX6.

[Semi]

I meant Cip.

[the[K]id]

Don't argue with a man who can correctly use the word orthogonal in a sentence!

Sounds like a challenge. Also, perpendicular is a less audacious term, but each to their own.

Simple, the retardation of the disc is caused by the pad, for a given system the force applied to the *swept area of disc* is simply the co of friction between pad and disc times the hydraulic force caused by the brake master and caliper system. To keep it simple, assume that force is a constant, as the distance from the point of rotation does not change caliper or pad. Force applied to a rotating object creates *torque*, torque being force times distance, the distance is the distance from the point of rotation to the swept area of the disc, so for a given braking force, the torque applied increases linearly with distance from the axle. More torque = more slowing down of the tyre. If it didn't, all super bikes would run 200mm discs to save inertia, instead of Honda increasing diameter while reducing thickness... The final part of the formula is the above in reverse, as the torque returns to a linear force retarding the wheel, so the larger the diameter of the wheel, the less effective the brakes.

Buell's system unfortunately is flawed, not in concept or design but in materials requirements, with such a small swept area and single caliper temperatures are excessive, placing a strain on road designed pads and calipers when used in even close to a track day pace. Better caliper design (ceramic plated pistons, coated pad backings, plated caliper internals), high temperature fluid (Castrol SRF or Motul RBF) and a carbon-ceramic disc would in theory make for a formidable system.

Oh, and GP bikes used feather light carbon discs, no reason to alter design to try to reduce rotating mass when it's already minimal.

Lastly, both norton and suzuki built a rotary powered bike, Mazda *bought* the rights to build rotary engines, they didn't come up with it. The problem with rotary's is not no one else makes them or one manufacture in hogging a golden egg all to themselves, but current metallurgy limits advancements in this particular engine.

[MuNch]

OH FOR THE LOVE OF GOD.

o.0

[buelllord]

maybe your brakes are stuffed munch; mine are flawless and 1 fingered braking is enough in all but emergency braking

The Buells brake is superb.

I did a brake fluid change before a track day at Collie last year and they went from good to fantastic.

If you have a judering through the lever, your disc is fucked, very common as I had mine replaced under warranty even though the bike was outside the warranty period.

[MuNch]

Thy buell lord has spoketh

[buelllord]

Thy buell lord has spoketh

Hallelujah my son

[duffman]

ahhhh yep. you had me a Shaaaaaark!
ok. there is the force providing the torque.

but Im still advocating that this torque doesnt effect the braking ability depending on how far from the axle it is.

So we agree now that there is a torque, and that for a given friction force (not clamping force) it will be greater for a larger diameter disc?

Can someone explain why a larger torque ≠ better stopping?
If I pull on the brake lever harder, then the clamping force increases, the friction force increases, the decellerating torque acting on the wheel increases, and I stop quicker.

In my mind more torque acting to slow the wheel is going to pull a bike up quicker.
However, eventually:
-there will be a point where the larger disc inertia is going to negate the benefit of the larger decellerating torque (perhaps at 330mm?)
-you will become grip limited by the front wheel
-you will go flying over the handle bars

If I'm wrong, could someone please explain why because I really don't get it.

[Barfridge]

beulllord's bike can stop in 10 feet!

[Cip]

So we agree now that there is a torque, and that for a given friction force (not clamping force) it will be greater for a larger diameter disc?

Can someone explain why a larger torque ≠ better stopping?
If I pull on the brake lever harder, then the clamping force increases, the friction force increases, the decellerating torque acting on the wheel increases, and I stop quicker.

In my mind more torque acting to slow the wheel is going to pull a bike up quicker.
However, eventually:
-there will be a point where the larger disc inertia is going to negate the benefit of the larger decellerating torque (perhaps at 330mm?)
-you will become grip limited by the front wheel
-you will go flying over the handle bars

If I'm wrong, could someone please explain why because I really don't get it.

well any good brakes can grip enough to skid the front right?

so the advantages of the buell brakes means the front wheel can be lighter so there's less rotational torque to oppose as the disk is attached to the outside rim so the force of the braking isn't transferred through the spokes. may also be brake mechanism weight losses as there's just one disk and brake pair.

[Semi]

You are right mate. I was looking at it from a conservation of energy POV and couldnt work out where the extra energy loss goes. Sussed it out now.

Biggest reason for the buells brakes is it reduces the weight of the hub and reduces unsprung weight.

[duffman]

You are right mate. I was looking at it from a conservation of energy POV and couldnt work out where the extra energy loss goes. Sussed it out now.

Biggest reason for the buells brakes is it reduces the weight of the hub and reduces unsprung weight.

Good stuff.
Thought I was missing something.

I like when these sort of things come up.
Keeps the brain active.

[Magilla]

Also, it should give you more braking control at lower speeds, because the disc is moving faster, and thus less likely to grab, when compared to the same wheel speed with smaller brakes.

[the[K]id]

Modern brakes are designed to increase consistency and 'feel', advances like mulit pad calipers (1 pad per piston in 4/6 piston calipers increases the number of leading edges, which increases initial bite, not often used on road models as initial braking can be too severe), while reducing weight. The Buell uses a much larger disc to maintain braking power (and with the latest version, a much larger caliper) while using only a single disc for reduced unsprung weight, in addition as said the perimeter mounting allows for a lighter wheel. BMW use a similar idea, where the mounting points for the brake disc are on a much larger diameter than the wheel hub, allowing material to be removed from it.

Personally, I'm just waiting for carbon-cermic hybrid discs to fall below $5000 a set, whatever way they are mounted

[MuNch]

Is this still going ????

GUESS SOOOOOOO!

lah lah lah lah

[buelllord]

beulllord's bike can stop in 10 feet!

Barfy, if you are going to have a dig, please, at least spell me correctly.