Ebike motors for 110mm spacing

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Hey everyone. Has anyone put a rear ebike motor into a frame with 110mm spacing? I want to electrify my Heavy Duti and I'm looking for a rear hub that will fit the frame. Has anyone done this yet?
 
I bought a FRONT hub motor, already built up into a 26" 559 wheel, for a vintage bike conversion project. It was 100mm OLD, requiring some fork bending, but nothing that seemed excessive to me. I didn't find any rear hub motors that were narrow enough, especially since there was no provision for rim brakes on the machine I was working on.

The rear hub motors I was finding generally had provision for either cassette or freewheel on right side and disk on left, and started at around 135mm OLD.
 
I bought a FRONT hub motor, already built up into a 26" 559 wheel, for a vintage bike conversion project. It was 100mm OLD, requiring some fork bending, but nothing that seemed excessive to me. I didn't find any rear hub motors that were narrow enough, especially since there was no provision for rim brakes on the machine I was working on.

The rear hub motors I was finding generally had provision for either cassette or freewheel on right side and disk on left, and started at around 135mm OLD.
This is what I have seen as well. But many of them have a 7s freewheel, which fills up a lot of the 135mm of width. I don't have much experience with ebike hubs, but the other freewheel hubs I have seen have a spacer on the axle so that the lock nuts stick out of the freewheel. (As in the attached pic.) If I put a single speed freewheel on there, could I remove some spacers and skinny up the overall length? Get it closer to 110?

freewheel.png
 
This is what I have seen as well. But many of them have a 7s freewheel, which fills up a lot of the 135mm of width. I don't have much experience with ebike hubs, but the other freewheel hubs I have seen have a spacer on the axle so that the lock nuts stick out of the freewheel. (As in the attached pic.) If I put a single speed freewheel on there, could I remove some spacers and skinny up the overall length? Get it closer to 110?
I see what you are saying, and it seems like a good possibility. The freewheel end of this MXUS XF08 does look like perhaps there is a spacer secured with a locknut.

1673636815114.png

If you remove the nut and 1) the spacer is removable and 2) can be finagled over the electrical cable, and 3) the axle is threaded down far enough, it appears a possibility that you could get your OLD down into the neighborhood of 115 - 120 mm.

This MXUS motor is ~ $95 - $120, depending on the power rating. https://www.ebay.com/itm/254942749063
1673637076447.png

But unless you sever or remove the cable assembly and re-terminate it, you would still have a long protrusion sticking out the right side of the bike, which would be prone to accidental damage.

There are hub motors available with the cable on the opposite side. I would think that this would be an easier modification, if the construction facilitates what you are describing. unfortunately, I'm not finding any images detailing what is under the sprocket cluster.
1673637585408.png


There's one other possibility that I can think of. Attaching a sprocket to the 6 screw pattern for the brake disk provided on a FRONT wheel hub.
1673637954094.png

Not sure how viable this idea is, either mechanically, or electrically, since it would likely require the hub to operate in reverse.

Perhaps, if there is somebody dealing in e-bikes in your area, you could get some condemned hubs to investigate? I understand that replacing deceased hub motors is a pretty regular event in the e-bike world.
 
I'm sort of warming up to the idea of using a front hub. I think I have read about that elsewhere. You either need to find a compatible cover that has the freewheel threads on it or make an adapter and use the disc brake holes, and then run it in reverse. It's a DC motor, you can just reverse the +-, right? Or anyway that's what I learned in physics class in high school.

I stopped by the local eBike store today and they did not have any good 110mm options for me. They said they would convert my bike for ~$1400. They won't sell me the parts to do it myself. eBikes are crazy popular around here and I think they are having trouble keeping up with demand, so I totally get why they don't want to put a ton of effort into a one-off job like mine.

Not sure how viable this idea is, either mechanically, or electrically, since it would likely require the hub to operate in reverse.

Perhaps, if there is somebody dealing in e-bikes in your area, you could get some condemned hubs to investigate? I understand that replacing deceased hub motors is a pretty regular event in the e-bike world.
 
I'm sort of warming up to the idea of using a front hub. I think I have read about that elsewhere. You either need to find a compatible cover that has the freewheel threads on it or make an adapter and use the disc brake holes, and then run it in reverse. It's a DC motor, you can just reverse the +-, right?
I guess that some of the lower end hub motors are indeed simple two terminal brushed motors.

But more sophisticated bike hub motors use brushless 3 phase motors.

1673722865418.png


This allows much more control, better efficiency and longer life, with no brushes to wear out. This video describes the basic concept:


DC is chopped and pulsed into the 3 phases under control of the dedicated controller. The controller does the magic, including the speed control function. I'm not sure how reversing the direction of a brushless motor would be done, but I imagine it's done in the controller software. Here's wiring of a typical controller.
1673723607478.png


Brushed motor controllers will be simpler. Here's an example of a brushed motor controller:
1673724402837.png


It's still a lot of wiring to sort out. You'll want to make sure that the components you choose are compatible and will give you the result you expect.
I stopped by the local eBike store today and they did not have any good 110mm options for me. They said they would convert my bike for ~$1400. They won't sell me the parts to do it myself. eBikes are crazy popular around here and I think they are having trouble keeping up with demand, so I totally get why they don't want to put a ton of effort into a one-off job like mine.

E-bikes are definitely up and coming. I went with a front wheel kit (for front installation) to keep things simple for my first conversion, but it's actually been sitting on a shelf as other projects keep popping up.

If you aren't dedicated to the idea of converting a vintage bicycle, I'm thinking that one can actually get up and running for less money, and definitely less effort, by taking advantage of sales as manufacturers adapt to the emerging market. For example, when RAD discontinued their RadMission model last spring, they offered them up for $499, complete, with some assembly required. I seriously considered buying one, but the single speed hub put me off. Still, with its front and rear disc brakes, 500w motor, and lithium battery, that's a lot of stuff for the money, and they threw a bike in as well. Apparently other people thought so as well, as they sold out in about 5 days.

https://www.engadget.com/rad-power-bikes-radmission-electric-bicycle-review-120020625.html
 
If you aren't dedicated to the idea of converting a vintage bicycle, I'm thinking that one can actually get up and running for less money, and definitely less effort, by taking advantage of sales as manufacturers adapt to the emerging market. For example, when RAD discontinued their RadMission model last spring, they offered them up for $499, complete, with some assembly required. I seriously considered buying one, but the single speed hub put me off. Still, with its front and rear disc brakes, 500w motor, and lithium battery, that's a lot of stuff for the money, and they threw a bike in as well. Apparently other people thought so as well, as they sold out in about 5 days.

https://www.engadget.com/rad-power-bikes-radmission-electric-bicycle-review-120020625.html
This is good information! I guess I figured it was more complicated than just reversing + and -. Oh well.
 
Here's a kit that says it is for BMX and the spacing is specifically called out as 110mm. I am thinking I could buy this kit and lace the hub into my own rim. Does anyone have any experience with Leafbike?
Good find! This looks like just what you are looking for. Unlacing wheels and relacing to a new rim is a tried and true method of modifying the performance of a motor. For example, to violate the software imposed speed limit, lace the motor from a smaller wheel to a larger rim. (I know this isn't what you are going for here.)

It seems that Leaf Bike is the retail side of Leaf Motors. I'm finding what looks like the corresponding motor on Leaf Motor, but not the narrow "BMX" build.
https://www.leafmotor.com/48v-52v-1500w-rear-e-hub-electric-bike-motor-p00105p1.html
https://www.leafmotor.com/single-cog-p00143p1.html

The Leaf LMM481500R hub looks like a direct drive (no planetary gears), 3 phase powered design to me. According to this 3/22 review, it contains some refined features which improve torque and efficiency. https://www.electricbike.com/leafbike-1500w-hubmotor-the-mid-sized-hot-rod/

If you want to look at some basic discussion and options in hub motors, this article is a few years old, but covers a lot of the basics: https://ebikes.ca/getting-started/hub-motor-options.html

I've only been on Rad Rod Bikes for a few months, but I find it to be a great source of knowledge and folks are very willing to share. Still, for very specific detailed info like this, I'd probably seek out a forum more focused on electric bicycles. I won't link direct to another forum, but a Google search showed me that some folks communicating in a group called "Endless Sphere" have had experience with Leaf motors. There's lots of very detailed discussion of suitability and performance of various motors, including Leaf products there.

1500 watts is a pretty substantial 2 hp. USA legal definitions of electric bicycles limit them to half that, 750 watts. Most manufacturers use the controller to limit the power, and enforcement of these federal definitions affect manufacturers at this point, not riders who build their own. Still, things like the power and speed limits are there to protect the little guy from relying too much on his guardian angel. What plans are you making to upgrade braking capability on your Heavy Duti?
 
The Heavy has had a Worksman front drum hub for a decade or so. This contributes to my desire for a rear hub motor since there's no hole in the fork for a brake caliper. (Also contributing is the fact that I don't want to file open the fork to fit the larger diameter of an electric hub axle.)

The Bendix red band will be replaced by the hub motor and freewheel but this frame has a mount for a caliper for the rear wheel.
 
Ok this is interesting. I'm attracted to the chain drive but simultaneously repulsed by sprocket that clamps onto the spokes.

https://www.amazon.com/Newest-Electric-Conversion-Bicycle-Sprocket/dp/B0733CNV25?th=1
This guy talks about building and riding that rig on U-tube:



The clamp on rear sprocket has been the go-to method for adding a chinese two stroke gas engine for quite some time, and I understand it is one of the most common sources of problems. I heard of a few ways to improve the situation;
- Heavy duty spokes
- A sprocket that clamps on the hub. https://www.bikeberry.com/products/bbr-tuning-sprocket-adapter-assembly?_pos=1&_sid=ea8b58d0f&_ss=r
- One that mounts to the disc brake 6 bolt pattern https://www.amazon.com/CDHPOWER-Ada...-Bicycle/dp/B08N4VSCCY/ref=asc_df_B08N4VSCCY/

But most solutions will, once again, put you up against the 110 mm dropout width constraint.

The gear motor in the kit doesn't look as cheap as some, but it is a brushed motor, and I would expect those and the bearings to wear out at some point. The controller looks tiny. Read the reviews to get an idea what to expect.

It's even cheaper from Walmart: https://www.walmart.com/ip/Electric...-Motor-Motor-Controller-w-Freewheel/764867348

The easiest retrofit has gotta be a friction drive kit: https://www.clip.bike/
 
Hey everyone. Has anyone put a rear ebike motor into a frame with 110mm spacing? I want to electrify my Heavy Duti and I'm looking for a rear hub that will fit the frame. Has anyone done this yet?
You can find 120mm rear drop out kits and either cold bend the rear, or just sort of wedge it in there. The only ones I've found are kinda stupid expensive unfortunately
 
I guess that some of the lower end hub motors are indeed simple two terminal brushed motors.

But more sophisticated bike hub motors use brushless 3 phase motors.

View attachment 222081

This allows much more control, better efficiency and longer life, with no brushes to wear out. This video describes the basic concept:


DC is chopped and pulsed into the 3 phases under control of the dedicated controller. The controller does the magic, including the speed control function. I'm not sure how reversing the direction of a brushless motor would be done, but I imagine it's done in the controller software. Here's wiring of a typical controller.
View attachment 222082
Wowser E-Howser, Axeman... Where did you score these fine drawings & photos? I wanna save these to the Mechanics folder on hd, but has a wee bit of jonque happening here instead. Going to the site you found them might be mo beta. Thank you much.
Brushed motor controllers will be simpler. Here's an example of a brushed motor controller:
View attachment 222083

It's still a lot of wiring to sort out. You'll want to make sure that the components you choose are compatible and will give you the result you expect.


E-bikes are definitely up and coming. I went with a front wheel kit (for front installation) to keep things simple for my first conversion, but it's actually been sitting on a shelf as other projects keep popping up.

If you aren't dedicated to the idea of converting a vintage bicycle, I'm thinking that one can actually get up and running for less money, and definitely less effort, by taking advantage of sales as manufacturers adapt to the emerging market. For example, when RAD discontinued their RadMission model last spring, they offered them up for $499, complete, with some assembly required. I seriously considered buying one, but the single speed hub put me off. Still, with its front and rear disc brakes, 500w motor, and lithium battery, that's a lot of stuff for the money, and they threw a bike in as well. Apparently other people thought so as well, as they sold out in about 5 days.

https://www.engadget.com/rad-power-bikes-radmission-electric-bicycle-review-120020625.html
 
Hi @Cmdr Ronald, Sorry, I don't recall where I found them. After years of sitting in front of the magic box, I'm good at finding stuff, but RE-finding it, ... that's another story, which is why I think the cut and pasted pictures are better than a clickable links. The picture will stay HERE until an admin. needs the server space and deletes them, while clickable links only last as long as the server that hosts them.

Certainly, in this case, a Google search for "brushless bicycle motor", then a click on the "Images" tab, then a visual review of images linked to those words, was involved. Similarly, I may have started with "Two wire controller", or "brushed motor controller". One result often leads to another search, perhaps based on a brand name or a model number. The more you find out, the better and more specific your searches can be.

It's a deep & convoluted rabbit hole. Sometimes I can't find the same image just minutes later, when I realize its significance, because google is buffering the image and I'm not into the "actual" page, just a representation of an image on it within a google search, so there's no "history link" created to go back to.

If I want a picture from a site that doesn't want me to have it, I get the biggest image I can on screen, then press "Ctrl + Print Screen" buttons simultaneously, which "Copys" a screen grab image to my system buffer. Then I "Paste" that screen grab into Microsoft Windows Paint, trim it down to include only what I want, perhaps reformat with a smaller pixel count (so it's less likely to be culled by a forum admin) and use it that way. You could try that method.

If you want to take a deep plunge into electric bicycle technology, the Endless Sphere forum I mentioned is deep and wide and specializes in this topic.
 
wow you guys sure know your stuff on the E bike scene.
Myself would look at stretching the rear, a couple blokes on here have made some simple widening tools and nobody will notice.
I too are still looking at electric options for my big cruiser, but just a plain brushless motor driving a chain, so far my biggest hurdle is the cost of batteries.
 
I too are still looking at electric options for my big cruiser, but just a plain brushless motor driving a chain, so far my biggest hurdle is the cost of batteries.
The lithium batteries are not cheap, that's for sure.

For a project that is still sitting on a basement shelf, I spent ~$160 for a generic looking 48V, 10Ah lithium pack, accepting the fact that I'd have to come up with my own packaging. (Lots of folks will just put it in a duffle back, strapped to a rear rack) https://www.ebay.com/itm/294951875588

That's 480 watt-hours, so right at $0.30 / watt-hr in cost vs. capacity. It weighs about 5lbs, and measures 10.2 x 3.5 x 2.8inch. This sort of pack is about the cheapest type of Lithium Ion battery I found at the time I was looking.

The main stream of the industry has settled on lithium ion as the preferred technology, because it has high energy, light weight, and can handle high current output and fast recharge. Almost everything I've seen targeted for the US market will use some form of lithium battery pack. But the China market does have some bikes offered for sale with SLA batteries, sealed lead acid. I was thinking that these might actually be just as good for the short range commuting that I want to do.

This size (12V, 5Ah) SLA battery appears to repesent the lowest dollar / watt-hour cost.
1681225808494.png

They are pretty generic, used in a lot of emergency lighting, which brings the competive price down. We can get these for about $7/ea, which is $0.12 / watt-hour, less than half of the generic Lithium Ion battery cost. If I put 8 of them together, At least on paper, in 4S2P (4 in series, 2 parrallel strings) configuration, I'd have the same 48V 10Ah battery pack, and it would cost me only $56 ( plus shipping). But, it would weigh 28 lbs and be something like 22 x 3.5 x 3.75 inches of volume. A 48V, 5 Ah pack would be only $28, and 14 lbs, and might be adequate for my personal use. I like the fact that I have a modular battery. If one module goes bad, I could replace it without a lot of fuss.

The fly in the ointment is likely going to be that SLAs won't be able to deliver the current we want to draw. I believe the 5Ah rating is based on a 5 hour discharge, and probably takes the battery down to essentially zero. To get that 5 Ah rating, they must have been discharging at something like 0.20 amps. If we want to keep our cells healthy, we won't discharge them past about 50%, and if we discharge them at high currents, we won't get rated capacity. They might even be damaged by high currents. I'll need to explore this idea further.
 

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