Hub Direct drive motors

Grin Technologies has been slowly working away at making their own direct drive hub motor for electric bikes and is currently in a beta/pilot release program. The idea first took roots in 2010 when we were impressed with the performance of imported direct drive hub motors based around the 23 magnet pair 205mm diameter motors, but increasingly frustrated by their poor mechanical compatibility with modern bicycles. It seemed like there was always some kind of shimming and adapting needed on the axles to get disk rotors to align right, calipers to fit, dropouts filed, torque-arms retroactively installed etc.

We thought, wouldn't it be great to take this basic 205mm direct drive motor standard but make the mechanical side of things fit flawlessly with the standards of modern mountain bikes in North America? That meant first and foremost being compatible with thru-axle forks, but while studying the existing imported hub designs we realized there was lots of opportunity to remove material and shed significant weight without sacrificing motor performance. After retooling every aspect of the motor side covers, magnet ring, stator support, and axle, we were able to eliminate over 30% of the mass, bringing the 27mm wide direct drive motor from 6.2kg down to just under 4kg.


I  contacted GRIN technologies in Canada through email without doubt the best at DIY adapting technology’s for a realistic market place such as there through axle motor and there high power motors high amp but small controllers

I was considering using chystline motors high powered and reliable but heavy with no realistic idea of the EU market place there laws and regulations and what we need in saying that I will not rule them out in future talks


But Justin’s communication has been great solid advice where I need it and giving me food for thought in the application of his motors and controllers types of battery’s to use for small powerful packs for the DH bike that have a better C rating for high amps, he is a busy person well known and a world of experience he is willing to share and with the Mungrul project support can come in two ways cost savings or solid advice and support to save us on time and cost in the long ru

GRin hub arrived

The hub motor from GRin arrived, it was  packaged well and I got it laced up in a 20inch rim, it looks frigin great, the phase runner controller is small neat and heavy but you can feel the quality


Justin gave me $200 of the standard winding hub motor because of a scratch or something but I can’t see it


The motor looks great and seeing it in real life and comparing it to my other motor it’s twice the size and the power I will get from it I think will be great

But having it as a threw hub allows me to build the free rider attachment using the triple crown shocks without making any other parts to mount the fixed axle motor I can mount the brakes on the shocks as well not having to make anything more. once I have built version 1 of the free rider I can use the motor from GRin on the DH bike as well making it interchangeable between both EVs

The ultimate goal will be to make both EVs parts interchangeable shocks, motors batteries and brakes through versions and trial and error

I hope to order more of these motors in the future as dealing with GRin was great, there passionate about there work and seem to be excited about mine pleased to giving there knowledge with pride in there technology being used in mine.