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From soft vegetables to meat products and footwear, we spin up the blades of doom

So, disc brakes are big in the news again, with Owain Doull claiming that one nearly took his foot off (sort of) in Abu Dhabi. Anyway, we've been here before, and there's plenty of people claiming that the blades of doom will be amputating limbs at will, with others offering the counter view that you couldn't cut yourself out of a wet paper bag with one.

Disc brake testing: the subjects

Disc brake testing: the subjects

Anyway, there's nothing like a couple of beers of a Friday to make us amenable to a bit of unrigorous scientific testing. And so earlier we were on facebook live offering up various meat and vegetable products to the Ice-Tec rotor of Tony's rear wheel, ably powered by Liam the intern. Cucumbers, carrots, bananas and chorizo were sacrificed to the rotor, plus a bit of pork belly so we didn't have to use our own flesh. It's quite a middle class selection. But the office is next door to Sainsbury's. At the end we also gave it a shoe to eat, to see if we could replicate Doull's predicament. Now we've stuck the vid up on Youtube too, so here it is in all its unrehearsed glory. Enjoy!

DISCLAIMER: if you're looking for peer-reviewed science or Pulitzer-winning investigative journalism, you've come to the wrong story.

Dave is a founding father of road.cc and responsible for kicking the server when it breaks. In a previous life he was a graphic designer but he's also a three-time Mountain Bike Bog Snorkelling world champion, and remains unbeaten through the bog. Dave rides all sorts of bikes but tends to prefer metal ones. He's getting old is why.

23 comments

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frogg [87 posts] 4 months ago
2 likes

Just a few days ago on hackaday ... pretty sharp eh

http://hackaday.com/2017/02/14/knives-hewn-from-brake-discs-past/

 

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hsiaolc [343 posts] 4 months ago
2 likes

Excellent test.

Well done. 

We should ban spokes first before discs. 

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GavinT [82 posts] 4 months ago
0 likes

Damn that made me nervous! Fingers that close to moving parts, gloves or otherwise...you're a braver man than me!

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The _Kaner [1075 posts] 4 months ago
6 likes

Well, I for one, hope that they ban chorizo and cucumber from the peloton.

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Disfunctional_T... [173 posts] 4 months ago
0 likes

The rotor in the video is not rounded. They should do the video over with a rounded rotor.

The cucumber in the spokes was hilarious.

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Ogi [100 posts] 4 months ago
0 likes

Legends  1

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pockstone [98 posts] 4 months ago
1 like

Who'd be a bloody intern?!! I hope at least he got to take the results home to make a nice casserole. I think you should perhaps have used a control to validate your results:

 

 

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Tony Farrelly [2893 posts] 4 months ago
1 like

pockstone wrote:

Who'd be a bloody intern?!! I hope at least he got to take the results home to make a nice casserole. I think you should perhaps have used a control to validate your results:

 

 

We did offer I even rinsed off the pork (technical term) but he said he didn't have any room in his bag…

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ashliejay [47 posts] 4 months ago
2 likes

going by this extensive scientific experimentation, roadies need to toughen up, and stop crying at everything new.

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gnarlyrider [28 posts] 4 months ago
2 likes

Try adding 30 mph impact to the test to simulate the impact of a moving rider onto  a stationary but spinning disc, or vice versa 30mph spinning disc hitting stationary cyclist.  Not certain about  the sharpness of the disc but the speed of impact will have a major effect. It works well for fruit with a bill hook.  

See video 

https://www.youtube.com/watch?v=LUgQ-g2nwCE

from 3:10 onwards to see effect of moving blade (disc) on stationary rider - watermelon or pineapple

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gnarlyrider [28 posts] 4 months ago
0 likes

the next video is instructive! 

https://www.youtube.com/watch?v=IaImt71B5BY

spinning blade (a little bit fast!) and moving fruit but is show the effect of speed of impact with a bluntish blade.

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Redvee [321 posts] 4 months ago
5 likes

Cutting edge journalism  3

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beezus fufoon [673 posts] 4 months ago
3 likes

suitably homo-erotic, all you need is an overweight nurse and you can remake some carry on films!

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hugheke [10 posts] 4 months ago
1 like
Tony Farrelly wrote:
pockstone wrote:

Who'd be a bloody intern?!! I hope at least he got to take the results home to make a nice casserole. I think you should perhaps have used a control to validate your results:

 

 

We did offer I even rinsed off the pork (technical term) but he said he didn't have any room in his bag…

ooh er missus!....

 

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Yorkshire wallet [1077 posts] 4 months ago
3 likes

Well what we've all learned is keep your cucumber covered whilst racing.

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SuperG [118 posts] 4 months ago
0 likes

I'm amazed any mtb riders are still around (they are pobably without their cucumbers or chorizo's tho!), discs have been used in down hill, XC and more recently cross.

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Boss Hogg [86 posts] 4 months ago
1 like
frogg wrote:

Just a few days ago on hackaday ... pretty sharp eh

http://hackaday.com/2017/02/14/knives-hewn-from-brake-discs-past/

 

Send one to Doull with compliments! ahahhaaahhhaah

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LarryDavidJr [347 posts] 4 months ago
0 likes

Why are MY Fridays at work not like this?

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frogg [87 posts] 4 months ago
0 likes
Boss Hogg wrote:
frogg wrote:

Just a few days ago on hackaday ... pretty sharp eh

http://hackaday.com/2017/02/14/knives-hewn-from-brake-discs-past/

 

Send one to Doull with compliments! ahahhaaahhhaah

excellent, then he would have a real reason to complain ...

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Prosper0 [92 posts] 4 months ago
0 likes

So yes. Basically. Shock result, disk brakes do indeed have the ability to cut on contact. 

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velo-nh [105 posts] 4 months ago
1 like
Yorkshire wallet wrote:

Well what we've all learned is keep your cucumber covered whilst racing.

 

But think of the grams you'd save.

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kie7077 [904 posts] 4 months ago
0 likes
Prosper0 wrote:

So yes. Basically. Shock result, disk brakes do indeed have the ability to cut on contact. 

Yes, if you're a giant carrot riding a bike.

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anders.r.soderback [20 posts] 4 months ago
0 likes

Sure interesting... And funny  4  Next time I would love to see you road.cc guys do a more thorough test with a rotor that is hot after the brakes are applied. So do this the next time:

1. 30mph+ riding

2. Apply brakes

3. Then get your fresh meat out to the spinning rotor

 

I am not saying that this will be more "cutting edge". I am saying that it would be interesting to see if it is. Because this is what a real live test would look like.