Another pro disc brake crash

[kramnnim]

Funny how his shoe was so close to the spokes but didn't get chopped up.

[lhuerta]

Originally Posted by ceolwulf

I think this is reasonably solid evidence ...

http://www.velonews.com/2017/02/vide...lly-cut_431182

Pretty clear that those rounded rotors are unlikely to be the culprit here.

Ohhh Caleb from VeloSnooze u should be fired for this sort of non scientific testing . A rotor need not be spinning in order to cause damage. The bigger culprit is the heat from braking. The accident today occurred as the peloton was revving up for a sprint. If we conservatively estimate they were rolling at about 35 mph, a sudden stop to avoid a crash might be enough to heat up the rotor, which upon contact with anything, even w/out rotation, might be sufficient to cause some damage on whatever it contacts. Duh?

[572cv]

Looking at this from 10,000 ft, it would seem that while there appears to be a chance that riders can be hurt by disc brakes, it would also be the likelihood that disc brake effectiveness could generally improve safety in the peloton, on downhills, in wet weather at the least. So, the question becomes, what is the incidence of each? What is the tolerance for the increased incidence (presumed) of injury from disc brakes, in the face of a decrease in injury from falls on downhills, particularly wet ones?

In WW1, there was a standardization and improvement of helmet design. One effect was that there was a substantial increase in hospitalization for head injuries. Some generals complained! But the reason there were so many more head injuries was that soldiers were surviving. They didn't just die. The helmets worked. The whole exercise was an improvement. It just took a while for people to realize that was the case.

I actually don't like discs on my bikes, because they seem to require more attention to maintain tolerances, and my requirements are no longer race level. I love the minimotos on my new Eriksen. But in the pro peloton, they've got wrenches checking brakes every day. I will wait to see what the balance of favorable and unfavorable settles on over a reasonable time period. That will determine whether discs are accepted for the long term by the pros.

[ColonelJLloyd]

Originally Posted by lhuerta

A rotor need not be spinning in order to cause damage. The bigger culprit is the heat from braking. The accident today occurred as the peloton was revving up for a sprint. If we conservatively estimate they were rolling at about 35 mph, a sudden stop to avoid a crash might be enough to heat up the rotor, which upon contact with anything, even w/out rotation, might be sufficient to cause some damage on whatever it contacts. Duh?

Do you ride a bike with disc brakes?

[nate2351]

Originally Posted by lhuerta

Ohhh Caleb from VeloSnooze u should be fired for this sort of non scientific testing . A rotor need not be spinning in order to cause damage. The bigger culprit is the heat from braking. The accident today occurred as the peloton was revving up for a sprint. If we conservatively estimate they were rolling at about 35 mph, a sudden stop to avoid a crash might be enough to heat up the rotor, which upon contact with anything, even w/out rotation, might be sufficient to cause some damage on whatever it contacts. Duh?

I was frustrated with this video as well but for different reasons. In no way does this take into account the momentum a rider carries into the rotor. You can spin a wheel up to 50mph in the stand and shove a wrench in it and only pop a few spokes. But when you have a rider on there, even at a much more realistic 25 mph, you could pop a half the wheel. I've gotten up from numerous wreck to see wheels with half the spokes on one side broken.

[kramnnim]

Better test would be to have a rider pedaling a bike on a trainer, and pressing the shoes and saddle into the rotor as he continues to pedal. Probably have the same results.

But, hey, people know who Owain Doull is now!

[Dead Man]

What you get for not having custom carbon shoes.

[batman1425]

I have a seriously hard time buying this. IMO the overhead footage shows that he and the rotors in question are going in pretty different directions after he initiated the crash.

The evidence after the fact on his shoe is interesting, I'll give him that, but one could argue he clipped some sharp edge of the barrier that he plowed into, perhaps an exposed screw or nail, or just a thin hard edge of metal rather than a red hot spinning blade of death.

I also find it interesting that some anti-disc pros are quick to jump on any possible injury that could be related to a disc brake and blast the propaganda. How many injuries or equipment damage like this happens in the non-disc peloton that we never hear about, its just "what happens in a crash"? I don't know the answer to that, but in some ways I feel like the apparent short fuse to blame discs in a crash is in a way, some riders way of rebelling against their integration into road racing.

[dgauthier]

Originally Posted by nate2351

I was frustrated with this video as well but for different reasons. In no way does this take into account the momentum a rider carries into the rotor. (...)

Absolutely. The whole test is laughably timid. In addition to driving the wheel with the momentum of a rider, he should try to jam the shoe into the rotor hard enough to damage the rotor and frame.

A lot of unanticipated and unintuitive things happen during a real crash because of the tremendous forces involved. Who could guess handlebar end plugs exist for one purpose: to keep the handlebar from punching a hole in you during a crash. If one had never seen a handlebar injury before it would be very difficult to even imagine, let alone duplicate it on a test bench.

If only all bicycle crashes were as gentle as what is shown in that video.

[oldpotatoe]

I'll add it here too

http://www.cyclingnews.com/news/marc...abu-dhabi-tour

and

http://www.cyclingnews.com/news/chri...ot-being-heard

wonder if it's more about 'being heard' than disc brakes..

[smontanaro]

Originally Posted by tuscanyswe

They are still only a couple of millimeters thick and spin pretty fast regardless of rounded edge.

Plus with the motor, it just spins like a meat saw.

[batman1425]

Originally Posted by oldpotatoe

I'll add it here too

http://www.cyclingnews.com/news/marc...abu-dhabi-tour

and

http://www.cyclingnews.com/news/chri...ot-being-heard

wonder if it's more about 'being heard' than disc brakes..

Honestly, I think that is exactly what is happening. There is a sizable contingent of the peloton that is against disc brakes and creating (for lack of a better word) a high profile negative outcome is one way to get the powers that be to slow or reverse the transition and consider other paths that improve rider safety. It's a powerful tool for a contingent of people that don't feel like they are being listened to regarding rider safety. I completely get it, the riders want to be safe, and I'm not suggesting they are fabricating anything, but the potential for bias is high and riders seem to be quick on the trigger to blame discs.

[rileystylee]

yawn

[ultraman6970]

As long as sponsors are paying I doubt thie equipment will be off. The cutting issue is still at debate till real probes comes up (if there's any already), but the second big problems with disc is going to start now, which for me is a lot more easy to spot on and maybe even more important.

In the classics a slow change of wheel can get a rider off the race quite quick, and Im just waiting to see what is going to happen in the next weekends. Just one or two fav with discs losing a race due to a wheel change and I doubt we wlll see discs too often this season.

[drewskey]

I'll armchair here too! Put on the tin foil hat.

""That’s why the crash happened, because we got stuck with our handlebars," Kittel said."

Well that doesn't seem correct.

Watch this

At 0:26, you see Kittel push/elbow/whatever you want to call it Owain, who gets pushed into Ewen who goes into the barrier legs,

Per the steephill video, Owain doesn't unlclip into Kittel's bike. His left foot never crosses his bike as he is falling TO HIS LEFT.

What we do see in the linked video is a sharp metallic object that has rust; the barrier feet.

So in summary I believe that Kittel was at least partially to blame for his own accident and Owain's shoe got cut by the rusty barrier.