On-bike camera footage of Nairo Quintana's Vuelta-ending crash has surfaced online, and though it throws some light on the situation there are still plenty of questions unanswered about what actually caused the crash.

The footage comes with a Saxo-Tinkoff badge at the start so presumably it's one of their riders, though it's not clear who from the video description. The crash happens on the right hand side of the road. Immediately before the riders fall a press moto is clearly visible in the shot; it moves out of the front of the shot and almost immediately there's the sound of braking. Next we see the moto going down on its side, just off the road, with Belkin and Cofidis riders going down with it.

However, Quintana is not there, he's a bit further down the road, probably another four or five metres on. He's clearly left the road and probably gone over the bars. An IAM Cycling rider – Jonathan Fumeaux, we think – is in the road a little further on and his bike further still. His position, and his bike's position, suggest a front wheel slide-out, possibly following a clash of wheels.

From the available footage it doesn't look the the moto caused the crash, although it does get caught up in it. Best guess would be a touch of wheels that brought down Fumeaux, leading to the chain of events further back on the road.

Quintana was stoic about the crash on twitter:

 

"Surgery in a few hours and now thinking of 2015, and the chance to pay back all the support. Onwards!" is his message, suggesting he's not fuming about his situation.