theWretched

Hey everyone,

I'm leading a student team competing in a university-sponsored sustainable technology challenge. Our team is building a custom electric assist kit for the Madsen bucket bike (check them out here).

We're hoping to use a rear, direct drive hub motor (this bike uses a 20" rear wheel, which is ideal for our purpose - the smaller size should gear the motor down to have more torque for those steep uphills with a load. Top speed doesn't matter too much).

My problem is that I don't know direct drive hub motors very well, and I'd appreciate your help answering the following questions.

Who are the manufacturers of high-quality direct drive hub motors? I know of Golden motors, Crystalyte, Amped... who else should I know about?

BionX managed to make a direct drive hub motor that's simultaneously powerful, lightweight, and doesn't give much rolling resistance. Has anyone else managed to pull this off?

Thank you for the help!
Henry

chvid

Nine Continent from ebikes.ca. They also sell Crystalyte and EZEE (geared) hub motors. The 9C and Crystalyte are Direct Drive.

spirit733t

a decent kit with excellent customer support is the papamotor kit..

their prices are very good especially for students looking for a great all in one kit..

the battery they supply a ping has an excellent reputation, I have heard people say the motor stator and copper windings are higher quality than the 9C.

the 9C is well known for having issues with installing a rear disc mount..

crystalyte is very well known and has lots of users and lots of documentation... and can handle high volts

for geared motors.. ( these are more effient at lower speeds and also provide a smoother ride if your not using the power on the motor.. the most documented is probably the BMC.. ( the V2 kit has a good rep but is being phased out, so hurry)

a problem with geared motors is that you have to replace the internal gears every 5000 - 10,000 miles depending on how you use it, they have more parts so more higher chance of going wrong..

DD motors are more reliable and have higher top speed generally, but lower hill climbing ability, also there is a magnetic resistance when the motor is not in use, so pedaling these with no power there is a slight drag..

I think in your postion as a student the papamotor is a great kit..

peSem

I would surely go with this BionX kit: SL 350 HT RR XL. It is one of the best kits available on the market today, and they are fairly easy to install.

chvid

Two thumbs up on 9C from ebikes.ca or ebikekit.com The older Crystalyte 400 series is a nice mid-powered motor if you can find one and dead QUIET. Generally, low noise is an under-rated feature of hub motors and quiet is a good thing. Conhis motors are very torquey - the black ones with the silver rings on the side-cover, and have more of a low whistling sound. The older Crystalyte 5304 and 5303 models are also dead quiet and superpowerful if you can find one, but very heavy. Aotema sensorless motors are approximately equivalent to the old 400 series Crystalytes. And there are the newer model Crystalytes available from ebikes.ca. I haven't ridden one of those. The crystalytes and 9C come in various winds which tradeoff speed for torque. I've got a Crystalyte 404, 405 and 406 on different wheel sizes, and two different winds of the 9C. The Conhis are a bit crudely finished comparatively but are cheap and powerful. I'm running a rear 9C on my recumbent trike and it is just right, spiking at around 1400 watts, and quiet enough to listen to the awesome wide voltage range stereo amplifier from ebikes.ca, which I can testify is loud enough for a parade and was used for one...No need to go any faster really.

Loud motors = bad music quality, stealth is good excepting the music. It very possible to build a kit bike and get a way "better"
bike for many purposes than a Bionx for considerably less money. A kit gives you 100% intentionality on power control and a vast range of motor options, a good reason not to buy a Bionx. The Bionx is presented as the Mac of ebikes, highly proprietary, evolved, and locked in. A purist experience. Maybe. By the way I have a dead Bionx in my basement. I'm going to gut it and run it sensorless with an external controller some day. A normal throttle will suffice. The batteries cost too much etc.