Gatorbrake vs the rest

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Gatorbrake vs the rest
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Posted: Oct 31, 2007 at 12:54 Quote
it's called gain* scheduling i believe, and it's common in motorcycle brakes. i really wish i could remember what the proper term is, because i don't think it's gain scheduling.

the generalization of pad position is what i already addressed.

Posted: Oct 31, 2007 at 13:34 Quote
I'm looking at literature on gain scheduling and I can find nothing that's done by purely hydraulic means. Everything I can see uses actuators to boost the force and control the gain. I haven't heard of motorcycle brakes using anything but simple hydraulics (not that I'm especially familiar with the cutting-edge of motorcycle brakes), so there must be some way to accomplish it without actuators.

As I said, I do understand how smaller pistons can move before larger pistons, it's just that they don't carry any significant force with them; the first contact with the rotor will get the big ones moving until everything equalizes - and even this is a best-case scenario. It didn't take long after every overhaul of my Hope brakes for the pistons to seize one by one until only one or two of them were moving properly. They worked so much worse than a simple two-piston system.

The only benefit I've seen to multi-piston brakes on bikes is that the pistons tend to stay a tiny bit more centered. Still, the negative aspects greatly outweighed the positive ones in my experiences.

To get back to the piston motion issue, it's just simple hydraulic pressure and displacement in bike brakes. A given amount of fluid flow will cause more displacement in the smaller pistons when there's no resistance, but once resistance is encountered, displacement essentially goes to zero and it comes down to pressure, which is equal in all pistons. Sure, you can modify the ratio of friction material area to piston area to get a little variance in pressure and this should help modulation, but, again, I feel the benefits are mostly theoretical and are outweighed by the problems in implementing the system.

I'll grant you that big, heavy, and very stiff systems (ex. cars and motorcycles) tend to make better use of theory and are less affected by concessions to making parts light. Weight concerns drive bike component design more than car or motorcycle design, so we make more sacrifices in function (for a given price). Sure, people do care about weight in car and motorcycle parts, but you rarely see a 10% difference making or breaking the success of a component.

spoiledgoods,

I'll copy and paste some of our conversation for the sake of interest from others (if there is any!). It's a bit of a random jumble.

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The problem with the shim stack idea isn't the force, it's the displacement. The force at which a shim would have to pop is far less than what you'd use during hard braking (if it hadn't popped with that much force, when WOULD it pop?!); the issue is that it would have to pop after you're already applying moderate force, at which point the fluid displacement is essentially zero. You could use a spring-loaded piston (coil or magnetic)...hmm, maybe that's how purely mechanical gain indexing could be done. Yeah, if one set of pistons (out of two sets, just as an example) had the force reduced by a spring, then you'd get interesting modulation.

Well, maybe this wouldn't be of much use. We mostly have our brakes off or very, very on. Cars and motorcycles have to have a really smooth range between a gentle speed reduction down a hill and a full panic stop. That's where the super gentle initial contact can be useful. Without that spring, the initial contact of a system regulated purely by hydraulic pressure is too gentle to do anything other than attempt to centre the pistons, and we don't have as much to gain from a gentle initial contact.

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If you want power, what you actually want is a tiny lever piston pushing on a huge caliper piston. The lever piston determines the pressure (force/area, so the same force over a small area gives big pressure) and spreads it over the entire area of the piston, large or small. The catch is that it works like a lever: long levers lift heavy stuff, but not very far. High hydraulic gain moves things with lots of force (think car jacks), but not very far. Nothing's free!

Have a look at how Shimano's Servo Wave system works (only on high-end cable brake levers until the 2008 XT disc levers came out). Now THAT is brilliant. Fast movement until contact (for clearance), then slow movement upon contact (for power).

Posted: Oct 31, 2007 at 15:32 Quote
whats all the figteing abuot? guyys guys. you know im good, you know im right.
piston in lever moves what? 2 cm? in the callamper it moves mabye 4 mm on a well tunned brake. loook at the differene. the biger the piston, sure who cares. with the amount of levarge you make, and the size of the piston, it just really is finding the product that suits you best.

Posted: Oct 31, 2007 at 15:34 Quote
princeofthenorth wrote:
whats all the figteing abuot? guyys guys. you know im good, you know im right.
piston in lever moves what? 2 cm? in the callamper it moves mabye 4 mm on a well tunned brake. loook at the differene. the biger the piston, sure who cares. with the amount of levarge you make, and the size of the piston, it just really is finding the product that suits you best.

Yeah, but how do you determine that? Either test ride everything or e-fight about it until you're blue in the fingers. And we all know that's more fun.

Posted: Oct 31, 2007 at 18:30 Quote
if you got money, or a buncha spare parts, i found hayes five and juicy three caliper work good together. all i know is that its better then all hayyes 5. and all juicy three. haven't wanted to test better brbakes on the set up

Posted: Oct 31, 2007 at 18:32 Quote
some will f*ck up bad tho.. ( juicy five lever -> haynes nine calpier ) becareful, it ccann be money down the drain.

Posted: Oct 31, 2007 at 18:38 Quote
why are ya;ll making a big deal about brakes....If your using them that much you sure as hell not going fast.

Posted: Oct 31, 2007 at 19:09 Quote
r-m-r wrote:
princeofthenorth wrote:
whats all the figteing abuot? guyys guys. you know im good, you know im right.
piston in lever moves what? 2 cm? in the callamper it moves mabye 4 mm on a well tunned brake. loook at the differene. the biger the piston, sure who cares. with the amount of levarge you make, and the size of the piston, it just really is finding the product that suits you best.

Yeah, but how do you determine that? Either test ride everything or e-fight about it until you're blue in the fingers. And we all know that's more fun.


E FIGHT
ROUND 1
DING DING DING

Posted: Oct 31, 2007 at 19:10 Quote
haahahaha i think its a draw. we both make compelling arguements, and im jjust an a*sholeSmile

Posted: Nov 2, 2007 at 16:10 Quote
so the gators can match with the other brands,I think they have the nicest brake rotors off a brakes.who does not wanted gold plated Ti rotors with F1 kevlar hosePimp .I don't know if they sell those rotors as well,that would be so nicePimp

Posted: Aug 15, 2010 at 7:39 Quote
fantaman wrote:
so the gators can match with the other brands,I think they have the nicest brake rotors off a brakes.who does not wanted gold plated Ti rotors with F1 kevlar hosePimp .I don't know if they sell those rotors as well,that would be so nicePimp

I have had the 6-piston GatorBrakes for 2, maybe 3 years...
Worked GREAT for the First Year and a half or so...
I probably should replace the pads before I 'knock' them, but there is still plenty of material left and I just haven't gotten around to it...

They still work, well enough, just not the eye-bulging, lock-it-up-anytime-you-want power that they had when new...
Lever action is smooth and fine, not spongy... The slow me down okay without fear of lock-up... But, I liked them better when new...
I scuffed up the rotors to take whatever 'glaze' might have been on the pads, and they were grabby and powerful, like 'NEW' again! - slowly degrading over the next 10 rides to the 'used' status...

Again, new pads will probably fix this...
(I know... Just DO It!!!
Easy, considering, I purchased 20 pair of 6-piston GatorBrake pads for $20 - $1/pr!!!)

I have another 6-pistonGatorBrake setup for another project bike I am putting together, and Cable BB7 are the only other setup I would consider, after all the others I have used... (although the Avid Juicy 7/ultimates and Hayes Strokers and some others are definitely worthy)

I also have an 8-piston set on the way for my LenzSport ProDescender DH bike...

I will let PB know how the 8-pistons work/feel, after the first 10 rides...
Or PM me to ask any questions you may have...

P.S. They do sell the rotors separately... FINDING Them is the 'Problem'...

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