Quad Bike Racers
Built by Ralph Laughton in January 2011
This project has been giving me a lot of trouble. It is our version of the pre-war race game that incorporated governors to disengage the drive if the crank is wound too fast. Initial attempts were disappointing and after a bit of adjustment here and fiddling there, I decided that a clean start would be the best course of action. With spanner in hand the whole front end was demolished.
In order for the mechanism to work efficiently it must be free-moving and set in a very rigid frame. First, the governors were redesigned to minimise the drag on the rod. Try as I might, with lots of different combinations, it would not run freely when the drub screws in the socket coupling were tightened. If they were left a little slack I could get it to work, but prolonged use would result in the assembly shaking itself loose and the component parts becoming detached.
The new design has been prototyped and modified slightly in order to keep the whole drive mechanism in line. Angle girders have been bolted across the large flanged plate to prevent it flexing in the middle. The addition of these parts made a huge difference to the smooth running of the mechanism on the bench. I was surprised how much those large plates will distort if they are not well supported. Now it is installed on the raceway I am still having problems with the final drive distorting and yet more work will be necessary to get it running smoothly.