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TECH NEWS

What's going on with Shimano's wheels? Two carbon Dura-Ace wheels fold in half at Paris Roubaix

The wheels were ridden with flat tyres, exposing the carbon to the harsh cobbles... we try to dissect what might have gone wrong

Two of Jumbo-Visma’s Shimano Dura-Ace R9100 carbon rear wheels folded under their riders at Sunday’s Paris-Roubaix. The wheels were being ridden with flat tyres and showed just how harsh the cobbles can be on expensive equipment.

Punctures in Paris-Roubaix are expected and professional riders won’t think twice about continuing to ride on a flat tyre until they are able to get a new wheel from one of their team helpers.

Paris Roubaix 22 Men's Tech Gallery-10.jpg

But while this is fine, for the most part, on the smooth tarmac of a normal road race, the jagged cobbles of the Hell of the North can cause some spectacular equipment failures.

Jumbo-Visma switched from the latest Shimano Dura-Ace R9200 equipment to the older R9100 groupset and wheels for Paris-Roubaix. The reason for the change isn’t overly clear, though the rumour circulating in the start area before the race was that the team favoured the older groupset due to a number of issues with dropped chains.

Paris Roubaix 22 Men's Tech Gallery-09.jpg

The reason for the switch back to the old wheels is a little simpler. The new wheels will only accept a 12-speed cassette due to the design of the freehub. But Jumbo-Visma’s riders lined up in Compiegne on the R9100 wheels shod with 30mm tubular tyres featuring Dugast casings and Vittoria Corsa compounds.

The issue for Van Aert occurred in the Arenberg sector. It is incredibly rough and begins with a slight descent, making it particularly dangerous. Firstly, Van Aert punctured and somehow communicated the fact to his teammate Timo Roosen. The Dutch champion waited for Van Aert and it is here that we suspect Van Aert slams his back wheel into one of the protruding cobbles.

Elsewhere on the course, one of the pre-race favourites, Frenchman Christophe Laporte was having a similar issue. We would suspect the same scenario played out with a puncture to the rear tyre before the wheel failed after striking a cobble. Laporte styles it out nicely, surfing his bike before starting a long run in cleats to the end of the sector.

Laporte broken Shimano Dura-Ace R9100 wheel 2

The failures might make a case for tubeless tyres. These can be run with a foam insert inside to give a little bit of impact protection in the event of a puncture on the cobbles.

That said, this isn’t the first time that we’ve seen broken wheels at Paris-Roubaix and it certainly won’t be the last.

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12 comments

Avatar
Nick T | 2 years ago
0 likes

Shades of Shimanos wheel explosions in the 2017 Tirreno again

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timtak | 2 years ago
0 likes

I don't understand this paragraph, unless it contained something like the additions in [square brackets].
> The reason for the switch back to the old wheels is a little simpler. The new wheels will only accept a 12-speed cassette due to the design of the freehub, [and tyre sizes of up to 28mm]. But Jumbo-Visma’s riders lined up in Compiegne on the R9100 wheels shod with 30mm tubular tyres featuring Dugast casings and Vittoria Corsa compounds [/requiring the use of an 11 speed cassette(why?)].

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Griff500 replied to timtak | 2 years ago
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I suggest you go back and re-read the whole article again, slowly!  Jumbo Visma decided to run the RD9100 (11 speed) groupset, due to unclear reasons but may be due to dropped chains. They therefore had to revert to the old wheels as the newer ones don't accept 11 speed cassettes "due to the design of the freehub". Nothing hard to understand there.

The significance of tyre choice is that firstly that they were tubular, and therefore more dramatic when punctured, than the tubeless tyres opted for by many others, and secondly that Shimano only specc'ed the RD9100 wheelset to 28mm, whereas the RD9200 are specced for up to 32mm. So arguably the team were operating the old wheelset beyond spec, but what's new there! 

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Secret_squirrel replied to timtak | 2 years ago
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I think they should be 2 seperate paragraphs without the but.  Tyre choice has never had an impact on which freewheel/cassette you need. (Leaving out marginal wheel diameter changes).

"The reason for the switch back to the old wheels is a little simpler - the new wheels will only accept a 12-speed cassette due to the design of the freehub.

Jumbo-Visma’s riders lined up in Compiegne on the R9100 wheels shod with 30mm tubular tyres featuring Dugast casings and Vittoria Corsa compounds." 

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Chris Hayes | 2 years ago
0 likes

Probably a flat, then a broken spoke, then another, then another, and then a rim collapse in that order.... seriously good bike handling though! 

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Rik Mayals unde... | 2 years ago
7 likes

What do you expect when you batter a carbon wheel on cobbles with a flat? It's fucked, it's nothing to do with Shimano wheels, it's the way they are being abused.

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Drinfinity replied to Rik Mayals underpants | 2 years ago
3 likes

Depends on the wheel. Once again road racers chasing lightness over durability, in a race that is all about durability.A decent carbon MTB rim will stand up to a bit more than a few cobbles. 

https://youtu.be/VfjjiHGuHoc

 

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squidgy replied to Drinfinity | 2 years ago
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Drinfinity wrote:

Depends on the wheel. Once again road racers chasing lightness over durability, in a race that is all about durability.A decent carbon MTB rim will stand up to a bit more than a few cobbles. 

https://youtu.be/VfjjiHGuHoc

 

I thinks it's more the perceived aero benefits of the deeper rim rather than saving a few grams unnecessarily on fast and relatively flat course

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Drinfinity replied to squidgy | 2 years ago
1 like

Easy to make a strong wheel aero, especially as you have more material to play with. No excuse for stuffing up the race because of inadequate equipment. Mountain bikes solved these engineering challenges years ago, but some road racers seem determined to ignore it, even from the same manufacturer. 

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Secret_squirrel replied to Drinfinity | 2 years ago
1 like

You seem confused over 2 seperate issues. 

1.  The robustness or not of a particular manufacturers wheelset.

2.  The wheelset choice available to the the road teams.

Even if your magical MTB 29er Aero rim existed and fitted a 30mm width tolerance road race bike - it doesnt mean a particular team has access to it even if they are Shimano sponsored.

Gambles/educated guesses over robustness of equipment for a particular course vs other factors such as weight and aero are always going to be part of racing.  Its the same in every sport where equipment choices are allowed.

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Drinfinity replied to Secret_squirrel | 2 years ago
1 like

https://www.cxmagazine.com/category/cyclocross-tech/cyclocross-gear-bike-reviews/cyclocross-components-reviews/cyclocross-wheel-reviews-tubular-clincher-tubeles

What I'm confused about is why a team, sponsor, manufacturer, and fans accept equipment that is not fit for its purpose.

Even if I was DS of the "Cheese String and Spaghetti Wheel team" I would probably use some cyclocross wheels and put CSASW stickers on them. 

If I was selling wheels, I'd make efforts supply ones that didn't fail spectacularly on TV. 
 

Plenty of CX wheels available (see link).

My more general hobby horse is that on the road, even in an environment of marginal gains, we seem to resist crossover of tech from other disciplines. 

 

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Griff500 replied to Drinfinity | 2 years ago
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Drinfinity wrote:

What I'm confused about is why a team, sponsor, manufacturer, and fans accept equipment that is not fit for its purpose.

A more interesting question for me is why a team, sponsor, and manufacturer declined the option to use the latest and greatest RD9200 drivetrain and wheelset which it seems the World and his dog were waiting for, for 3 years, and why from a marketing perspective, Shimano as sponsor allowed this to happen.

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