Drive Train - In-Wheel Electric Motors

I looked at a bunch of hub motors; they're in-wheel motors that run on the wheel's axle and connect to the rim via conventional spokes. After looking at all of them, I'm convinced that the best hp/lb ratio by far is in the motor from Tidalforce.

The motor comes in 500W, 750W and 1KW versions ... naturally, we're spec'ing 1KW (see thoughts on speed below) - priced at ~ $1665 ea. - this will be a big ticket item for the bikes.

Update ... just found the 1000W motor for $1125 here.

The number of motors spec'd must be given some thought - as must power consumption - the rider must be able to switch motors on/off individually. It doesn't look like the controller that comes with the kit can natively control 2 or 3 motors - must look into this. Tidalforce talks about the dashboard and the throttle that control these awesome motors.





Tidalforce also offer an in-hub rechargable battery, usually with this motor in a kit. I looked at it & decided on the auxillary rechargable batteries instead (more later). I want to use the hubs for motors, not batteries - yes, speed IS the point (within the speed limit of course). The point about speed is that if this is a 3-week continuous journey, we'll have sore asses & probably won't cut out the time. Where-as, if we can get average speed over the distance to 40mph, it would take just less than a week!!! So, speed's where its at - just because its electric, it don't have to be impractical.

Back to the motors then ... (spec's below)

We'll put in at least two; one each front & back - but I'm going to also look into the possiblility of two rear motors. They will run in a fat lowrider spoked car wheel, there's more than enough space for two motors, so if there's a way to make the bike run better with two rear motors, then let's do it!

The front motor also makes sense (just one of them)! We should get some downward thrust & good front-wheel traction from the aerodynamics on the solar panels on the forks.

Some useful notes on this motor from Electric Rider ...

Installation

The hub motor has an inverted design. The axle and torque bar must be properly restrained while the hub shell rotates. The 750W motor is cable of 50 foot pounds of torque. The torque bar bolt, located 4” from the axis, must be able to consistently withstand loads in excess of 150 pounds. Failure to restrain the torque bar will allow the stator to spin, pulling on the external wires with tremendous force. Great care should be taken to make sure the torque bar is properly secured before operating the motor.

Cabling

The “Program” cable can only be used by WaveCrest technicians to program the motor. The “Data” cable must be connected to the motor data cable on the Alpha 750 Dashboard Assembly. The “Power (+)” and “Power (-)” cables are to be connected to any 36VDC supply capable of up to 40A peak and 30A continuous current draw.

Speed

The 500W and 750W versions have a maximum speed of 260RPM. The 1000W version has no set speed limit. The maximum speed of the motor in your desired application is based on the load.

Stuff that's included in the motor kit ...

Each Kit Includes:

Tidalforce rear wheel motor assembly include

1. Freehub adaptor

2. Freehub axle

3. 7 speed cassette

4. Quick release skewer

5. Torque bar bracket

6. All wiring for the bike is included and has been set up for you to just plug in and go. Wiring can be custom adjusted by FAE if you have an extremely long or short bike.

Control System includes

1. Dashboard with key switch

2. Two Tektro brake levers

3. Thumb throttle

4. Motor data cable

5. Battery data cable

6. Power harness

7. Neoprene cable wraps.

10. Charging time is 3-6 hours. Range of up to 20 miles on a charge

Specifications from the Tidalforce website ...

Here are some of the Tidalforce Bikes ... awesome ...

Specs & Pics of the io (~$2800)

PERFORMANCE
● Maximum speed: 20 mph (32 km/h)
● Range : 20 miles (32 km)
● Weight (with front hub battery): 64 lbs (30 kg)
● Gross payload: 350 lbs (160 kg)

BICYCLE
● Rider can add power with pedals or propel vehicle
on human power alone using 21-speed gears.
● Strong, light aluminium frame.
● Comfortable, adjustable gel-padded seat.
● Double Crown Suspension Front Fork, 26" wheels, linear pull brakes.

MOTOR
● 500-watt WaveCrest Adaptive Motor system provides exceptional power.
● Unique WaveCrest DSP controller delivers high torque across all speeds.

BATTERIES
● Front hub battery: 36V NiMH
● Charging time: 3-6 hours