TECH NYSTROM SPECIAL
There are many ways to design and manufacture an ebike. Nystrom Bike does it with great care and high tech methods.
The electric motor is powerful and robust. It’s a 48V brushless motor with up to 1000W power. We have choosen to use such a powerful motor for several reasons.
Some markets allow a high power bike while most European countries are limited to 250W. In the latter case we only use a small part of the motor capacity and it will have a very long life.
The motor which is positioned in the rear wheel has a built in reduction gearbox and a freewheel giving almost no resistance when pedalling without electric assistance. The unit comprises rear hub, motor and gearbox.
The gearbox is a planetary unit with a reduction ratio of 5:1, meaning that the wheel spins one revolution when the motor spins five revolutions.
The Nystrom Special is equipped with a 2-speed gear, for both high- and low-speed pedalling.
The gear system is a special design integrated in the bottom bracket. It’s controlled by a handlebar mounted selector. This means you can ride fast or slow, with or without electrical assistance.
In the picture above you can see the rear hub axle installed in the frame. It’s designed to keep the rear wheel exactly centered in the correct position.
We use stainless steel torqueplates to carry the high motor torque. It’s mounted with strong stainless bolts.
The Nystrom Special is equipped with a thumb throttle. On some markets it’s allowed to use the throttle as the sole means of propelling the bike. In most European countries it’s only allowed to use electrical assistance while pedalling, although it is allowed to use the throttle to select the walk mode.
Despite the above throttle restriction, it is allowed to use the throttle to activate the walk mode, meaning that the throttle can be used to propel the bike very slowly, 6km/h, without pedalling. This is useful when walking with the bike beside you.
The Nystrom Special battery pack is designed for optimum performance and a high level of safety. We have chosen to use the Samsung INR18650-35E cells. They have the highest energy content of all. On top of that our pack uses many cells, 65 in all. Together they make up a fantastic pack containing 760Whrs, conservatively measured.
The Nystrom Special uses a custom designed battery management system to handle both charging and driving in a safe manner. The battery is continuosly monitored for many safety parameters, as well as balancing the cells during charging. All in all this assures a high level of safety.
The Nystrom Special is designed with dual safety, both during charging and riding.
Charging – The battery is monitored by both the charger and the BMS.
Ebiking – The battery is monitored by both the motor controller and the BMS.
The motor control is state of the art, utilising field oriented control. This is a way to control the magnetic fields inside the motor in a very precise manner. It ensures that the motor allways performs optimal as well as being very quiet and uses the battery energy very efficient.
The Nystrom Special automatically supplies electrical power when pedalling.
The battery tank is an integrated part of the bike. The shape follows the frame contour in a smooth way. In addition to the elegant design, the battery tank houses all the electric components, the battery, controller and wire harness.
The battery tank is manufactured using glass composite, a material which is both strong and temperature resistant.
We worked hard at designing the battery tank to be both functional and elegant.
The Nystrom Special uses a keyswitch to power up the bike. It has a very important safety feature. When switched off, not only does it cut power to the motor, but it ensures that no electric current can leave the battery pack, leaving both the motor and the controller electrically isolated. When turning on the keyswitch, the motor is ready to assist you when starting to pedal the bike.
When done biking – turn off the keyswitch to power down the bike.
If you forget to turn it off, this will be done automatically after 30 minutes of inactivity. The same goes for forgetting to switch off the headlight.
The headlight is a very robust unit with a power efficient H4 LED bulb. The headlight brass rim matches the elegant brass bell.