| Author | Message | ||
     Vaneo1 |
Ok heres the deal. I was looking at bicycles, and couldnt decide whether I want a road bike or a mountain bike. I just want to putt around the city on days off, but ride at least 20 miles each time I go for a bike ride (the pedal type if you havent figured it out yet). Anyway, I noticed the latest thing in brakes are bikes that sport a rotor on the front wheel. Whats up with that? In comparison to the ZTL concept, wouldnt stopping power remain greater if the pad grabbed the rim of the wheel as opposed to a small rotor? | ||
| 99buellx1 |
I have a bike with 'standard' rim brakes, and one with disk brakes. With the disk brakes, the braking seems more controlled and with better feedback. It's like you have too much braking force with the 'standard' rim brake, and the disk just feels better. | ||
| Pwnzor |
I've got discs front and rear on my mountain bike. I'll never go back to standard caliper brakes. Pinching the rim is a horrible way to stop a bike by comparison. A centrally mounted rotor on a bicycle makes more sense because you only need one and the rim would need to be a lot heavier to support a giant disc all the way around. You're only stopping about 200 pounds total, not 650. | ||
| Mikemax |
Those lightweight bike rims flex and warp causing pulsations. The disc brakes are supposed to give way more feel and stopping power. I think they can use more robust pads, too. They are really only used on Mtn. bikes so I presume they fade less; the rubber on rim brakes likely melts on a downhill run with lots of braking. And if you crash and bent the rim (it has happened to me), you have to open the calipers to continue and have no brakes with conventional rim brakes. | ||
| Ceejay |
you also gotta think what a mountain bike rim slogs through, at least in the mideast, northeast. Mud, water, and snow...putting the braking closer to the center and thus further from the mud and snow will help substantially...That and the bent rim as Mikemax stated are probably the biggest reasons they are on MB and not so much on the road ones... | ||
| Pwnzor |
You got it right. Road bike rims are also a lot more rigid than MTB rims. | ||
| Eboos |
On a bicycle, the calipers themselves have a lot of flex. Side pull calipers, V brakes and U brakes each have a lot of flex in the arms. Disk brakes are a great answer for mountain bikes due to the fact that they offer efficeant braking while putting the brake components out of harms way. For freestyle BMX, you want to be able to slip or lock the brakes at will, so a U brake setup with soft pads is usually the prefered choice. In road racing, you want to minimize weight as much as possible, so a small side pull caliper does the trick. In either of these applications, you are not stopping much more then your own body weight, so either setup will be plenty effective. | ||
| Aesquire |
?? I have to disagree. ( road rims more rigid ) Road wheels are narrower, and larger in diameter. 700c vs. 26 inch. "Aero" rims are more rigid,( "A" shaped ) than old style ( "D" shaped ) & the wheels on my Hybrid, are pretty darn good, ( Sun Aero's with 32 spoke 3 cross Scandahoovian spokes ) but not up to the bashing that current mountain bike rims are. I run old Panzer tank rims on my mountain bike. I also mass more than 230, usually. Prolonged downhill braking with rim brakes can melt the glue on sew-ups, & boost tire pressures on regular tires past the safe point, even blow them off. Would you believe a measured 50 psi increase after descending rt 21 into Naples NY? That's with a 200lb rider on a primo bike ( Stowe ) with a starting pressure of 90 psi. He kept having to brake for cars. Rim brakes also need careful adjustment of toe in on the pads, & regular cleaning of rims to maintain braking power. The seam on extruded rims can be an issue, even with machined braking surfaces. When you throw in warping, well, there is a reason ZTL brakes float. Rim brakes suck. My next bike will have discs. | ||
| Pwnzor |
Yeah, the tiny calipers on a road bike are more than sufficient. And on a BMX you definitely want U or V brakes. Disc brakes are the best thing to happen to mountain biking since forever. Finally, wet rims don't matter anymore. | ||
| Odie |
My carbon-fiber Spinergys' w/Shimano XT V-brakes do quite well actually. My technology is a little dated since I was racing XC in Germany but that XT stuff keeps on going. I have rode a disc brake for a little bit and it does feel pretty sweet though. I think you may need to look at parts prices and rebuild issues if some (when, not if) damage occurs. | ||
| Pwnzor |
I had 2 front Spinergy's come apart at the hub and swore off that type of wheel for good. Shimano Deore XT components are possibly the best components in that price range. They are so durable, rebuildable, simple, user friendly, I just can't say enough good about them. Of course, my rig is all XTR these days. I'm still running an 8 speed cassette though, that 9 speed chain is too thin for my tastes. campy gear is nice but you can get two sets of xt's for the price and they're just as good (Message edited by pwnzor on August 29, 2006) | ||
| Huxley |
I love the XT discs on my MTB, but for sheer power the nod still goes to the hydraulic rim brake. Pretty much on or off, I think trial riding is about the only place they get regular use | ||
| Rubberdown |
Brakes??? Who needs 'em. I ride a fixed gear.  | ||
| Pwnzor |
My MTB brakes are Hayes, full hydraulic set, no cables. The rest of my gear is XTR. | ||
| Daves |
Did you take the wheel and rotor off the bike, whip out your bathroom scale and weigh the difference in unsprung weight?  Sorry I couldn't resist | ||
| Pwnzor |
Rubberdown, do you ride a velodrome bike? Sweet. Do you pack your bearings or run them dry? Guy I used to ride with ran his bearings dry and put in new ones for each race. He swears by it, but it always seemed weird to me. Daves, I use a hanging scale. I can't recall how much they weigh though. I just know they are lighter than the average wheel. Ounces, less than a pound. | ||
| Rubberdown |
Just got back from a 26 mile lunch ride on the fixer. Yeah, it's basically a track bike (this one's made from an old road frame). I use plain old cartridge bearings for this bike. For track racing some guys would even remove one of the ball bearings if they had that style of bearing. These days, you can get some pretty darn good ceramic bearings for hubs if you want to spend the $. I'm not currently racing on the track and I don't need that for the road. Man, I've put thousands of miles on fixers. They will make you work your ass off going up and make you spin like a propeller going down. Coasting, shifting, brakes? ....BAH! I do have a nice road bike too.... | ||
| Court |
My MTB brakes are full hydraulic as well....course it's a Buell bicycle.  | ||
| Ducxl |
Hayes brand hydraulic disks here.I think disks are better on MTB because the rim brakes get cruddy and grind mash/w brake pads. Disks rarely get any real contact/w mud. Mountain bikes' also afford freedom when riding in city conditions of curb jumping. Kinda'....dual purpose | ||
| Eboos |
I used to use ceramic coated rims and abrasive pads. Awesome combination. This was about 10 years ago. Disks were still just coming out and were made out of unobtanium. Hayes used to market their brakes as also being made for Harleys. Did or does Hayes make Harley brakes? | ||
| Jlnance |
In comparison to the ZTL concept, wouldnt stopping power The advantage of ZTL isn't the stopping power, it's the fact that the brakes don't put any twisting forces on the spokes, and thus the spokes can be much smaller. Putting brake rotors on a bicycle will introduce twisting forces on it's spokes, but apparently they are strong enough that it doesn't matter. |
