The Build
Super Subs
Super Subs' expert Jonathan suggested the team use a combination of bikes and 4x4 car to make their pedal-powered locomotive. The bikes will turn a shaft that turns the defunct engine, sending drive to the wheels. This should give them a huge choice of gears and good grip from four powered wheels.
They weren't too successful on the scavenge though. For a long time all they had to show for their efforts was a shaft and some sorry looking bits of bikes.
When the boys finally found mountain bikes and a Land Rover things took a turn for the better. Expert Jonathan dove into the Landy engine, taking out the pistons so it would be easier to turn over and fitting a sprocket to take the power from the rolling road.
The team wanted a Land Rover because they'd seen them adapted for driving on rails before and they were supposedly a perfect fit. But their model was a long wheelbase version and they had to waste valuable time adjusting the wheels to make sure they didn't fall in between the track.
When they ran the Land Rover's engine, it turned in a clockwise direction so the Subs set their bikes to rotate in the same way. But because the rolling road reverses that direction, it turned the engine backwards. So to use the Landy's eight forward gears they would have to race backwards! It wasn't pretty but it worked and they finished ahead of time, justly proud of their efforts.
Sweet Chariots
Ben pitched a wild idea to build a giant hamster wheel locomotive. The team would run in the wheel, turning the rear wheel of a motorbike that would then send drive to the wheels of a supporting chassis. The Sweet Chariots were struck dumb by the idea but decided to go with it, realising they'd be able to utilize their weight and scrum practice.
Their build started well, with scavengers Jay and Paul swiftly finding girders from a Nissan hut (which would form the circular sides of their hamster wheel) and a massive collection of chain, sprockets and mesh. But once everything was back in the workshop the team began to flounder, overawed by the scale of the design and sheer amount of welding needed.
It took much too long to make up the giant wheel, which meant the mounting of the motorbike to butt up to the larger wheel became a real bodge job, not helped by the team's ability to talk about the problems rather than cracking on. With the motorbike mounted but with little of the chain and sprocket drive to the rail wheels complete, time ticked away. They faced a very busy tinker time.
