Ebike thoughts… conserving battery power

The Power In Motion 500 watt ebike hub motor installed last week, disengages the motor when it is not driving the bike. Letting go of the throttle provides some audible indication the hub has disengaged. This conserves battery power since you can continue pedalling just like a normal bike, hitting the throttle to climb over hills or just to get up to speed then not using the motor again until you need to.

Therefore, calculating the range of an ebike is essentially determined by how much pedalling you do and how often you need to use the motor. Its a good idea to take a ride and use the motor almost exclusively to determine the minimum distance between charges.

Some hub motors do not disengage the motor. When the motor is not producing power you then have to pedal against the resistance of the motor with some makes of hub motors. So getting one that disengages the motor is really important if you want to use the bicycle mostly under pedal power.

Battery capacity was always a concern for me. As batteries are recharged, they gradually lose the ability to hold a charge much like a cell phone or any other rechargeable battery device. Batteries have a limited life. It is important to keep this in mind when buying a battery. The higher the battery capacity, the more gas is in the tank before you have to refuel (recharge). So when the battery begins to age and can’t hold as much charge, you’ll be happier to have extra battery capacity since you’ll be able to use it longer before it can no longer hold enough charge for your regular trips. It is important to note that batteries for ebike kits can easily cost more than the motor and installation. A $500 motor could easily require a $800-1500 battery depending on the range you need.

Although the ebike motor was purchased primarily to pull larger bicycle snowplows and to plow faster with the same pedalling effort, it also begs the question as to whether an ebike makes a good touring bicycle.

On a recent test ride I noticed that I was able to climb short steep hills with motor assist and without losing much speed. One steep hill in particular would require downshifting and standing on the pedals to climb the hill at under 15 kph. With the motor assisting, I could climb that hill in top gear at around 25kph. Quite a difference!

Generally when bicycle touring, people prefer to choose routes that aren’t very hilly because of the heavy gear that needs to be carried for bicycle camping. Often they’ll have a few hills where motor assist would really help. Then they can go back to pedalling along more level ground and this increases the range before the battery needs a recharge.

Using the motor sparingly and only when needed, ebikes can travel a surprisingly large number of miles in a day, especially if you can stop and recharge the battery for 5 hours or so in the middle of the day. On long summer days, it is very possible to double the number of miles provided by the battery. So a 50 km battery range could make it easy to cover 100 kms without pedalling. Pedalling could easily boost that range to 100 miles. Having a good charge left at the end of a long ride can make the hardest part of the trip more enjoyable!

A 90 km ride from Calgary to Chestermere would be a good way to test the range. A 40lb bike with a 20lb ebike kit is essentially a 60 lb bike. The rear rack weight limit is probably around 20lbs minus 9lbs for the battery. This leaves about 10 lbs for gear which is quite acceptable for day long rides.

Bicycle Snow Plowing is a new winter sport!


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