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Monotrack bike driven by an electric motor. Uses three go-kart rear wheels to guide the track which avoids lathe work making rollers from old gas cylinders etc. The build was achieved with regular tools, box section steel mainly and a budget MIG welder. I used some 90 degree pre-bent tubes for the seat mount. Shown here being ridden by Nick Thatcher, a fellow builder of strange electric projects: By keeping weight of the rider over the driven inner rearmost wheel, this grips the track OK without having to use any kind of interlocking sprocket drive with the track. Track is cut down from a large car tyre/tire. The is shown near end of the video. Small tracks from diggers and snowmobiles for example are quite expensive so for a fun project a cut-down car tyre (not my original idea) works really well at around US$45 part-worn. I found tin snips to be much better than the oscillating multi-tool I assumed would do the job. Why electric? You tend to get a lot less hassle testing in public places if your machine does not have a noisy 2-stroke engine and is practically silent in operation. You can claim moral high ground by stating with a completely straight face that this is the future i.e. an EV, whereupon most people relax, become curious and ask more about it. I had most of the parts already from the Electric Beach Luge: Why call it the Vector? Because it likes to go in straight lines (think vector graphics). I have some ideas for steering mechanism experiments. One would be to make it self balance on a smaller contact point such as the middle or rear wheel when you press a button, then steer it by leaning as you would do with a unicycle. People are asking me how you steer it, you don't! You stop and adjust your direction, maybe I should have a compass mounted on the front. Inspired by: MakeItExtreme monotrack bike with petrol moped drive system The 1939 Lehaitre tracked motorcycle Lyn Gentry Music: Motor: 24V 500Watt from golf cart. Power controller: Dimension Engineering Syren 50: Not cheap but protects itself against failure, short circuits etc so lives to fight another day if you make a mistake. At present it has been set up in the simplest potentiometer control mode (see datasheet). Twistgrip potentiometer: Magura Twist Grip Throttle 0-5K Ohm Battery: Chinese e-bike 24V 10Ah battery pack. Go-kart parts: Rear wheels and tyres x 3. One axle tube, I used 30mm diameter, cut into 3 lengths. 30mm bearings and shells x 6. Largest sprocket that will fit the tyre size a sprocket carrier. Suitable chain and 11 tooth motor drive sprocket i.e. smallest obtainable, giving maximum torque at the wheel. All bought used from web. Other: Mountain bike handlebar and centre clamp system - lowest cost ones I could find on ebay. Main power switch is emergency battery cutoff type as used in racing cars, the sort with the large red key that you twist. This key can be removed which stops small children accidentally starting it up. KISS approach i.e. Keep It Simple - Stupid ! Track tensioning system is described in the video, similar to a motorbike, moves rear wheel further backwards by turning a bolt on each side. Chain tensioning system is same concept as used on car alternators, i.e. motor hinges forwards and then clamped in position. Future mods: Speed and power are about right but battery does not last that long as the track is quite energy-sapping as would be expected. Larger battery capacity would be good. Steering system needs work. May add in some self-balancing properties.
