Porte, Chris Froome (Sky), and Bauke Mollema (Trek-Segafredo) had attacked from the General Classification group and held a 23-second lead when the incident took place.
“The crowd was all over the road and the motorbike just stopped right in front of us and we had nowhere to go but straight over the top of the motorbike,” said Porte immediately after the stage.
“It was just a mess. Froome was on my wheel and was straight into me. I don’t know what they’re going to do but they need to do something about it. It’s not fair. One minute we’re 23 seconds in front and the next thing for something so silly, everyone’s back on us.”
The crash caused Porte to require a wheel change which saw him finish more 45 seconds back on his General Classification rivals. Team-mate Tejay van Garderen was also caught up behind the crash when the group was forced to slow behind the stationery motorbike.
“That can’t stand, it can’t happen like that,” said Porte. “Surely the jury has to look at it and use some sort of discretion. If you can’t control the crowds what can you control?
“It’s not really the motorbikes, it’s the crowds in your face the whole time, pushing riders. At the top there it was just crazy.”
After the stage finish, the UCI jury awarded Porte and Froome the same time as Mollema, who finished five minutes and five seconds behind stage winner Thomas De Gendt (Lotto-Soudal). This sees Froome hold on to the overall lead, as Porte and van Garderen move into seventh and eleventh overall.
“It’s the decision they had to take,” said Porte.
“It’s already out of control. I agree that you come to the race, you have a good time but you don’t need to be running beside the riders, you don’t need to hitting riders, pushing riders.
“Things have got to change and I can’t believe there weren’t barriers there. At the end of the day I’ve trained so hard for this and yeah okay now I get the same time as Mollema, but I also crashed and now I’m sore,” he said, before turning his attention to the Stage 13 time trial.
“Tomorrow’s a crucial stage as well and it remains to be seen how I’ll pull up. It’s bitterly disappointing but at the end of the day it’s the right decision by the UCI jury,” said Porte.
“We love the fans and 99 per cent of them are brilliant but why do some of them need to take their selfies and run along beside us? There’s passion and there’s stupidity and it’s not such a fine line between them.”
“It’s a fair decision for all parties,” echoed said BMC team principal, Jim Ochowicz.
“I don’t know how else you could resolve it other than go back to the one kilometre mark and take the time from the riders at that point. But there could have been more time gaps one way or another had they gone to the finish line without the crash. But under the circumstances it’s fair for everybody.”
Porte will be examined for any injuries by BMC Racing Team’s medical team and further updates on his condition will be provided when possible.