Monday, April 28, 2014

Dan Martin's crash in Liege-Bastogne-Liege

Yesterday, full of self-loathing, I sat addicted to my laptop watching the final 45 km of Liege-Bastogne-Liege. I can't help it. I'm addicted. But the spring classics are done now, right? I'm free, right? I'll be able to resist the daily lure of the Giro, right? Sigh.

But it was an exciting finish. Caruso and Pozzovivo got a gap which looked like it might just hold... then Daniel Martin of Garmin-Sharp, last year's winner, bridged up, passing the weaker Pozzovivo and just about reaching Caruso. One more corner, then 300 meters to the repeat victory...

But amazingly, he crashed in the corner. Jonathan Vaughters, his manager, reacted:

Here's the video on YouTube.

As reported by CyclingNews, Daniel's post-race comments were:

“It’s one thing to make a mistake or know what you’ve done but we figure that there’s a patch of oil or something. I think I had tears in my eyes before I even hit the floor. There aren’t really words for it. To race for seven hours and for that to happen on the last corner…. it’s poetry.”

But was it oil on the road? In the video, there's an audible "click" right as he goes down, his inside Garmin Vector pedal down. Here's the frame from the video where everything went wrong:


His inside leg is clearly fully extended, and I don't see any indication either his front or rear wheel is out of line. It looks as if he simply tried to pedal through a corner, leaned over too far, and hit his pedal on the road.

Of course, early on the Vector was developed for Speedplay, but was later switched to Exustar due to the proprietary nature of the Speedplay design. Speedplay claims it has superior cornering clearance. Indeed, with Speedplay, the shoe will hit before the pedal. The Exustar body used on the Garmin Vector is much larger, and if you were to test without shoes, you'd conclude clipping an Exustar is much more likely than a Speedplay. But Speedplay has a lower stack height with 4-hole shoes, and thus the foot sits lower. So it's unclear if the maximum lean angle with Speedplays is actually greater. I could test, but I don't want to remove the Garmin Vectors from my bike right now, due to calibration issues. Speedplays can also be set up with short spindles, moving the shoes inward, which also contributes to lean angle.

The other contributing factor to cornering clearance are bottom bracket drop, crank length, crank "Q-factor", and tire radius. The Cervelo R5 has 68 mm drop. This is not exceptional. Dan Martin's bike is described here (from last year, but also an R5). The crank arms are photographed, but I can't tell the length. He has 25 mm tires, which help versus 23 mm tires.

So nothing here indicates he has a compromised cornering lean angle. If the pedal strike was the main thing, you wonder if the pedal choice made the difference between crashing and finishing on the podium.

For more info on the race, I recommend Inner Ring's analysis. It's probably the best site right now for pre-race and post-race reading.


specialist said...

There's a story going round that it was a publicity caravan pen?

djconnel said...

Is that a question? It would make sense: just a slight slip, increasing his lean angle, and slamming his pedal against the pavement. You've got to believe a ride like Dan Martin knows how far he can pedal in a corner. Long, long ago, before I rode Speedplay, I used to practice scraping my Time pedals at low speed, since I knew in a race there was a good chance it was going to happen, and I wanted a good feeling for how far I could go before it did.