I have a new eGo cycle2 and I was curious if it is possible to construct a device with a switch that will allow temporary speed/power increase? I know little of electrical engineering, but I can pick up what I need to if someone is willing to help. There is room for more batteries, so could those be activated with a higher voltage running through the system? Will I really achieve higher top speed without changing the gear out to something bigger?
You can achieve a higher top speed without changing the gearing with a voltage increase. The issue is how fast do you want to go, and for how long? Can the motor take it? How hot is the motor getting now when riding?
The switch you speak of is definitely possible. The way I would do this is a switch that powers a large contactor that bypasses the controller and puts an extra battery in the circuit. However, this will offer no speed control on the speed boost, and it could be somewhat dangerous if you accidentally hit the switch before you are up to the existing top speed. You would need an additional charger to charge the extra battery.
Another option could be to just input higher voltage into the controller. There will be a risk of frying the controller. I would do a 6v increase and see how it holds up.
Finally, another option could be to use a higher-voltage controller. A controller might be somewhat expensive to match the amperage of the stock controller.
[url=/forum-topic/motorcycles-and-large-scooters/587-my-kz750-electric-motorcycle-project]KZ750 Motorcycle Conversion[/url]
[url=/forum-topic/motorcycles-and-large-scooters/588-fixing-my-chinese-scooter]900 watt scooter[/url]
Pic from http://www.electri
The old eGO's had a dual voltage controller 24 or 36 volt. The new ones are 24 volt only. The sevcon 24/36V controllers are still available. The motor will hold together at 36 volts but you will need aggresive additional cooling for it. I have a PDF of an ingenious design by an eGo owner (from a few years ago) using the old 24/36 controller. He basically added two 17ah 12 volt batteries for a 24volt range extender. Then the clever part - he fabricated a connector out of anderson power pole connectors which when plugged in one way was 24volt range extender (24volt and 61ah) and when flipped over it reconfigured the batteries such that it was 36volt and 34AH. Really simple and really effective. basically if you rode at 36volts range would be unaffected as long as you slow down to 24volt speeds.
Probably looking at dropping about $500 to do it right with the sevcon controller and a matching battery. They go over 30mph at 36V so it makes it illegal in the moped class for most states. I ran one at 36volts for a while doing some testing. It didn't feel safe over 30mph IMO. It was hard on the motor too spinning at up to 4500 rpm. I settled for added active cooling. Increased battery capacity (at 24volts) and regearing the bike to top out at 27mph. It's great there feels safe and stable and faster than 25mph keeps cars from breathing down my neck.