I have modified my bike to take a home-made battery pack, doubling the range per charge.

If you open the original battery pack, you can see how the batteries are wired together. By adding bananna jacks on the bottom of the pack, soldered to the original leads inside, I can simply plug in an extra pack. That easy.

I then used a simple plastic mailbox mounting base from the local hardware store to build an add-on battery pack. The mailbox base was the perfect size for the project and it had all the holes pre drilled into it. For extra support I used some steel bars on each side, again using the existing holes in both the bar and the plastic frame.

To mount the pack onto the bike rack I used simple metal \"J\" hooks and \"wing\" nuts. It fits perfectly. See pic below.

With this setup I was able to ride up into the mountains on a four hour ride while pedaling the whole time. I only used the motor to assist in climbing up hills. Down hill I simply pedaled in order to save battery power. The total round trip was about 24 miles. When I got home, the batteries were just giving out.

I must admit though, this is one very heavy bike to pedal uphill. The motor can not pull itself alone and you would not want to use up the battery that fast anyway. The power light goes immediately into the red on these high hills. It was quite a workout for both myself and the bike. Dont ever let anyone tell you that riding an electric bike is a lazy sport. If you want to increase range, you must use the pedals.

On normal, flat roads, I estimate I get about five miles using the motor alone and the original battery pack. With pedaling, I can double that, but not much more. I have found out that by only using half throttle, you can greatly increase mileage.