For a long time, the quality of electric conversion kits available here in NZ has been variable to say the least. Thankfully NZ company Lekkie have designed an electric conversion kit that matches the quality of our SmartMotion electric bikes.
Here's one we installed on a customer's bike recently - a fast road commuter with a lot of practical touches.
Lekkie have designed two kits. The one installed here is the Summit, which replaces your bike's crankset and drives through the chain. This means the motor's power can make full use of your bike's gearing - super-low gears for steep grades, and high gears for a greater top speed. We'd recommend this for maximum performance, or if you've got an unconventional setup (like a smalled-wheeled bike, cargo bike, hub gears etc).
Lekkie's other kit is the Explorer, which replaces the rear wheel entirely. It's a simpler design that requires less modification to your bicycle, and is perfect for commuters and cruisers.
Both kits are supplied with the battery and motor, but also a pair of replacement brake levers featuring safety cut-outs (so you can't brake and power the motor at the same time) and an LCD display showing things like speed, range, and total distance. Both kits also have a pedal sensor (so the motor is activated when you pedal) and a conventional throttle.
The price of the kits is $1,690, plus $180 fitting. We're not allowed to sell the kit separately - this is a good thing, though; it means we can talk through your options and make sure your bike is in good working order before we start.
For more info on Lekkie, check them out here, or visit their website.