They must have really smooth roads in the Tour De France. That snap on plastic covers will simply fly off the bike once the they start going over cobbles or poor road. I wonder how much weight they add to the bike? To think the developer spent money on a lawyer in getting the device patented.

I wonder if they took the wheels for wind tunnel testing to see how they would fair in cross winds?

Its for You nervous Tifosi , the Pros already solved the problem by staying with what worked fine for a century or more ..
UCI did a safety withdrawal of permission ..

But You are free to make your Own shopping Choices, since you dont have, or need a UCI Race Licence .


The real development has been in the high end Mountain Bike sector of the market ..

Sorry, but this just isnt' true. The endo limit has nothing to do with tire friction. REALLY lousy tires (I'm not sure any that bad exist but I've never ridden knobbies) or poor road surface (dusty/wet etc) or obviously a combination, can prevent you from even being able to reach the endo limit... but in that case what happens is your tire slides before it can endo. That could either save your life or end it, but anyway, you wont endo.

In other words doing an endo requires enough traction to stop fast enough to do an endo, easily achieved on dry pavement. No awesome tires are going to increase the endo limit though.

I'm not sure your point. The endo limit isn't a notion. It's what throws your head into a lamp post. You cannot stop faster, regardless of notation. (until you hit the lamp post)

But, but, but,... Technically speaking, rim brakes are a form of disc brake. the rim is the outside of the disc and the brake blocks are the pads. LOL

Cheers

And it should be fairly obvious that cars (even most SUV's) have a MUCH higher endo limit, allowing one to take advantage of much higher deceleration rates. They also have MUCH more mass meaning the force required to reach 0.6 g, F= m*0.6g is MUCH larger. There is no comparisson. For cars the absolute limit in ideal conditions absolutely is the tire friction, which is closer to 1g than 0.6 g in good tires.


The argument there though also isn't about increased stopping force. It's about better control and better fade etc. Like I said, I'm open to that kind of argument, but just saying "they work better on cars" is a silly diversion. It's an entirely different situation. Cars don't even have rim brakes to compare to.

I understand this argument from a physics perspective. However: https://www.youtube.com/watch?v=uHFSSXOSnxs This test found there to be a measurable difference in braking distance. Even on dry. I suppose I like physics, but I like engineering as well.

Second point, original topic: I don't get why you'd want to cover the rotors with anything. Why not have the very tip of the rotor be wider, and quite blunt? Say, the last 5mm of the rotor is 2x the width, with a rounded profile to it. Yea, you'd have to remake the brake itself to accommodate this design to clear that bulge, but that seems way better than putting a silly shroud over the whole thing. And at least the cooling should be better (with the increased surface area), and not worse. Aero would suffer, but only very mildly.

I like Hayes Disc Rotors

Yes, you're correct about this -- I typed before I thought.

While not exactly scientific or even clearly unbiased, I actually do think that video seems to make a balanced presentation. I did say earlier that rim brakes will have a delayed onset in the wet and that seems to be the biggest effect that they find. Slightly better modulation might be an issue too, but I'm not exactly convinced on that.

What would really be the end all of brakes is a sort of anti-endo. Like a spring loaded cable feedback from the rear suspension that limits front brake power as the back wheel lifts off, so that you really could confidently apply right up to the endo limit. Comparissons of two riders on dry surface is largely up to their skill, confidence, and nerve in being willing and able to go right up to that limit. You can get some feedback by way of the using the rear brake simultaneously with the front, and sensing lock up in the rear, but I think the feedback loop for that process is still too slow.

The UCI is resuming the use of discs for selected races later this year, with a requirement of rounded edges on the discs, as well as evaluating other updates including guards and circular outer rims on discs.

I can't believe that the concept of a guard could be patented, at least not broadly. One might be able to patent a narrow device so that one couldn't simply mold knockoffs. Maybe the mount?

The guard should not negatively affect cooling of the disc. Should not be susceptible to heat of the disc. And also has to stay in place during a 30 MPH crash.

I'm a bit surprised to see it attaching to the wheel and not to the frame. Retrofitting? A through axle might help with front wheel retention, but shouldn't be needed on the rear.

When it comes to the UCI, if there was a group like them in charge of autos, cars would still have hand cranks, carbs, manual trannies, and only come in black.

When I say locking the front wheel, or any wheel, I mean that you stop the wheel from rotating. If you're going 20mph (or any relatively fast speed on a bike) and squeeze the front brake hard enough, that wheel will stop, it probably won't skid, and if enertia works, you'll probably go over the bars or close to it.

Locking the wheel can result in skid, but it doesn't have to. I can be standing still and lock a wheel by squeezing the brake and not letting it spin.

Anyway, this is silly and we're arguing over nothing. I was just giving you a little **** for saying you couldn't lock the front wheel. I didn't really mean for it to turn into a scientific discussion. It's all good.

yeah uh sure you can, it doesnt even require any skill

you may be flung , face-planting your self on the pavement locking up your front wheel, if you want that.

The front wheel coming out of the fork, by hitting the disc brake with a loose QR Skewer is also effective.

I'm so concerned about stopping my 190 pounds of vehicle+rider, going 20 MPH, that I think I will give up cycling until they adapt locomotive brakes to bicycles. I really need microscopically sensitive modulation and the power to render my <1" wide tire immovable by just brushing some kind of control with my pinky; and I'm so tired of seeing the crippled and lifeless millions who have suffered as a result of inadequate bicycle brakes over the last hundred years! I mean, C'mon.....this is serious stuff; we're not talking about children's toys here!

And my goodness, the rim wear from caliper brakes! I mean, I just know, in the next few decades before I croak, I may wear-out a rim from those nasty brake pads rubbing the sides of it! It could happen!

You need to ride more if it will take you that long to wear out rims!

I posted this in another thread recently. I just a new bike with discs. I tested stopping using it and two other bikes I have with rim brakes, one with Kool Stop pads and the other. I did it multiple times with each bike going 15 mph. All three stopped about the same. I then rode each bike through water the the discs stopped a slightly better. When I quickly touched the rim brakes to clear wAter and en hit the hard, the differences again were minimal.

I don't doubt the benefits of heat on steep mountain descents or constantly heavy rain. But for most riding, it's not worth it.

Hydraulic or cable disc?

Hydraulic

OK,
The guys at GCN had a little better results with hyd.

https://www.youtube.com/watch?v=uHFSSXOSnxs

Rim brakes, excessive heat, and long descents aren't good for carbon wheels, have even seen them taco in the Tour of Oman last year. (around the 1:15 mark)

That said, rotors can also get hot and pads can give out.

That's interesting. Thanks for posting.

They didn't do a test on good roads with wet conditions. That's what I did. The best I got was five feet better with disc. The other times were a couple feet at most. But I was was going 15 mph and they were doing 25

Disk brakes are not so advantageous to pro riders but are very useful for the rest of us and that should be OK. Anyone commuting all-weather on a road bike should consider disk brakes; they stop the same as rims in the dry and the same as dry rims in the wet.
A lot of disk roadbikes are starting to use chainstay position, which frees up the rack and mudguard mounts, then omit these mounts. The cable routing of disk brakes is not optimised for chainstay mounting, exiting at the wrong angle. If manufacturers changed the direction of rotation and exit from the bottom of the roller, the cable run would be more effective.