Hiya from Aberdeen

Hello everybody ,I am a Spanish guy living in Aberdeen ,and after have been reading the forum for a while ,I want to start my project.

The bike is going to be a Dahon Speed 3 ,folding 20" wheels ,with 3 speed hub.After reading the forum ,I am thinking in a Cute Q85 front wheel engine ,250w ,because of the fork size in the Dahon is only 83mm.

I found the engine in 3 different versions ,201rpm ,261rpm and 328rpm.As I am 90kg rider ,and there are many up hills in Aberdeen ,I choose the second one ,261rpm ,trying to find balance.

I am going for a 36v, 10Ah Li Ion bottle battery with integrated controller ,and here is the first of my doubts, which controller do I need? ,there are two options ,a sensorless square wave ,or a Hall sensor sine wave?, the idea is ride the bike with a thumb throttle as much time as I can ,I would like to use it for commuting ,and I don't want to reach the places sweating ,I already have a proper MTB to keep me fit ;-)

There is another option with the controller, 90v-132v, or 200v-264v, I guess that my choice must be the second one.

I am not looking for a big speed ,as I want to keep a low profile ,just go with the same speed than a regular bike ,but without pedalling, and I prefer have a bigger torque.It would be enough for me doing about 15-18 miles with one battery charge.

Any advice would be most welcome ,thanks in advance

Mark

PS Excuse my English ,I am doing my best ;-)

The 260 rpm motor will give good power up to about 20 km/h, then reducing to its maximum speed of about 25 km/h.

The normal Q85 has hall sensors, so get a sensored controller. It might be a good idea to check with the supplier that the motor they offer is sensored, because there are sensorless versions too. You should also check that whatever controller you choose is compatible because the Q-series motors don't work very well with some.