# Transformation into an e-bike



## caverex (May 19, 2019)

I've got Fuji Gran Fondo 2.1 bike and I want to convert into the e-bike. Is it a good idea?))
Due to its carbon folks, the front kit wheel won't work out well as far as I heard so who can advise the best option for installing the rear one.
I'd appreciate if your proposition would be up to 500 bucks.
THNX


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## AC/BC (Jun 22, 2006)

The biggest worry is that the frame is carbon so you'd want a low-watt kit (maybe 750w-1000w max). The people on Endless Sphere seem to all think carbon is a terrible frame material for a hub motor conversion as it puts different loads of stress on the frame and people have cracked and snapped frames in the past... although these were high watt conversions... you'd probably be safe with a 750watt kit.

Also, you always want a rear wheel kit. FWD is silly and can be dangerous without a strong fork. On a road bike you'd want to convert to a steel fork.

If i was doing a road bike i'd get a MAC hub motor kit... but you'd want to look into if it's appropriate for a carbon bike.


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## richj8990 (Apr 4, 2017)

AC/BC said:


> The biggest worry is that the frame is carbon so you'd want a low-watt kit (maybe 750w-1000w max). The people on Endless Sphere seem to all think carbon is a terrible frame material for a hub motor conversion as it puts different loads of stress on the frame and people have cracked and snapped frames in the past... although these were high watt conversions... you'd probably be safe with a 750watt kit.
> 
> Also, you always want a rear wheel kit. FWD is silly and can be dangerous without a strong fork. On a road bike you'd want to convert to a steel fork.
> 
> If i was doing a road bike i'd get a MAC hub motor kit... but you'd want to look into if it's appropriate for a carbon bike.


May I ask why front-wheel drive is silly? There are certain advantages to all three types of drives. And that's why torque arms were invented, to prevent the fork dropouts from snapping. They work VERY well. By the way I converted FROM steel TO aluminum on the fork and everything is fine. Two torque arms, zero problems, way over 1000 miles so far and zero crashes. Don't believe everything you read on the net, believe what people have honestly experienced. If a guy puts on a 2000W front hub without torque arms, that's called the Darwin Award. That does not mean all front hub drives are dangerous. Understand the difference please...


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## Bigwheel (Jan 12, 2004)

"FWD is silly and can be dangerous without a strong fork. On a road bike you'd want to convert to a steel fork."

For sure it can and has been done wrong with disastrous consequences but I chalk those up to Darwin nominees. If looked at from a technical standpoint it can actually work quite well.

I've got 3k on this bike primarily on gravel and pavé roads with some trail work tossed in when the mood and opportunity strikes.









1000w peak, legal in OR where I reside, but used mainly in 500w mode, as set by my CA/controller interface selectable in 250w increments, for battery preservation purposes and the fact that it also provides enough speed over terrain for my purposes.

Bikes Direct brand carbon fork with carbon dropouts with a torque arm on the disc side. Bike also utilizes regen. I keep an eye on the fork for stress related issues but so far so good. I keep the axle nuts properly torqued.

After going through all the options over the years I find that front hub/throttle/cruise control is my preferred setup for road use. Allows for complete autonomy at the pedals that provides the best feel of the gearing in relation to terrain while the motor helps provides constant momentum nicely making up for my dead spot spin. Hill climbing on gravel is really good with both wheels driving. YMMV of course but I always get a bit tetchy when I see statements like above from people that have only based their experience on what they have read, not what they have ridden.


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