An electric motor mounted on the Mountain Bike will surely turn up their noses at many purists, but it is not a process for doing less work, but merely an exercise of electromechanical applied to our favorite vehicle.
We say that is a good alternative to the scooter going so fashionable nowadays.
The electric bike can and must become the real alternative to combustion engines on two wheels.
Light, agile and with good speed and good battery life, the response of the rider to the pollution problems of the third millennium.
At a cost not unbearable and many hours of work we can do to us, what car and motorcycle manufacturers promise for years and have not yet put into practice.
Sell gasoline (a expensive price), it is convenient to so many .... but not to us.
Electric Bike - 700W brushless motor 36V
This is an experimental installation of a brushless motor on a normal bicycle MTB, turning it into an Electric-Bike.
The engine's power gets used to 700W and above, so it is not a production code that must be limited to 250W. The tests shall be made only on roads not intended for off-road traffic circulation.
Kit with Chinese, it is not necessary to make changes to the bike, just replace the rear wheel with the engine fitted. It 'necessary to mount a good tire, robust and check the centering and tensioning the spokes.
Should also be mounted throttle and brake levers with sensors braking.
To give a better glide were mounted two tires inflated road to 3ATM.
- Frame Decatlon ROCKRIDER 5.3 size L
- Mounted engine 6 * 10 of Nine Continents.
- Control 500/800W of Nine Continents.
- Maintained rear disc brake.
- Front disc from 206mm
- Shimano 7 speed
- Battery LiFePo4 48V 10A battery charger and the V-Power
- Total weight 25.8 Kg - Kerb bike weighs: 10.1 kg 15.7 kg front and rear.
- Max speed 38kmh-Autonomy in plain 40-50Km
Good performance for medium pace, good balance in corners and on rough terrain.
Electric Bike principle of operation.
This is the configuration of the principle of operation, a microcontroller is charged to generate the PWM signal for the three phase bridge to Mosfet command.
From the engine comes the control signal detected rotation with Hall effect sensors.
The accelerator control (speed command) modifies the value of voltage applied to the ADC that is, by varying the% of the PWM control, by applying more or less power to the load represented by the windings of the motor.
- The reaction is all on the engine mounting bolts which in this case are larger in size, this close to the hub with the greatest possible force in order to avoid rotations of the pin hub.
- The motor cables coming out from the left side of the hub holes. Are fastened to the bicycle frame and well protected, because in the event of a fall side is easy blanking.
- And 'advisable to fit additional protection in metal to protect the cables as it is very important to their integrity.
- On the right side of the engine assembly is mounted pinions. In this case only 6 gears.
- Really useless mount the engine of change 9-speed, with the integration of the engine would no longer be used.
- Going to the motor gear is used very little, always just added the report along 46/14, sometimes as short as 1 or 2 if you want to keep the lower engine power.
- From the pull-ray and treat well the important balancing of the wheel to travel well to 30kmh.
- From heal well centering rear brake.
- The wheel assembly engine weighs about 8kg.
- Battery 36V 12Ah LiFePO4 complete BMS
- End of charge voltage = 45.0 V
- Power detachment BMS = 33.0V
- The system is fixed on a normal roof rack aluminum.
- In series to the battery, important to put a safety fuse 30A.
- Batteries and inverter weighs about 5 kg
- The idea was to also mount the batteries inside the triangulation, in the bottle, but the batteries do not have the suitable size for the arrangement, therefore, have remained on the luggage rack.
- The BMS and the Charge, has unfortunately been used a male plug for 220V and some may mistakenly connect to the network, be careful and only connect the charger dedicated. It 'still a good outlet for charging that holds 6A.
-Power Meter, mounted on the handlebar.
- Allows the measurement of the power consumption and very important parameter, the Wh consumed, value to be monitored to determine the remaining.
- This model is easy to remove the resistor Current-sensing and bring it directly next to the battery, to avoid stretch the power cables, and then get to the instrument with cables smaller and lighter.
- To find the best arrangement, for easy operation and that does not interfere on the command rear derailleur.
Road test.- In order to start the bike weighs: 7.0 kg front and 22kg rear.
- The battery is good to bring in more central and lower, to better distribute the weight.
- Let's say that with batteries (36V 7Ah), it is possible to reach the maximum performance, the performance is still remarkable.
- The motor starts already pushing hard to stop riding, helping with the pedals in the strong acceleration.
- With a charged battery, plain reaches 30.0 km / h, helping with the pedals on the highest gear available on the bike that is 46/14 you can easily reach the pedals with 34kmh then you go out of sight and you can not give further increase.
- The efficiency of the electric motor can be seen heavily uphill climbs where you usually pedal go up with the 26/20 or more, you deal well with the 46/16 pushing not too much, you go quietly 20kmh. Clear that the batteries sit almost immediately and should desist.
- It 'better to have a frame twin suspension, as the extra weight is felt a lot over bumps and jumps.
- Basilar use the power meter, which in addition to the instantaneous values of current and voltage battery, it gives us the power used and the instantaneous value of Wh consumed from power.
- As noted is the power necessary to go on a plain 20kmh is around 100-150W, for uphill light are consumed by 300-450W, while for a demanding climb the salt consumption up to 850W limit value given by the battery pack 12A
- Pushing hard on the pedals to recover up to 200W in the plains, rising less, depending on the preparation ....
$ A little prices $Engine: 100 euro.
Battery: 400 to 500 euro.
Unit: 85 €.
Power Meter: 25 euro.
Throttle: 23 euro.