Outsider Bais wins Giro stage on snow-capped Apennine peak
Andreas Leknessund retained the overall lead against expectations on a testing and relentless climb above the treeline after which there was no change in the general classification.
Leknessund leads ahead of favourite Remco Evenepoel and Aurelien Paret-Peintre, while Damiano Caruso and Joao Almeida kept pace and Ineos pair Geraint Thomas and Tao Geoghegan Hart failed to launch an expected attack.
"The conditions weren't right we were put off by the head wind," said Thomas.
The Norwegian overall leader Leknessund went as far as describing the stage as boring.
"It was only full gas in the last kilometre. I can be grateful for that and have some more days in pink," Leknessund said at the line.
"I was expecting it to be harder. It was also quite boring, I'd say. I was looking forward to fighting, but of course I'm happy and grateful."
The 23-year-old Evenepoel, of the Soudal Quick-Step team, skipped effortlessly away from a weary peloton over the final few hundred metres on the Grand Sasso (Big Rock) to finish fourth on the day, with 33-year-old Jumbo leader Primoz Roglic appearing equally at ease following him over the finish line in fifth place at over 2100m altitude.
For the little known 25-year-old journeyman Bais this was a first top-level win and came after he escaped early targeting some mountain points.
He did not expect to finish the day picking up the stage win or the king of the mountains jersey, but can now dine out on both of them.
"I only went in the break to pick-up some mountains points, I still can't understand what I've done. This is my first pro win and it's incredible," he said, dedicating the win to his family and team, EOLO-Kometa, which has former climb kings Alberto Contador and Ivan Basso in management roles.
Fellow escapee Czech rider Karel Vacek came second, nine seconds off the pace, and another Italian Simone Petilli finished third.
Saturday's stage eight is on rolling terrain while on Sunday Filippo Ganna of Italy will be co-favourite with Evenpoel in a blockbuster 35km individual time trial.