Direct Drive Hub Motors


Direct Drive hub motors are built such that the motor IS the wheel. There are no moving parts or gears to wear out making them mechanically robust and fairly silent in operation. Because the motor is always engaged, they can be used for regenerative braking in addition to forwards torque. But on the flip side, there is also a small amount of cogging torque present just to turn the wheel, similar in sensation to riding with a knobby mountain bike tire. They are also larger in diameter and heavier than geared motors of the same power.

The motors we sell are 3-phase brushless DC devices and are pre-laced into a bicycle rim. Crystalyte makes the Crown and H series of hub motor (and previously the 400/5300 series). Crystalyte is not the cheapest source of Chinese hubs, but few others come close to offering the variety and level of customization as Crystalyte, and for that reason they have been very popular with the project oriented DIY crowd. 
The H Crystalyte hubs are the latest generation of direct drive brushless motors coming out of China. This style of motor has a large (205mm) rotor diameter and a narrower stator width than the Crystalyte 400 series, with nearly 3 times the number of magnetic poles. This method of construction is quite material efficient, resulting in a hub that has a higher torque output and a better peak efficiency than the earlier direct drive motors (like the Crystalyte 400 series or Wilderness Energy) from several years ago.

Crystalyte H series

This is the motor series that Crystalyte came out with in 2011 to replace their 400 and 5300 series of hubs. This is motor is very similar in internal contruction the the Nine Continent 28XX motors, with 23 magnet pairs and a 205mm ring diameter. However, it offers a number of improvements over the 9C design.  Namely:
  • 35mm wide rather than 27mm wide stator and magnets, for ~30% more power
  • Full 18mm of space from the disk boss to the side cover, allowing for compatibility with majority of disk calipers
  • Cable routing through the sides of the axle rather than the ends, better protects the cables from damage and easier to swap nuts, washers, and torque arms on the wire side. 
  • Laced with heavy 12g spokes and a wider double walled alloy rim (a multi-gauge spoke wrench is included with Crystalyte motors for adjusting spoke tension)
While Crystalyte used to have a wide array of winding types with their 400 and 5300 motors, they have narrowed it down to just three in this series. We elected to only stock the H motor options, since the lower speed winds are a little too slow to be of much use with standard 36V or 48V battery packs.