Team Katusha Alpecin’s communications manager Philippe Maertens has posted a video on Twitter demonstrating that you can stop a fast-revolving disc brake rotor – at least one of those with non-square edges used by the professionals – with your hand.
Maertens turns the cranks of a Canyon Aeroad CF SLX, gets the rear wheel spinning fast, and then uses the palm of his hand on the edge of the disc rotor to stop the wheel without damaging his skin. He’s not putting his bodyweight or any momentum into his effort, so you could argue that it’s not a particularly realistic crash scenario.
Did the test: disc brake @tonymartin_procyclist is no knife. Or my skin is too hard… #parisnice #SRAMroad pic.twitter.com/5FykAkIPRE
— Philippe Maertens (@philmaertens) March 6, 2017
This follows on from Tom Boonen’s claim last week that he (and anyone else) can stop a disc fast-spinning brake rotor with his hand.
“I maintain that they are not dangerous,” said Boonen. I’ve dared to stop a wheel at 60 kilometres an hour with my hand.”
Several pros, including Team Sky’s Owain Doull, have raised safety concerns about the introduction of disc brakes.
We conducted our own not-entirely-serious research which you can watch here.

























10 thoughts on “Video: Man from Katusha says disc brakes don’t cut your skin”
Given the team history, yes,
Given the team history, yes, maybe you are thick-skinned.
Before people claim this
Before people claim this ‘wasn’t a race scenario’, let’s compare apples with apples then: time for a disc-downer to demonstrate how safe inserting your hand into a typical bladed-spoke wheel at a similar simulated speed is.
Away you go.
KiwiMike wrote:
Or catching a falling bike by the cassette or chainrings.
Dont try this at home, you
Dont try this at home, you will be fetching your fingers from the gutter!
Safe to say I wont be trying
Safe to say I wont be trying that with my hope saw blade discs
Despite not following the
Despite not following the disc brake chainsaw brigade I’m quite surprised he didn’t et some sort of injury from this, even if it was just a bit of a graze.
i wouldn’t have been brave enough to try it.
Who’s going to try the same
Who’s going to try the same on a bike with disc brakes after an alpine descent?
(No subject)
I may be missing something
I may be missing something here, but surely a bigger risk of injury from a disc is if you hit it at speed? The sustained friction scenario is possible, no doubt, but if you are flying through the air and then your knee strikes against a moving or static disc at say 40mph, then any injury would be entirely different to the friction type injuries being debated.
I’m neither pro nor anti, although I am still not sure that there should be a mix of rims and discs in a race.
“Man from Katasha says”
“Man from Katasha says” sounds like something Jeremy Clarkson would say as a joke in Top Gear, try reading it in his voice, and you’ll agree.