Has anyone tried building a hub motor wheel with your rim? Is it complicated?
- Thread starter Katrina92
- Start date
Stefan Mikes
Gravel e-biker
- Region
- Europe
- City
- Mazovia, PL
Any hub drive motor for thru-axle frame?
Keyde makes a thru axle compatible rear hub motor that has torque based assist (and reported to have an inclinometer to help on hills?). Appears to be a very clean install because the controller is enclosed in the motor housing and has a wireless control so the only exposed wire is to the battery. Other aftermarket hub motors tend to be a mess of wires, usually too long that have to be routed or coiled to take up slack, not to mention cadence rather than torque sensing. The other options would make a premium carbon road bike into a Frankenbike as you have note. There aren't many thru axle compatible aftermarket hub motors to choose from so it's unclear what the OP is referring to as she isn't clear about that.
Chargeride
Well-Known Member
I'd have to break a lot of spokes on a ride before I tried to replace them with those spare ones I never have.
Grin's aptly named All Axle Hub Motor. Choice of axle type (thru or quick release), dropout widths (135-170+), cassette type (HG or XD), different stator widths, and onboard torque sensor option. It's a DD motor so is a bit heavier than most of the smaller geared hub models ... but you get the option of regen.
It's probably a bit better suited for a heavier duty bike than a traditional lightweight road bike. Really ideal for cargo or more robust commuter setups.
Stefan Mikes
Gravel e-biker
- Region
- Europe
- City
- Mazovia, PL
I was thinking about the possible conversion of @Katrina92's racing bike.
A traditional racing bike.
A road racing e-bike.
I think converting a classy road bike to the electric would kill all the appeal and excellence of that bike. E-bikes are designed from the scratch with a reason.
@Katrina92: Have you had a look at Trek Domane+ e-bikes?
- She needs to find a hub motor compatible with a thru-axle and of the spacing equal to her existing rear wheel hub
- A new wheel has to be built, possibly with a higher number of spokes to match the motor demands and the increased weight of the rear wheel. It would be not an inexpensive option, and Katrina will lose an excellent wheel. New wheel: a new rim, new spokes, the motor, the labour.
- The speed magnet (and the wheel speed sensor) need to be installed somewhere: on a spoke or on the brake rotor?
- Motor wires have to be routed: how?
- The heavy battery has to be installed somewhere on a lightweight and delicate frame. Where and how?
- The controller has to be installed somewhere. Where?
- How can you install a typical 22.2mm handlebar remote and a display on a 25 mm diameter drop bar handlebar?
A traditional racing bike.
A road racing e-bike.
I think converting a classy road bike to the electric would kill all the appeal and excellence of that bike. E-bikes are designed from the scratch with a reason.
@Katrina92: Have you had a look at Trek Domane+ e-bikes?
Assuming the All Axle motor would be suitable for her ...
No external speed sensor, it's built into the motor
Wires usually go on the underside of the stay, and you try and color match the ties and wraps required. It's not going to be an invisible setup, you're really just trying to minimize the obvious changes.
Like most road bike conversions I would initially consider using a bottle style battery - these are usually available in the 300w range. Some bottle batteries also include space for a controller.
One alternative to the bottle style battery would be one of the smaller capacity Hailong battery cases with the integrated controller - typically in the 500w range. Visually this would however scream eBike. Mounting would be on the downtube and would likely require an offset mounting bracket such as the Grin triple Bob. This type of bracket would also add stability and strength to the battery and put less stress on the threaded attachment points.
Another battery alternative is a custom setup with a small frame bag, either below the top tube or a triangle bag. Visually quite stealthy but likely wouldn't be available with any certifications.
There are small 22.5mm diameter standoffs from a variety of sources available to mount a variety of items on the larger diameter drop bars, this does require some real customization as there are a number of factors involved (finger reach to external buttons, individual taste, size of display, etc.).
Personally I would instead of the All Axle motor consider a smaller lighter non thru axle hub motor (Shengyi SX or Bafang 310 or similar) and use the required small adapter nuts for mounting a QR hub in a thru axle dropout. This will also need some real customization to get everything to fit properly (additional spacers/washers, torque arm mounting, cassette position, disc brake rotor positioning, etc.). A torque sensing bottom bracket would also be appropriate, likely also requiring a different spider/crankset. I doubt anyone has this exact configuration so there won't be any guidance, it will require some serious trial fit work.
Assuming everything is mounted correctly you'd have a wonderful custom road/gravel bike with mild/moderate e assist. You wouldn't damage the bike's feel (same geometry, gearing and fit) but would be carrying 10-15lbs more in weight.
No external speed sensor, it's built into the motor
Wires usually go on the underside of the stay, and you try and color match the ties and wraps required. It's not going to be an invisible setup, you're really just trying to minimize the obvious changes.
Like most road bike conversions I would initially consider using a bottle style battery - these are usually available in the 300w range. Some bottle batteries also include space for a controller.
One alternative to the bottle style battery would be one of the smaller capacity Hailong battery cases with the integrated controller - typically in the 500w range. Visually this would however scream eBike. Mounting would be on the downtube and would likely require an offset mounting bracket such as the Grin triple Bob. This type of bracket would also add stability and strength to the battery and put less stress on the threaded attachment points.
Another battery alternative is a custom setup with a small frame bag, either below the top tube or a triangle bag. Visually quite stealthy but likely wouldn't be available with any certifications.
There are small 22.5mm diameter standoffs from a variety of sources available to mount a variety of items on the larger diameter drop bars, this does require some real customization as there are a number of factors involved (finger reach to external buttons, individual taste, size of display, etc.).
Personally I would instead of the All Axle motor consider a smaller lighter non thru axle hub motor (Shengyi SX or Bafang 310 or similar) and use the required small adapter nuts for mounting a QR hub in a thru axle dropout. This will also need some real customization to get everything to fit properly (additional spacers/washers, torque arm mounting, cassette position, disc brake rotor positioning, etc.). A torque sensing bottom bracket would also be appropriate, likely also requiring a different spider/crankset. I doubt anyone has this exact configuration so there won't be any guidance, it will require some serious trial fit work.
Assuming everything is mounted correctly you'd have a wonderful custom road/gravel bike with mild/moderate e assist. You wouldn't damage the bike's feel (same geometry, gearing and fit) but would be carrying 10-15lbs more in weight.
Last edited:
Tom@WashDC
Well-Known Member
- Region
- USA
- City
- Loudoun County, VA.
Easy to do. Just take your time. There is no magic to it. I did mine becuase the bike store said it would take them two weeks. I wanted to ride the next day.
JRA
Well-Known Member
Seems like you might be confusing straight pull spokes with spokes that aren't crossed and thus go straight from the hub to the rim and is popular on some hub motor/smaller wheel combinations? With larger rims using at least a 2 cross pattern is preferable. The Grin calculator mentioned is a good place to go.
Stefan Mikes
Gravel e-biker
- Region
- Europe
- City
- Mazovia, PL
The thru axle system has no dropouts. The compatible motor must have proper bearings installed inside it. Does such a motor also have a freehub body?
indianajo
Well-Known Member
You need to retake your physics course. Pay attention to units. Batteries do have a watt rating, but usually quoted in maximum amps. Different sizes of batteries come in wh rating - watthours.
QR hub motors are a good way to get one stolen in less than a minute. Require at least a $3 crescent wrench for removal of yours. Parked at stores, restaurants and on the street, I have lost some lights and tool bags. Never a $xxx motor or battery.
I install spokes with a screwdriver and a 6" crescent wrench. I set the tension by listening to the pitch when banged with a screwdriver. If the wheel is bent spokes on the far side will be higher in pitch than average, and visa-versa.
Broken spokes are mostly caused IMHO by imported grey metal instead of steel. Made of scrap containing copper zinc and lead. Unfortunately no US company makes 2.5 mm spokes.
Last edited:
Chargeride
Well-Known Member
Our local old school wheel builder wouldn't touch electric motors, but just a year later he's an expert.
Business is booming for him, mainly repairs, but lots of new builds as well.
Business is booming for him, mainly repairs, but lots of new builds as well.
The end of the stays where the axle is positioned is still often referred to by most folks as the dropout area even though there is no drop out capability.
The popular geared hub motors have a cassette compatible freehub, are usually sized fit into 135/7mm spacing and accept an HG 10/11 speed cassette. I don't know about compatibility with the slightly wider 12spd road cassettes on anything other than the Grin All Axle motor. The older hub motors often have freewheel compatible freehubs and are generally limited to 8/9 speed gearing, but on big DD motors you'll often see them with a single speed setup.
Stefan Mikes
Gravel e-biker
- Region
- Europe
- City
- Mazovia, PL
Rear thru-axle is either 12x142 mm or 12x148 mm for a road bike. The thru-axle hub is made with the outer bearings installed (it is the very concept of the thru-axle) and must accommodate a freehub body (not a freewheel).
Mahle X20 or X35 motor certainly have these capabilities. I'd like to see an aftermarket (non proprietary) hub motor that can be installed on a modern road racing bike.
No wonder the market has moved away from lightweight hub-drive motor road e-bikes in favour of mid-drives.
Mahle X20 or X35 motor certainly have these capabilities. I'd like to see an aftermarket (non proprietary) hub motor that can be installed on a modern road racing bike.
No wonder the market has moved away from lightweight hub-drive motor road e-bikes in favour of mid-drives.
Last edited:
You guys crack me up. There's no adaptor that would make a drop out hub motor work with a thru axle frame although there are adaptors for standard thru wheelhubs to work with drop out frames. And as I've posted before there is a torque sensing thru axle compatible aftermarket kit that works with 12x142mm frame and has 11 speed compatible free hub.
Watch it and weep. Keyde needs to send me a kit for testing and prove it to you. OP should post up what other after market thru axle compatible hub motors they found, maybe referring to a newly developed Swytch front wheel kit, not sure I'd use a front wheel motor on a carbon fork though.
Watch it and weep. Keyde needs to send me a kit for testing and prove it to you. OP should post up what other after market thru axle compatible hub motors they found, maybe referring to a newly developed Swytch front wheel kit, not sure I'd use a front wheel motor on a carbon fork though.
Stefan Mikes
Gravel e-biker
- Region
- Europe
- City
- Mazovia, PL
TREK went for Hyena hub drive motor for less expensive e-bikes. Domane+ AL looks like a proper road bike, not a DIY Frankenstein
More expensive road e-bikes get a TQ mid-drive motor.
I do hope so.
Mr. Coffee
Well-Known Member
- Region
- USA
- City
- A Demented Corner of the North Cascades
I think you are looking at a lot of work to produce a workable conversion in this situation. The multiple problems are all probably solvable, but they will take time and won't be cheap. And you likely will need to buy quite a few different parts and spend a lot of time patiently experimenting to get to something that will work for you.
What I'd do if I wanted to do a conversion like this is identify the go/no-go problems and figure out solutions, if any, that exist. That way you'll figure out if this is even possible and workable before you spend too much time and money.
The Big Two things I'd be looking at is identifying a suitable hub motor that will work with a thru axle and finding a stout enough rim that supports more spoke holes and still fits the frame.
I think running carbon hoops and not enough spokes with a motor is probably a Bad Idea.
What I'd do if I wanted to do a conversion like this is identify the go/no-go problems and figure out solutions, if any, that exist. That way you'll figure out if this is even possible and workable before you spend too much time and money.
The Big Two things I'd be looking at is identifying a suitable hub motor that will work with a thru axle and finding a stout enough rim that supports more spoke holes and still fits the frame.
I think running carbon hoops and not enough spokes with a motor is probably a Bad Idea.
Mr. Coffee
Well-Known Member
- Region
- USA
- City
- A Demented Corner of the North Cascades
If they can fit a tandem rim might be a good starting point. Also if they could fit a good MTB rim with 36 spokes, but I doubt they would fit your frame.
The downside to a tandem rim is that the rear wheel on most tandems isn't dished in and is symmetric and won't fit most singles.
Stefan Mikes
Gravel e-biker
- Region
- Europe
- City
- Mazovia, PL
Mission Impossible.
Did I mention converting a racing stallion into a mule? It is not a coincidence production racing e-bikes are so rare and expensive.
Did I mention converting a racing stallion into a mule? It is not a coincidence production racing e-bikes are so rare and expensive.
Similar threads
