Originally Posted by GeorgeL

IIRC, he had removed the cap and was jiggling the bike to judge the level. Having done that many times myself the actions seemed pretty natural.

Motorcycle scene- The Great Escape, 1963, Steve McQueen - YouTube

Of course, the motorcycle was a '62 Triumph Trophy, not exactly standard issue in the Wehrmacht.

There are some spots in the chase where you can see McQueen, hidden by goggles and a German uniform, apparently chasing himself!