Electric Bike project description

When I received the batteries I mounted them onto the frame and connected them up using 25mm welding cable. A string of six 12 volt bulbs was made to test the contactor action, then they were connected in place of the motor to check the controller and that the pot-box was wired up the right way. It worked fine, with the lamps turning brighter as the twist grip was turned. The last test was to connect the motor and see if it all worked, this was done out of gear and on the centre stand for safety.
When the ignition was turned on and the starter button pressed there was no sound and nothing blew up! As the throttle was increased there was a 1.5KHz tone as the motor started to turn, this is a characteristic of the Curtis controller and I was expecting it. The noise stops as soon as the motor gets up to speed. Once satisfied that it all worked I quickly took it out on to the road and was

amazed at how well it pulled away, with plenty of power to give good acceleration up to a top speed of about 40 mph.
Once I got all the legal paper work sorted I stated using it for commuting the 16 miles to work. Checking the battery voltage on arrival shows about a third charge left, this seems right and should give the calculated range of 25m miles.
I experimented with running it in top gear all the time, though it worked o.k. I reduced the current limit on the controller and use 3rd gear to pull away then 4th once moving, this reduces the current drain from the batteries.
So far I am very happy with its performance, more speed might be nice but I think that will be another, lighter, bike project.

Some more pictures:-

This is the box that contains the voltmeter input selector [click].

This box has the charge input, it just isolates the auxiliary battery when charging [click].

Bike showing the charging cable from the charger box [click]

Another view of the finished bike [click]