What mid-motor might fit?

[Drizzt321]

So I tried a TSDZ2B, but won't fit unfortunately, anyone had another mid-motor that might work?

I could, potentially, mount something towards the back and use the left side of the dual-freewheel kit (www.tricycleconversionkit.com/tts) that I have to turn it into a trike to have a separate drive, just a plain single speed sprocket, and the regular chain pedal side would be separate. I found https://www.amazon.com/Electric-Brushless-Complete-Controller-Motorcycle/dp/B07HJBMKJK that could probably be made to work. Or maybe something like Amazon.com: LNUJIUN 48V 750W Electric Brushless DC Motor Kit with LED Display & Motor Controller 3-Wheel Bike E-Tricycle Brushless Motor Electric Bicycle Trike Conversion Kit for Adults Tricycle : Automotive. If the controller could be CAv3 compatible that'd be bonus, since I have one of those for my old front hub motor.

Or...I suppose mounting my front hub motor and getting a disc brake sprocket like Amazon.com: CDHpower Disc Brake Rotor Adapter and 28T sprocket for Gas Motorized Bicycle 48cc/66cc/80cc : Automotive and use that then. Hm.

 

[neptronix]

I've fit a lightest.bike mid drive to a middle bottom bracket like this. Because all the parts are modular, it's possible to fit odd situations like these.

 

[Drizzt321]

Gah, that website has some kind of insane, weird, annoying crap noise going on. But I'll look into it. Unfortunately doesn't look cheap

EDIT: Looking at it further, does look like it could work well. Unfortunately, it's far too expensive for me right now :/ Unless I can manage to sell off my TSDZ2B that I had bought, which I bought from Electric bicycles diy parts for e-bikes bafang cyc motors tong sheng which nicely flashed to OSF for me. But looks like a good kit, even if their site is a bit bonkers. And some of their videos a horrific AI generated "person" with absolutely shite dialog.

I'll keep looking around and keep this in mind. Unfortunately I also have a pretty short time limit before I'm going on the trip where I'll need this...

 

[neptronix]

Horrible website, bad software, fantastic efficiency, astounding power density, great fitment options, possibly very slow shipping.
I run an external sensorless controller on mine now and get 1600w peak out of it, and this also fixes the software issue.
Yes i'm hesitant to recommend it because it's a mixed bag.

There's also the revel propulsion kit, but it's 650w rated, heavier, and only works with a 36v battery. It also has a nice long distance from the BB to the motor.



There are a couple other mid drives with this kind of design.

 

[Drizzt321]

Horrible website, bad software, fantastic efficiency, astounding power density, great fitment options, possibly very slow shipping.
I run an external sensorless controller on mine now and get 1600w peak out of it, and this also fixes the software issue.
Yes i'm hesitant to recommend it because it's a mixed bag.

There's also the revel propulsion kit, but it's 650w rated, heavier, and only works with a 36v battery. It also has a nice long distance from the BB to the motor.
View attachment 373663


There are a couple other mid drives with this kind of design.

Another that probably could work, although I have a 48v battery, but that's easier to change batteries and have a working rest of the kit.

However, again, far more $$$ than I can manage right this moment :\

Might just be easier, and a lot cheaper, to get some of these flat dropouts Horizontal modular dropouts only - with/without eyelets and bolt through a plate/angle iron, and use that to clamp somehow to the frame. Or find someone to weld and cutoff the bottom from the old front fork I have around and weld it to a plate, and then some holes to bolt/mount to the back of the frame for my old front motor.

 

[amberwolf]

Is that a live-axle driving both rear wheels? If so, then a "simple" way to do things is to use "any" of the pedicab type drive kits, most of which are similar to the links you've given, and do what you describe in the first sentence.

The freewheels appear to be standard, as long as you get the six-spoke type.

If you can't get a freewheel with enough teeth for your application (whatever gearing ratio you require between motor and wheel size to not overload the motor at low speed or not provide enough top speed, etc), you can bolt larger sprockets to the teeth of the smaller one.

You can also do the same thing to mount a sprocket for a non-bicycle-chain size to the freewheel.


If you want to be able to change gears, there are some single-speed-width freewheels that have two sprockets on them, and a derailer could be setup for just those two using the lockout screws on it.


A cheap way, since you already have a hubmotor, is like you said: if it's in a wheel you can unlace it from the wheel, and use it's disc-mount to bolt a sprocket to instead, and use it to drive that input, like that other one you link. Those bolt-on dropouts would probably work, though you would probably stil want to use a torque arm on each axle end to be sure it doesn't have any issues.

Alternately, you can do mostly the same thing to drive your pedal chainline like Rassy did here, and keep your gear shifting capability.
Here's one trike he did this way; TerraTrike Rover, NuVinci N171B CVP his terratrike path thread is around here somewhere.

 

[Drizzt321]

So the rear is a double freewheel axle (TTS | tricycleconversion), with the left freewheel being a 24T sprocket (https://www.amazon.com/gp/product/B0F1FFK8BX). However, looks like I'll need to get it to reverse, since it's a front hub so the disc brake is on the left. I have a disc brake sprocket coming (32T to start with, can easily get a smaller one). Unfortunately I'm looks like I'm going to have to mess with swapping around hall sensor wires as well, not just phase wires. Very annoying..., but doable.

So I don't need as complicated a setup as you, since I'll have 2 chains. One for the regular pedals, and one for the motor to freewheel. But it is going to take some prototyping to figure out the best way to mount it in place, but I think I can do that.

Are you using aluminum or steel for all of your frame? I've got some 1/8" wall aluminum angle, that potentially could work fine. My only concern is keeping it from twisting with appropriate anti-torque measures.


Hmm....I have a geared front hub motor...that means I can't run it in reverse, right? Crapola.

 

[Drizzt321]

Hmm...I'm tempted just to buy https://www.amazon.com/Chokayaky-4500RPM-Electric-Motor-33A-Throttle/dp/B0DB4V655Q, even though it's overpowered. 500-750W should be just fine. But it'll get to me a lot sooner.

Although I could just get the bare motor Amazon.com: Kunray Electric Brushless DC Motor, 48V 2000W 4300RPM High Speed Motor Electric Scooter Bicycle Motorcycle Mid Drive Motor, DIY Part : Sports & Outdoors, and use my 48v 25a controller with it. Just hook up the phase & hall wires. And would need to set the phase & hall sensors the right way to have the output be the correct side, depending on how I'll be mounting it. Would be an easier mount, since it's got side holes to bolt to or appears to have a bottom 4 bolt holes.

The problem with all of this is the sprocket is pretty close to center line, and these are on the wide side.

Amazon.com: 48V 800W DC Brushless Motor Conversion Kit, Sine Controller for Electric Tricycle, Aluminum Alloy, DIY Motor Kit Motor Conversion Kit for Electric Tricycle Scooter 800W : Sports & Outdoors looks like it'd be great, but no clue what the physical size is, doesn't mention that *grumble*grumble*

I suppose I could just get a rear motor Amazon.com: Electirc Bicycle Gear Hub Motor, 48v 500w Rear Drive Configuration Motor, Brushless Rear Drive Waterproof Metal Electric Bike Hub Motor, for Bicycle Upgrade Parts : Industrial & Scientific and a single sprocket, so it'll be on the correct side out of the way of the chain. Or I'll need to add a jack shaft and sprockets, which if I'm doing that, I might as well just use my current motor.

I think I'll get https://www.amazon.com/pinkhatcat-Jackshaft-Minibike-Complete-Chain/dp/B0C58SDJX1, might need to cut down one end of the shaft to make it narrow enough to fit reasonably, and I think those sprockets will fit standard bike chain, seems likely. Guess I'll find out. And then I'll start cutting my aluminum angle I have laying around to at least prototype a mount for the motor, even if I don't end up using that. Might get Horizontal modular dropouts only - with/without eyelets and bolt those onto whatever mount, and use that for the to slide the motor into, and also use the torque arm I already have, somehow, to provide more strength.

EDIT: According to Wikipedia Bicycle chain - Wikipedia modern bike chain is #40 roller chain, which what I just bought will work with them. Excellent!

 

[maiz]

Horrible website, bad software, fantastic efficiency, astounding power density, great fitment options, possibly very slow shipping.
I run an external sensorless controller on mine now and get 1600w peak out of it, and this also fixes the software issue.
Yes i'm hesitant to recommend it because it's a mixed bag.

There's also the revel propulsion kit, but it's 650w rated, heavier, and only works with a 36v battery. It also has a nice long distance from the BB to the motor.
View attachment 373663


There are a couple other mid drives with this kind of design.

Also hasn't been in stock in quite a while.

 

[amberwolf]

So I don't need as complicated a setup as you, since I'll have 2 chains. One for the regular pedals, and one for the motor to freewheel.

I'm not sure what you mean about my setup? I don't use a middrive on my SB Cruiser trike, though the pedal drivetrain is rather complicated because of the IGH and the transfer axle, etc. The pedals have a triple chainring on the cranks, though the chain always stays on the granny gear. That chain feeds the input to an old Sachs IGH mounted in the frame. The IGH feeds the transaxle input via a second chain, from a sprocket I welded to the IGH flange. The transaxle then passes this to the left wheel's singlespeed freewheel input via a third short chain from it's output sprocket.

Because of my knees and other joints, I have the pedals geared very low, so its about 1mph or so but at least I *can* pedal it if I have to, for a short distance, in the event of complete system failure.

The motors themselves are twin hubmotors mounted in 20" rims, one on each side of the rear.

Are you using aluminum or steel for all of your frame?

It's all steel (because I can get it easy enough as scrap, and it's easy to weld), but it probably isn't all that likely to be applicable for your situation. But I use thick steel clamping dropouts to secure the hubmotor axles:

This is what it looked like before I created the clamping dropout. The Ubolt is there to prevent the axle from sliding down in the event of the nut working loose, because there are significant lateral forces on the wheels in turns, which can cause it to "yank" one end of an axle downward and let the wheel tilt in the frame, rubbing the tire on the frame. (ignore all the broken spokes, it was an attempt to use an OEM built wheel the motor came in; I never have that problem with my own built wheels).

Hmm....I have a geared front hub motor...that means I can't run it in reverse, right? Crapola.

If you are willing to open it up, you can disable the clutch in a number of ways, so that it will operate either way if necessary.

But depending on how you design the drivetrain from it, you don't have to run it reversed.

 

[Drizzt321]

I'm not sure what you mean about my setup? I don't use a middrive on my SB Cruiser trike, though the pedal drivetrain is rather complicated because of the IGH and the transfer axle, etc. The pedals have a triple chainring on the cranks, though the chain always stays on the granny gear. That chain feeds the input to an old Sachs IGH mounted in the frame. The IGH feeds the transaxle input via a second chain, from a sprocket I welded to the IGH flange. The transaxle then passes this to the left wheel's singlespeed freewheel input via a third short chain from it's output sprocket.

Because of my knees and other joints, I have the pedals geared very low, so its about 1mph or so but at least I *can* pedal it if I have to, for a short distance, in the event of complete system failure.

The motors themselves are twin hubmotors mounted in 20" rims, one on each side of the rear.
View attachment 373722



It's all steel (because I can get it easy enough as scrap, and it's easy to weld), but it probably isn't all that likely to be applicable for your situation. But I use thick steel clamping dropouts to secure the hubmotor axles:
View attachment 373717
This is what it looked like before I created the clamping dropout. The Ubolt is there to prevent the axle from sliding down in the event of the nut working loose, because there are significant lateral forces on the wheels in turns, which can cause it to "yank" one end of an axle downward and let the wheel tilt in the frame, rubbing the tire on the frame. (ignore all the broken spokes, it was an attempt to use an OEM built wheel the motor came in; I never have that problem with my own built wheels).
View attachment 373721





If you are willing to open it up, you can disable the clutch in a number of ways, so that it will operate either way if necessary.

But depending on how you design the drivetrain from it, you don't have to run it reversed.

I was talking about the picture you posted above of the tadpole.

 

[amberwolf]

I was talking about the picture you posted above of the tadpole.

Ok, well, as noted in that, it's Rassy's (I'm not Rassy, I'm Amberwolf, so it's not mine). I don't know anything about what it's made of; you'd have to check out whatever he posted in the thread(s) for it, or his other similar trike with similar drive method.

 

[Drizzt321]

Ok, well, as noted in that, it's Rassy's (I'm not Rassy, I'm Amberwolf, so it's not mine). I don't know anything about what it's made of; you'd have to check out whatever he posted in the thread(s) for it, or his other similar trike with similar drive method.

Oh, I totally didn't see that part, sorry. I was skimming fast, in a bit of panic mode, how the @#U() am I going to make this work?!!?!!

 

[amberwolf]

Been there, done that.

 

[amberwolf]

As for making it work, there are a lot of threads here with lots of ways to mount lots of differnet motors, and lots of ways to use them to drive the wheels, thru the pedal drivetrain or thru a different one. This subforum alone has probably hundreds of different ideas.

If it's helpful, I have several proposed middrive drivetrains in my Schwinn Trike conversion thread and it's drivetrain dev thread, though I haven't built anything for it yet, as I haven't decided on the final trike or drive design. Mostly it's dependent on what parts I already have, and what I can physically build with the tools I've got.

Help design a DIY middrive for this heavily customized trike

https://endless-sphere.com/sphere/threads/amberwolfs-schwinn-trike-rebuild-conversion-to-heavy-cargo-hauler.125947/ There are mulitple possibilities; I don't presently have a set design in mind, just a goal of being able to drive both rear wheels from the system, without preventing the pedals...

endless-sphere.com

Amberwolf's Schwinn Trike Rebuild / Conversion to Heavy Cargo Hauler

From here: https://endless-sphere.com/sphere/threads/the-sb-cruiser-amberwolfs-2wd-heavy-cargo-trike-dog-carrier.67833/post-1827806 I got an old Schwinn Tri-Wheeler Town and Country (probably the 1971 or 75 or 78 model, based on info from bikehistory.org) from someone I knew from the...

endless-sphere.com

 

[Drizzt321]

Well, prototype in PETG on my 3D printer, looks pretty solid and have some adjustments I can do as needed. I think the design is ready to send out to get cut for me. Hopefully a nearby place can get it done in the next few days, otherwise I'll send it out to SendCutSend: Custom Sheet Metal Fabrication

Anything major I'm not seeing? The pillowblocks and jack shaft will be mounted to the black extensions, probably drill through the 1" -1/8" wall tube to bolt through. They'll mount upside down to the bottom of it, and I think that'll give everything the clearance it needs. Or if I need, could probably have the shaft go to the right side a bit, and have the pedal go to it and stick a freewheel on it, and then another sprocket to go to the 7-speed gears. Probably not, but if I really end up needing to.

 

[Drizzt321]

What do ya'll think? Use spacers to lower the jack shaft so the pedal chain doesn't hit, or get a freewheel and remove the pawls to turn it into an idler and put it underneath the jack shaft on the idler?

The chain on the right/away from the camera is the regular chain for pedaling.

 

[amberwolf]

The idler will probably work better if you have less than perfect paths or roads. Otherwise, every little bump is going to slap the long chain into the stuff close to it.

You can use a simple old brake arm with a derailer jockey wheel bolted to it's cable lug point for an idler. The brake arm spring can be used to tension the idler against bumps.

The chain path can go above or below the idler--whichever puts less tension on the chain, or makes it less likely to jump off the idler in bumpy riding conditions.

Couldn't find the pics I saved of mine or aussiejester's, but its basically this

minus hte brakepad. Then take a derailer jockey wheel

and use the derailer's wheel bolt to secure it to the cable-end of the arm, in place of the cable-bolt/washer.

Then use whatever method works for your frame to use a brake arm bolt thru the regular brake arm's boss hole, with a bushing of the right size to fill it, or cut a brake boss off an old fork or frame and weld that to your frame. Or cut the entire section of frame tubing with the boss off, cut it in half lengthwise, then hose clamp that to your frame so the boss points in hte right direction for your brake arm idler. (this is what I did on CrazyBike2)



This page has some good tips about freewheel idlers if you need them

Idlers

Thru axles for bicycles are described, along with their advatnages and disadvantages

sheldonbrown.com

This page shows a derailer freewheel, but it doesn't use the mount and spring, so it's fixed.

Story of the hacky tandem

I've used the whole thing with just one of the jockey wheels so it can keep it's own tension. Pics are buried somewhere in the SB Cruiser thread.

 

[Drizzt321]

Good point about bumpy/uneven terrain, I definitely will be riding there. So I'll definitely need an idler. Removing the pawls from a freewheel will create a DIY idler that'll fit on the jack shaft, so I think that's what I'll do. Maybe even 3D print up a few guides I can glue on to help keep it on the sprocket if it jumps at all, which it probably will.

And good old Sheldon Brown link Followed his freewheel bearing rebuild, and it's basically what I thought. Do it like that, except remove the pawls. I have a 14T, I think that's nearly the smallest they go, so close enough. Probably will go under, since it's close-ish to the rear 7-speed, and want to make sure it pulls all the way to the top of the gears there. Hm. Unless I use spacers (which I'm already having made up on SendCutSend) to make the jack shaft a low lower, and then just make (3D print) a wider with top/bottom chain guide so that it won't flop down too far when bumps happen. This is the top part of the chain, so the drive part, so it'll probably only flop significantly when I'm not actually pedaling. But still, need to make sure it doesn't end up flapping against the jack shaft, especially since the shaft has a keyway so it could bang against the edges of that and get damaged.

 

[Drizzt321]

Ok, now that I've worked out the right size chains... here's the jigs/prototype of everything. Right now I have the freewheel I turned into an idler with the regular pedal chain underneath (silver sprocket at the far end), as that currently is the best configuration. Probably will change, might even not use it, because I'm going to be moving the jack shaft forward probably another 1.5-2", and using spacers to go down 0.5-1.5" most likely. I do have enough spacers coming to go down 2" in total if I need.

Once I get the parts (should be Wed, but I'm busy Wed evening unfortunately) from SendCutSend for both the motor mount and the spacers, I can do another test fit, and then paint everything before final assembly. Hopefully Thur or Friday. Then I get to test to see, with the rear held up in the air, if I can get things to work!

 

[Drizzt321]

Well...it fits, it works. Except for the fact that when the motor goes, the pedals go too, no freewheeling action! Uh oh...

Any thoughts? I might just need to be in PAS only :/

 

[amberwolf]

Well...it fits, it works. Except for the fact that when the motor goes, the pedals go too, no freewheeling action! Uh oh...

Is your motor input pre-freewheel? If so, that's going to happen; there's nothing to prevent the mtoor from backdriving the cranks.

If there is any freewheel between the pedal input and the motor, that shouldn't happen. If there isn't, then you can either use freewheeling cranks, so that even though the chain is backdriven from the motor and still moves with the motor, and so does the chainring, the pedals themselves don't (at least when your feet are on them--they're light enough to be backdriven even thru the freewheel without any load on them).

 

[Drizzt321]

Is your motor input pre-freewheel? If so, that's going to happen; there's nothing to prevent the mtoor from backdriving the cranks.

If there is any freewheel between the pedal input and the motor, that shouldn't happen. If there isn't, then you can either use freewheeling cranks, so that even though the chain is backdriven from the motor and still moves with the motor, and so does the chainring, the pedals themselves don't (at least when your feet are on them--they're light enough to be backdriven even thru the freewheel without any load on them).

Configuration is:
Motor, Jackshaft, Left single-speed freewheel.
Pedals, Right 7-speed freewheel

Left freewheel and Right freewheel are connected to each other (an interlocking nylon thingie, it's TTS | tricycleconversion). When the motor goes, it drives the Right freewheel forward, which in turn turns the pedals as if they are pedaling forward.

I just put on a freewheel on the jackshaft and connected the pedals to it. I can now have the motor go & the pedals don't move (e.g., like the rear wheels are spinning, without me pedaling).

I'm debating if I want to connect the jackshaft to the 7-speed (which is very close , so not sure the chain has enough deflection to shift very much), or just leave it on the single-speed. Probably the single-speed. Unless you can think of anything else where I can get everything working.

I was REAAAAAALY panicking, actually was just about to order a rim & spokes to lace the motor back to a front wheel, even if it wouldn't have as much grip/power since the weight is so far forward, most of it is towards the back. But now I have an option! Good enough for Burning Man, where going slow is actually the ideal. I might change out the sprocket from the jackshaft to the single-speed for a smaller sprocket, trying to get the motor to turn the wheels slower.

 

[amberwolf]

Configuration is:
Motor, Jackshaft, Left single-speed freewheel.
Pedals, Right 7-speed freewheel

Left freewheel and Right freewheel are connected to each other (an interlocking nylon thingie, it's TTS | tricycleconversion).

If theyre connected at the sprocket level, then they are essentially a single freewheel. If they are connected at the ratchet level, they are independent freewheels and one won't backdrive the other.

When the motor goes, it drives the Right freewheel forward, which in turn turns the pedals as if they are pedaling forward.

Is that with you on it, feet on the pedals? (if you're only testing offground, behavior can be different depending on system design).

I'm debating if I want to connect the jackshaft to the 7-speed (which is very close , so not sure the chain has enough deflection to shift very much), or just leave it on the single-speed. Probably the single-speed. Unless you can think of anything else where I can get everything working.

I don't know what you mean, for sure.

If you mean move the motor output to the pedal side freewheel input, so you can shift gears for it...the forward end of that chain has to be far enough forward to give enough lenght to prevent an angle that will cause chainlink binding, which adds friction, wastes energy, and causes excessive wear, and can cause the chain to catch on sprocket teeth and jump gears or come off. The distance has to be enough forward to allow a good angle for every gear you will shift into.

Good enough for Burning Man, where going slow is actually the ideal.

A co-worker that's going this year says that it's not just ideal, it's required. I dont' recall the speed limit she said but it was less than I used to walk at before my joints began to fail me.

I might change out the sprocket from the jackshaft to the single-speed for a smaller sprocket, trying to get the motor to turn the wheels slower.

you'll also get proportionally higher torque wit that lower speed, and load the motor down less. Ideally for acceleration you could set it up so the speed you will use it at is about 70-80% of it's actual max speed, so you get the same acceleration (ish) all the way up.

 

[Drizzt321]

If theyre connected at the sprocket level, then they are essentially a single freewheel. If they are connected at the ratchet level, they are independent freewheels and one won't backdrive the other.

They're connected at the sprockets, as per the images. Functionally they end up acting as 2 sprockets firmly attached to a shaft. Each sprocket is a freewheel, and the other side of the freewheel is to the 2 separate axles for each wheel.

I hadn't fully thought things 100% through...obviously.

Is that with you on it, feet on the pedals? (if you're only testing offground, behavior can be different depending on system design).

While it's with rear wheels off the ground, it is while holding the pedal to be sure. Worked fine.

I don't know what you mean, for sure.

If you mean move the motor output to the pedal side freewheel input, so you can shift gears for it...the forward end of that chain has to be far enough forward to give enough lenght to prevent an angle that will cause chainlink binding, which adds friction, wastes energy, and causes excessive wear, and can cause the chain to catch on sprocket teeth and jump gears or come off. The distance has to be enough forward to allow a good angle for every gear you will shift into.

Yeah, it's like 9.5" from center-to-center from the jackshaft to the center of the 7-speed. And I think going more than 2 or 3 sprockets will be a pretty far angle, so not a good idea.

A co-worker that's going this year says that it's not just ideal, it's required. I dont' recall the speed limit she said but it was less than I used to walk at before my joints began to fail me.

Yeah, looks like probably going to be a lot of dust piles all over the place *shrug* We'll see how it all ends up. 2WD is definitely going to be helpful.

However, I really need to figure out configuring the CAv3 so that the throttle isn't so touchy, I need a much lower 'gain', so it's so much power with just a tiny bit of throttle. Likewise on my cadence PAS, first time using one, and it just seems to go to full throttle when it turns on, not just a little bit of help. Any recommendations on that?

you'll also get proportionally higher torque wit that lower speed, and load the motor down less. Ideally for acceleration you could set it up so the speed you will use it at is about 70-80% of it's actual max speed, so you get the same acceleration (ish) all the way up.

Torque is good, but I need to get the wheels spinning slower too, so I go slower. The official speed limit is 5mph, although bikes/trikes 5-10mph is just fine, just so long as I'm not going crazy with the speed and keeping an eye out.