Front hub motor for fatbikes (15x150 through axle)

SurlyNate

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Does anyone know of a drop-in solution for a front hub motor for a 15x150mm through axle? Looking for something for my Big Fat Dummy to aid in hauling tools for trail work, but want something simpler than mid-drive setup with all the associated complexity. Just need a bit of assistance.

Thanks!
 

high_desert_mud

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Doesn't exist, not for your application :(

I *JUST* set myself up for the exact same bike (BFD is the best bike i've ever owned - likely the best bike ever created :) )

What i did is replace my fork with a steel 135mm (eg Classic Mtn Rear) fork, and build a rear non-offset-side wheel on a rear motor. I swap the motor on/off, so i pressed on a crown race, and replace the whole front fork.

What i
My build:
Grin GMAC build (proper torque arm, _geared_ regen braking can bring whole bike to a stop by itself, power capable to be durable long term on a loaded bike PhaseRunner controller 52v 14ah 52v pack (the 21700 model was on sale) soma battleaxe 135 fork. Might replace with a surly fork when the non-side-offset versions get back in stock. (the three options i found that could be had new: surly pugs or moonlander NONoffset (not in stock), soma battleaxe (some old stock to be found), and a steel fork off of a tumbleweed bike (can be bought new, in-stock).

Some details:
Cargo is a challenging application, for both torque & weight load, as well as power. This limits your realistic options. Grin strongly advised against an small motor such as g301, for instance, even though I am only wanted a "1x human" (~250w MAX) build) regen braking is a huge plus, to save/augment the brakes (only ~10% range recoupe MAX, likely ~5%)

hope that helps! Look at my thread history for more details, i asked some of the same questions here.
 
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high_desert_mud

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Forgot to mention: the best option I found for thru axle was the grin "all axle" motor - I passed and went 135 because:
- as Grin (ebikes.ca) points out, to support the wider axles in that particular design, they have to use weaker bearings (*AND* the wheel must be de-laced to service :()
- it can not regen. Compared to the GMAC which takes a ton of load off my brakes.
 
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