another example of disc brake "cuts"

[wallymann]

a friend recently got into a bit of a tangle while in a fast group ride. in the melee one guy ran into the back of another. this image shows rear tire damage when the rear guy contacted from behind. the rotors are shimano ultegra SM-RT800, not sure if they have the safety/rounded edge.

reinforces the idea that disc rotors are capable of cause injury comparable to chainrings.

[bigbill]

There's a moving chain and rotating gear teeth on the other side of that hub.

[Big Dan]

Originally Posted by bigbill

There's a moving chain and rotating gear teeth on the other side of that hub.

So, let's put more crap that can hurt you?

[bigbill]

Originally Posted by Big Dan

So, let's put more crap that can hurt you?

Mountain bikes have had them for decades. And it was a tire that got hurt because someone rode into the back of another bike. How does that relate to a person? There have been pro tour riders that were cut by discs in crashes, but more wounds are caused by pavement, fences, barriers, and the overall effects of gravity when a rider goes off course.

[Big Dan]

Originally Posted by bigbill

Mountain bikes have had them for decades. And it was a tire that got hurt because someone rode into the back of another bike. How does that relate to a person? There have been pro tour riders that were cut by discs in crashes, but more wounds are caused by pavement, fences, barriers, and the overall effects of gravity when a rider goes off course.

Ride what you like dude.
MTB's don't ride in pacelines.

[tomato coupe]

Originally Posted by wallymann

a friend recently got into a bit of a tangle while in a fast group ride. in the melee one guy ran into the back of another. this image shows rear tire damage when the rear guy contacted from behind. the rotors are shimano ultegra SM-RT800, not sure if they have the safety/rounded edge.

reinforces the idea that disc rotors are capable of cause injury comparable to chainrings.

How do you know that was caused by the brake rotor?

[FlashUNC]

Not sold.

There's a disconnect between the admittedly non scientific tests we see all around the internet and these reports from the most unreliable of witnesses: the people who have experienced crashes firsthand.

I have a hard time thinking we haven't seen mention of any prominent injuries due to rotors in, say, downhill where crashes are, it goes without saying, epic.

I'm skeptical of discs on the road generally, but I'm not sure leg safety is making those list of reasons why quite yet for me.

[bigbill]

Originally Posted by Big Dan

Ride what you like dude.
MTB's don't ride in pacelines.

If you ride into the back of another bike in a paceline, you aren't hitting the other guy's rotor. You're hitting the ground because you touched wheels. It's physics, the other guy isn't going down, you are and the other guy is rolling away. And the riders behind you with disc brakes somehow have to hit you with their brake rotor which is a smaller diameter than the wheel around it.

[Big Dan]

Originally Posted by bigbill

If you ride into the back of another bike in a paceline, you aren't hitting the other guy's rotor. You're hitting the ground because you touched wheels. It's physics, the other guy isn't going down, you are and the other guy is rolling away. And the riders behind you with disc brakes somehow have to hit you with their brake rotor which is a smaller diameter than the wheel around it.

Man some of the stuff you say doesn't even make sense.
Guess you want to win the argument to justify your purchase.
Okey buddy you win.....

[oldpotatoe]

Not sure why this is even an argument. Discs on bicycles are here to stay, for good or ill, with the 'warts' that come with them, like any bike 'gadget'...

[SlowPokePete]

Friday weirdness.

SPP

[Big Dan]

Originally Posted by oldpotatoe

Not sure why this is even an argument. Discs on bicycles are here to stay, for good or ill, with the 'warts' that come with them, like any bike 'gadget'...

Weird because as you know the top riders in the Vuelta didn't need them.

[Mark McM]

Originally Posted by bigbill

There's a moving chain and rotating gear teeth on the other side of that hub.

Except that the sprocket are too close to each other and to the spokes for a sprocket to contact the center of a tire.

Originally Posted by bigbill

If you ride into the back of another bike in a paceline, you aren't hitting the other guy's rotor. You're hitting the ground because you touched wheels. It's physics, the other guy isn't going down, you are and the other guy is rolling away. And the riders behind you with disc brakes somehow have to hit you with their brake rotor which is a smaller diameter than the wheel around it.

Are you sure about that? The OP just says the bikes got "in a tangle" and a "melee", no mention is made of whether riders went down. I've personally had contact between my front wheel the another rider's rear wheel a few times, and never gone down. Bikes can contact each in a variety of different angles and offsets. I just lined up two of my bikes, and confirmed that the front tire of one bike can indeed make contact with the rear rotor of another bike it is following.

Originally Posted by FlashUNC

I have a hard time thinking we haven't seen mention of any prominent injuries due to rotors in, say, downhill where crashes are, it goes without saying, epic.

Having witnessed many (and experienced a few) MTB crashes, I know that cyclists typically fall away from their bikes, not into them. The various accidents in which disc rotors are claimed to have caused injury involve multiple bikes, in which the injured rider fell into the rotor of another rider's bike, not into their own bike's rotor.

Originally Posted by FlashUNC

I'm skeptical of discs on the road generally, but I'm not sure leg safety is making those list of reasons why quite yet for me.

I'm actually of the same opinion. I suppose its possible that discs could present some additional safety hazards - but the situations in which those hazards come into play already present so many other dangers, that any additional dangers posed by disc brakes are marginal.