Turn a corner on a bicycle, and you lean instinctively, so that weight and centrifugal force combine along the line of the bicycle. It's different on a tricycle. There is normally no way to lean, and the centrifugal forces must be resisted by wheels and frame, which must be made strong and heavy. Small wheels are needed to resist the sideways forces, although larger wheels make for a more comfortable, easy-rolling ride. The riding position must be kept as low as possible to prevent overturning on corners, although a higher riding position would be more pleasant in traffic.
To overcome all of these problems, you need a leaning tricycle - but this is a vehicle whose design presents formidable technical challenges. The Tripendo's solution is an ingenious parallelogram linkage, dual-wishbone suspension system which gives an intuitive, stable and comfortable ride. Rider, frame, and all three wheels lean in parallel by up to 26º, controlled by the right-hand control lever. The left-hand lever controls the steering angle of the front wheels. The combination of these two motions compensates for any corner at any speed. Centre-point steering gives predictable handling, even on rough surfaces.
It's also tremendous fun. The steering takes just a few minutes to get used to. You only really use one control lever, the other just being used for small corrections. Once you've mastered it, it's a blast! You can power through corners which would otherwise require serious acrobatics on a non-leaning trike, and there's no worry, as there is on a bike, that a wheel will break loose and dump you.
The 'Standard' Tripendo has a fibreglass frame, a V-brake on the rear wheel and hydraulic-operated Sachs drums at the front. The 29kg carbon-fibre 'Carbon' version uses Formula disk brakes. Both feature swing-arm rear suspension. A good fit is achieved by sliding the bottom bracket, and an internal tensioner means that you don't need to adjust the chain length. The chain is kept away from the rider's clothing. Two frame-sizes fit riders between 1.60 and 1.95m tall. The 26" (559) wheels (spoked or carbon fibre) are driven by a 24-speed transmission, controlled by an EGS Synchro-Shift. A Rohloff 14-speed hub gear is also available, as is an electric power-assist unit.
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