Jack recalled a curly frame that he had seen on a stand at the Lightweight Cycle Exhibition at the Floral Hall. It had been made by Maurice Selbach who had said it was just a fancy idea. Not to Jack it wasn't! If the front forks curve to absorb road shocks, he thought, then why shouldn't I try to do the same thing with the rear stays?
He built his first frame with a gentle curve in the seat stays and the 'S' bend in the chain stays. The idea worked, the bends did damp the road shocks, but there was an unexpected benefit. The 'S' removed a great deal of the flexing of the bottom bracket zone.
The frame was given to one of the hard men of cycling to try, Harry Rothwell. In order to toughen himself and to test the frame thoroughly, Harry carried two house bricks in his saddle bag.
...
The development work was now completed and in 1932 [sic -- should be 1934] the Rear Vibrant Triangle (patent No 33317) and the Hetchins Vibrant Triangle (Patent No 443454) were taken out. The curly Hetchins was born. [There were not two patents, as O'Neill here suggests, but only one. --Editor]