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Dual wheel drive e-bikes by Kinetic. Here’s why.

Kinetic is famous for dual wheel drive bikes, where the front wheel is powered electrically and the rear wheel has internal gearing. this is the system that NZ Post settled on, that several cargo e-bike companies use and the reason  is twofold.

1. Front wheel electric assist bikes allow the rear wheel to have internal gearing. The advantage of this cannot be overstated. Gears can be shifted from a standstill, th chain cannot fall off, and there is next to no maintenance. in addition,  the chain drive can be completely covered by a guard.

2. Front wheel drive employs corrective steering  to your ride. It is truly power steering, and you have to demo ride the bikes to appreciate how this assists you over bumps and in tight maneuvers. It is safer because it avoids skids and loss of control.

By contrast, rear wheel drive bikes have to use derailleurs that require much maintenance, cannot be shifted from a standstill, and the chain cannot be enclosed or kept from falling off. The rear wheel actually pushes the front wheel into a skid, making them a poor commuter choice. Taking off up a hill with an ebike in the wrong gear, and struggling with it mightily, is a common problem with rear wheel drive bikes.

Six  Reasons to use an Electric Bike Hub  Kinetic e-bike. (formerly eZee)

1. Great Performance. While staying within the legal limit for NZ roads,  Kinetic has packed more permanent magnets into the hub and increased torque is the result. Expect to flatten hills and slice through headwinds better than other brands.

2. Quality Name brand components.   We distribute a quality product has unlimited life built into the components. German wheels, internal Shimano gearing, German lights and Sony lithium cells. Quality gear costs a bit more but it is better value. Our batteries are tested under the EU requirement for safety.

3. Technology leader.  Kinetic has been advancing the state of the art in electric bikes since its inception and the team of international  experts continues to make advances that lead the way to customer satisfaction. Six NZ Councils have picked our ebikes for the advanced technology in them.

4. A real brick and mortar company. Both Electric Bike Hub and  Kinetic are the real-deal  service oriented established e-bike vendor. We have twenty stocking ebike shops and five tech centres,  waiting to give you a quality introduction to the operation of our bikes, put you on for a test ride, and serve you after the sale. We have been doing this for 11 years in NZ.

Our products and experience set us apart from the typical generic Chinese e-bike junk pedaled by Trade-Me entities and other over-priced imports. We earn our customers the old fashioned way.

5. Passion for the products. Our president has ridden our electric bikes across Africa, China, Australia, and the UK.  No one tests e-bikes the way we test ours. The years and distances have given us experience and product refinements that you can count on.

6. Reliablity. When you are out on a long rail trail ride, you need to be able to count on all the components that makes an e-bike work. Ours do and you can!

More on Performance

From a biological and mechanical viewpoint, using a bicycle is extraordinarily efficient. It’s simply the most efficient human-powered means of transportation in terms of energy a person must expend to travel a given distance. From a mechanical viewpoint, 85-90% of the energy delivered by the rider into the pedals is transmitted to the wheels through the gears. Our electric motors are similarly about 82% efficient. it adds up to remarkable zero-emission transport.

A person biking at low to medium speeds of around 10–15 mph (16–24 km/h) uses only the energy required to walk. Air drag, which is proportional to the square of speed, requires dramatically higher power outputs as speeds increase. If the rider is sitting upright, the rider’s body creates about 75% of the total drag of the bicycle/rider combination.

There are many erroneous claims in other electrical bike brand brochures that grossly overstate their range. in the real world, you will travel at higher speeds and over hills and into headwinds. These adjust your actual distance downward, but the performance is still great.

The range of the battery depends on:
a) The power delivered by the motor,  if it’s a very weak motor running with low amps, the battery pack could run for a longer distance, but would be helping you very little. Higher power motors have more hill climbing grunt, and higher assist speeds,  but can use more battery assist doing so.

b) Speed creates air drag , which increases at the  cube to speed, getting much more pronounced as you go quite fast.

c) energy capacity of the battery pack. Larger capacity batteries have the reserve to carry you further. Also the quality of the cells determines the overall performance of the battery.

d) overall efficiency of the electric system and mechanical system of the bike. E-bikes are inherently very efficient, but the motors must be matched to the components and all must be able to operate without creating excess heat. This requires quality components and design.

Battery Safety

One of the things cheap ebikes have in common is untested battery systems. They have not been certified  safe in the UN38.3 battery testing requirement set up by the EU.  eZee Kinetic has our batteries and BMS systems go through this expensive and demanding testing to certify to you and to these critical importing countries, that our batteries are safe and built with the right stuff. Do you want to bring into your home anything less? You will pay more for this quality, but quality is long remembered after the price is forgotten.

The traits of an exceptional electric motor.

1. Energy efficiency
2. Performance: Power to weight/dimension ratio
3. Reliability
4. Aesthetics

Weighing at 3.78kgs, the eZee Kinetic  brushless PMDC motor with inbuilt planetary reduction gears and freewheel is built in-house with exceptional technical specifications. With minimal drag, a freewheel spins freely like a normal hub when the motor is not on. Contrarily, a Direct Drive motor with similar output is heavier and has a high drag when not powered.This is the reason that NZ Post and dozens of other companies use the planetary geared brushless hub motor.

1. Motor efficiency loss can be attributed to:

a) Resistance in the copper wires used in the motor.
Using high grade copper, we achieve minimal winding resistance in our motors.

b) Iron loss as a result of Eddy currents.
We reduced this to the min. by using high grade silicone steel plates (for thinness)for the stator.

c) Parasitic lost from bearings and other mechanical moving parts.
We employ high quality bearings from Japan NMB and Germany FAG. Dow Corning silicone greases for the planetary gears.
eZee Gen 3 motor has an efficiency of 83 % with 250 rpm and 25 Nm of Torque. It is essential to qualify the torque output together with the speed.

2. Power / weight and dimension ratio. 

As a permanent magnet motor the obvious critical component is the magnet.
We use N35UH Neodymium magnets that retains magnetic properties up to 180°C, fitted in optimum size with min. air gap to the stator.
US / Canada nominal rated 500 watts motor delivers 30 Nm torque with 200 rpm speed at 22 amps or 800 watts.
It weighs 3.78 kgs and has a diameter 186 mm.  An ideal dimension and weight ratio for its power output. Our nominally rated 250 watts motors for EU market (EN15194), delivers that same high torque with a speed limit of 25 km/h or 200 rpm with 26” wheels.

3. Reliability

Using PWM ( Pulse Width Modulation ) technology, eZee Kinetic’s motor uses state-of-the-art Honeywell SS41 Hall sensors. The planetary star gears are machined from cast Nylon 6 rods for high strength and durability. The motor hub covers are die cast and CNC machined from high grade Al alloy ADC 5, providing good corrosion resistance. Anodized black option gives provides even further corrosion resistance.

4. Aesthetics

Hub motor covers are available in gloss finish and machined surface, or also available in anodized black or silver hubs.Simple, elegant, easy to clean and maintain.

Controller

Kinetic’s controller is engineered with the best and most reliable electronic components in the market, delivering ultimate performance and reliability. Operating at 36V and 48V, it has an overload protection at 20amps, using IRFB 4110 mosfets that take high amps and voltage. The circuit board is sprayed with conformal coating and then a layer of silicone potting compound is applied for further corrosion resistance. Die cast Alloy casings are potted to make them impervious to water.


 

 

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