Here is a nice collection of photographs from the National Archives covering a hill climb event on April 5, 1940. I've included the original photographer's notes which provide a good description of each photo.
At the start of the course. The going gets even rougher and steeper further on. The crowd in the background is composed almost entirely of young fellows. At the bottom of the hill can be seen the parking area. Besides the automobiles, approximately 200 motorcyclists had come to this Sunday event.
His first hill climb. The fellow on the left is fixing the gear shift for him while the other is explaining how to take the bumps. The man with the goggles is wearing a shirt of a local motorcycle club.
Breaking the starting tape.
About 18 years old, and one of the most daring motorcycle riders at the meet. He wears his own name on his sweater, and has a crash helmet fitted over his regular leather helmet. Crash helmets are made of steel or a composition of Balsa wood lining.
This contestant watches another attempt the climb. He wears a sweater which bears his motorcycle's trade name.
This young motorcycle enthusiast is a contestant in the meet.
On the way to the hill climb, this motorcycle party stopped by the roadside while one of the motorcycles was repaired. The girls were pillion seat riders.
An apprehensive onlooker. This woman is a motorcycle enthusiast and was among a group which came by way of motorcycle to the hill climb.