Power Hub and Controller

Power Hub

I had many concerns when thinking about replacing the rear hub and gearing that was set up by Christiania.  I will admit, they did a great job in selecting the 7-speed Shimano hub.  The shifting was easy and smooth, the rear coaster brake was simple yet very handy.  When adding power to our bike, the rear hub replacement was the most convenient and cost effective solution, yet replacing the Shimano hub would mean we will lose two great features that were designed into the bike.

I had researched numerous power hubs for front or rear and thought about making a front wheel drive system of my own design.  What I finally selected was a 2000 watt, 36-55 volt, brushless/gearless motor made by Crystalyte, due to its ease of installation and proven technology.

Because this motor is brushless and gearless the reliability and lifespan should pay off, however a geared version of this motor is available.  Other advantages of the gearless motor is the speed it can produce and quiet operation but the disadvantage is the weight and  lower torque than the geared version.

As for sprokets, I am replacing the stock 19 tooth gear with a 15 tooth freewheel sprocket and hoping that one speed will be sufficient for riding around town.  If I find that a single speed system does not give me enough range, I can always add multiple speed cluster and deraileur system.

At the time of this post, the hub and rim are being assembled to make the 24" wheel that I need. We are excited to see the arrival shortly.

Motor Controller

The motor controller we selected has a range of 36 - 64 volts and can handle up to 3000 watts of power.  This controller from Crystalyte boasts reliability and smooth power delivery while also selling at a fairly reasonable price.  The controller will be tuned by the manufacturer to work properly with the power hub.

I opted for a thumb throttle due to the handle bar configuration on the WattCycle, however a half turn twist grip is also available.