unconventional ebike motors.

Skyler

100 W
Joined
Apr 18, 2023
Messages
136
Location
Alaska
I am always watching youtube videos where DIY ebikes are built from motors that were never supposed to power an ebike or any EV. Some are successful and some not so much. It is interesting though to see.

I have seen a few alternators used and even a washing machine motor. It is as simple as typing either of those with ebike after it and there you go.

I am posting this because I found a motor for about $100. My criteria is 24V. 12V would require 6 or 8 gauge wire to get decent power so will stick with 24V for this post. Nothing > 30V. The reason is I own super heavy lithium titanite. Lishen 18 Ah LTO. I ordered 24 back when stimuli's checks were sent out.

I did not really check for size and weight but went for performance only. I was a little disenchanted when hooking up 20 of them for 50V. It did work and have two e bikes I can run about 45 pounds of battery with when up to 20 miles of range is needed for a single charge. But what if only up to 10 miles is required or even less. > 90% of my trips are < 10 miles.

I decided to split my LTOs up into two separate packs. In series they will weigh about 50 pounds and are 55V @ 22S. The 10S 25V pack will weigh about 20 pounds. The 12S pack about 23 pounds. The 12S is actually two 6S packs in series so can mount them to either side of the triangle in a special built rack. Since they are so long they only work on a 26" or larger frame. The 10S 25V can fit on a 20" ebike on a rack on the top bar. I plan on building both. Kelly makes the perfect programable brush controller for both < $100

That is what has brought me here. The most powerful 24V ebike hub motor is only 250 watt. It also will cost about the same as a 48V 1,000W motor. The most powerful chain drive 24V is the 900 watt Currie which is 2600 rpm and about $112 before tax and shipping. For me I would want two of those with a single rear sprocket and Kelli mini controller. It is probably what I will go with but I really want to explore all alternatives.

Ampflow makes brush motors that will run 24V. However the rpms are way too high and would require expensive and complicated gear reduction. The price is also way too high.

Please feel free to post any links for cheap DIY 24V motors > 1,000W right here. I am looking at 1,500 + @ 24V and = < 4,000 rpm if possible. I have done extensive google searches and just found this today. It has the specs. I am looking for. Not sure about a controller and even if a motor sprocket could fit on it but with a machine shop it could be possible.


Please let me know.

Skyler.
 

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That's going to be extremely tough, the only real ebike motors i know of that run on 24v are cyclone mid drive motors, but they ain't great.

You're def gonna need to bring some higher voltage..
 
You’ll have to look beyond ebike motors. There’s some monstrous RC motors, down to around 120kV. No fun at all gearing them down, but it can be done.
 
Sorry, you were looking at direct driving the rear wheel rather than through the cranks? That makes the gear reduction easier, you need less than half as much of it.
 
Did you rule out hub motors?

I’ve little experience with direct drives, but imagine there’s suitable winds available. If not, you could easily commission a custom wound hub motor.
 
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You're def gonna need to bring some higher voltage..
Nope! Not for at least two builds. One 25V. The second 30V.

Two of those is probably what I will do on a heavy reinforced rear rack. It will sport a single 8mm chain to a single wheel sprocket.
Gearing will be around 36 mph as 1,800W total power. It will bo on a 20" bike.

The 30V will be a 26" frame with 24" wheels. I am thinking about two in the back and one up front.

900W / 24V = 37.5 * 30 = 1,125W 2 will = 2,250W. Three = 3,375W. Gearing for all three will be approximately 45 mph. It will be a race bike. The 20" will have a cargo basket up front and be a cargo bike. No front motor.

However I am still open to other motor options. For example some of those high power RC motors are low KV like in the 90 to 120 range.------------ 90 * 25 = 2,250 rpm @ 25V. 120 * 30 = 3,600 rpm @ 30V.

I always wanted a belt drive but need more choices for belts and pully options. Friction drive is out of the question. I don't want that.
It would be nice to do a hub but not seeing anything more than 250W. I thought they made 500W but not finding any.

This post is strictly for 24V motors. 30V being maximum. Any type of motor except AC unless a way to modify it to run DC. I think they did it with a washing machine motor.

washing machine motor for electric bike , alternator for ebike , RC motor for ebike.

The links would not post so if you type those in they are fun to watch.


Please share. Video links or any information is welcome here. Anyone interested or slightly curious. This post is not for beginners. looking for a simple conventional ebike. It is for folks NOT afraid to experiment.


If I do not find something better then will order the 900W Currie motors and Kelly controllers. Kelly makes brushless controllers also which might work with the RC motors.

you could easily commission a custom wound hub motor.

How much do you think and who does that ?? I would consider a 1,500W If cheaper than two 900W Currie motors or < $250.

Thanks for posting.

Skyler.
 
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I wouldn’t rush into this.

What you’re proposing is a very inefficient arrangement WRT to all of power, weight, money, and effort.

You should be looking at 1000-3000W hub motors. It’s simply a matter of finding a wind that will provide the power and top speed you require..

At least study the XYD-13 performance charts.

900w is pure dishonesty. Do not reward that seller by giving them your money.

20A is all that they can sustain. Beyond that, they cook.

Sorry for the severe tone I’m using. It’s for your own good, because you’re going in half-baked, and are about to bake some motors.
 
They gotta learn, they gotta cook their first motor and learn from their mistakes :bigthumb:;)
 
I don’t know. I cooked two at once, and it was a bitter blow. Three at once could be a crushing experience.

You’re right though, you definitely remember and learn from it.
 
Those are fairly heavy and very inefficient motors with a 1990's era design. You are probably not going to be happy with the range you get out of the completed build. I'd strongly recommend against choosing those motors.
 
Those are fairly heavy and very inefficient motors with a 1990's era design. You are probably not going to be happy with the range you get out of the completed build. I'd strongly recommend against choosing those motors.
If you are talking about the 900W Currie motor then you should know they have a 5 star rating I think.

900w is pure dishonesty. Do not reward that seller by giving them your money.

20 * 25 = 500W. Unite makes a 24V 500W motor which is 2,500 rpm. I was told that Currie motors are better than Unite motors.
20A is all that they can sustain. Beyond that, they cook.

Do you know anyone who cooked that exact Currie motor ?

I knew someone who had a 450W 24V Currie motor that was over volted to 675W 36V. It ran for three years and he sold it to his son who was too lazy to pedal and took it up a really steep hill. + he was like 270 pounds.

Currie has a decent reputation I thought. ?

Please provide more information on that if you can.

I previously ran the 500W Unite. It is bigger and heavier than the 900W Currie. However it is about half the price. A 500W Unite motor is around $60. The 900W Currie about $112. I could get three 500W Unite motors less than two Currie.

I wouldn’t rush into this.

Not rushing into anything. I have three 36V ebikes I run with custom built DIY LIFEPO4. I will soon have 55V 22S LTO but battery weight will be around 50 pounds. I will only run for 20 mile trips. For up to 10 miles I have 36V LIFEPO4. or 56V.

I can run 43V 13S and 56V 17S. However they have an expiration date. Maybe 500. more cycles. ? Not sure. I know they are about 50% or a little less capacity from running them. They leave here all about 75 to 85% most > 80% %. They come back from Wallmart at about 25 to 30% most being close to 30%. Looking at about 9 miles round trip. No full throttle. Maybe 23 or 24 mph normally.

Brand new A123 cells are 3.2 Ah. My DIY packs are all used from Battery Hookup. 8P. A123. New I bet they could do 20 miles easily.

I am looking at 24V options for next year. 2024. LTO batteries could be called forever batteries as they boast 50,000 charge cycles and 50 year shelf life. I did the homework on them. will start ordering 24V motors probably after Christmas or next year.

Thanks.

Skyler.
 
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'Tis NOT an 900W Currie..... the example below is purported 1000W Currie:

"...However, the Achilles' heel was the poor design choice of machining the end of the motor shaft into a helical gear. Even if the motor shaft was hardened and properly ground, it features the smallest load transfer surface and has the greatest potential to wear first..."

Currie1000wgearbox.JPG
 
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The link Papa posted is a good read. So are some of his other articles.

The finned aluminium can motors would come close to achieving the objectives. They were available on alibaba last time I looked. Still the wrong tool for the job though.

Anyway, good to hear that you’re allowing more time to find a better solution, and are open to different approaches.

The best advice I can give at this point is to spend the bulk of your research time between now and then analysing motor performance graphs. Find a single motor that’s powerful enough. Only look at motors >10lbs. Don’t exclude 36 or 48 motors. And if you’re struggling with interpreting the data, each time you find a motor of of interest, post links to the graphs here.

Your budget for this project is significant. You can achieve all that you want with it, but not if you squander resources on Kelly controllers and little brushed motors.

These motors have their place. I use them in scooters and lawnmowers, for short bursts. Then I get bored with them and power them to destruction. I’ve read about physical RPM limits of brushed motors, but it doesn’t agree with my experience. Little 70mm canned winch motors produce tremendous power at 12,000 rpm.
 
If you are talking about the 900W Currie motor then you should know they have a 5 star rating I think.

A 5 star rating doesn't change the fact that it's < 80% efficient and you have a lack of range already due to your chosen battery chemistry.
I would seriously consider a more modern and efficient motor.

There's another 10-15% range and much higher power waiting for you in a better, modern motor design. This would utilize your chemistry's strength ( power ) and also help make up for it's shortcoming ( range )
 

After reading that I think two of those motors will be fine on the back of the 20" bike.

As for three motors for a race bike NO. There is no reason for it when I own a 60V 3,000 watt brushless chain motor. That could be a race bike and I only need a sprocket and chain to build it.

The 900W currie motors will only see 25V of LTO. NOT 50 or 60V like in that post. Gearing will also be modest for 1,800W. 30mph should work fine as not many steep hills where I am.

peak / continuous A
KDS48100E24-48V60V100A60A

60 amps would only happen if I did go up a steep hill and could damage the motor. On the flat 1,000W should do 30 mph.

1,000W / 25V = 40 amps. 40 amps would probably cook a single motor but with two motors and one controller they should be ok.
Each motor would only do 20 amps @ 25V.

Those folk who did that post must have had $$$$$ to burn as they deliberately smoked motors. If I run them normally for a small cargo ebike it should last for many years. I wont be over volting with the Currie motors. If I want to do that I could use the larger heavier 500W Unite motors.

500W / 24V = 20.8V * 30 = 625W * 3 = 1,875W. YEA. No sense at all building that when I already own a 1,800W brushless motor on a 20" ebike in my basement with a flat tire.

In fact with two 900W Currie motors on a 20" cargo ebike gearing could be as low as 28 mph. I am not building it to go fast. It is for daily transportation so I can use 10S LTO which is about 20 pounds instead of 22S which is close to 50 pounds.

The only reason for building a second ebike 26" or larger would be the fact that I will have 12S LTO laying around collecting dust if I don't as would be running 10S exclusively for the ebike with the dual 900W Currie motors.

625W * 2 = 1,250W which is about perfect for 30 mph. Also the 24V - 500W motors are about half the price as the Currie motors.

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I might just order two of those and call it a day. I was just curious about the 900W Currie motors but being Curious is not a good reason to spend $$$$$. I could order a single 900W Currie motor and gear it as low as 26 mph and get a cheaper Kelly controller like this one.

The reason being if a 24V - 450W Currie ( the gear reduction model like in the old post I linked above) which was over volted to 675W and 26 mph lasted over two years before it burned out going up a steep hill. If that lasted that long then a 24V 900W motor geared for 26 mph should last 10 years.

peak / continuous A
KDS24050E12-24V30V50A30A

Either way I will probably order at least one Currie 900W motor and defiantly two 500W Unite motors. That is unless I find better 24V motors. think they used to sell 24V 500W hub motors but I only see 36V now. A 500W 24V front hub and Unite or Currie 24V rear chain would be a good idea so will keep looking.

Thanks.

Skyler.
 
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Funny, sad, and true.

I think you might’ve been a sports commentator in a previous life Calab.

Skyler, you’re letting a good story get in the way of the facts.

They’re 450w XYD motors. They use multiple codes for the same motors, seemingly for no good reason. XYD-13, XYD-6, and XYD-6D are the same thing.

Yes, two in parallel sharing 40A is an acceptable use case.

Your gearing is too high for it, but whatever, I’ll fight one battle at a time.

And yes, you could use a 40A Kelly. I don’t know what feature of the Kelly appeals to you though. The only one I’d pay for is torque throttle. Otherwise, yiyuns are the go to brushed controller, being five dollars each. You can parallel them for higher output.

The brushed Unite My1020s are capable of higher sustained power output, and can be run even harder with forced air injection.
 
They’re 450w XYD motors. They use multiple codes for the same motors, seemingly for no good reason. XYD-13, XYD-6, and XYD-6D are the same thing.

Thanks for clearing that up. I know Unite sells a 1800W 48V , A 2,000W 60V and 3,000W 72V brushless motor. I believe all three are the same motor so am not surprised

. nd yes, you could use a 40A Kelly. I don’t know what feature of the Kelly appeals to you though. The only one I’d pay for is torque throttle. Otherwise, yiyuns are the go to brushed controller, being five dollars each. You can parallel them for higher output.

Yes. That makes sense $$$$$$$ wise as for two 500W Unite motors price will be about $120 tax and shipping and only about $20 more for


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Thanks for the good advice. It is settled then unless someone posts something better. I could still use a link for any company that cold custom wind a hub motor for 1,000W or 1,500W @ 24V. That however would probably be very pricy. Probably > $300 as the gauge of wiring used would need to be thick even for silicone wire as

1,500W / 24 = 62.5 amps. A better fit for a 24V hub would be about 800 watts as

800W * 24 = 33.3 amps. Dual hubs front and rear could share the load easily with dual 30 amp controllers or even better a dual drive 24V controller for 30 amps * 2 for 60 amps. 60 ^ 25V LTO = 1,500 watts. Top speed would be 35 mph just like my 48V 1,500W kit on my full suspension bike. That will be powered by 50 pounds of LTO though. It wont be my daily commuter but only for 15 to 20 mile trips.

My daily commuter right now is a 36V 1,000W 3,000 rpm Unite motor with about 15 to 20 pounds DIY built LIFEPO4.

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The one I now have is #2. The first I over heated by running it at 8S - 20V LTO awhile back. I had one of those 2,000W 40 amp brush controllers. Once they over heat they smell and after that will over heat and smell at low throttle and normal operation. I just threw it and the bike out as was moving.


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The 36V 1,000W motor I am running now is hooked to an 800W 36V controller which is about 26 to 28 amps I would guess. It will easily hit 27 mph on the flat. Last week I left a 350 watt Bafang rear hub in the dust on the iron trail. A local bike trail.

It barley gets warm with that controller even at full throttle on flat but could melt up a steep hill.

I run 43V - 13S LIFEPO4 8P used A123 cells. 43V * 26A = 1,118W. Like I said earlier the A123 packs were used cells barley 70% capacity and I already put about 500 more cycles so looking at only 50% capacity soon then less. (recycle time)

It is why a dual 500W 24V ebike makes perfect sense as 10S 25V LTO will do 50, 000 cycles so will not need to recycle for 15 to 20 years. ( maybe never).

Thanks.

Skyler.
 
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Fair enough.

The MY1020 motors are by far a better option than the small XYDs if you have a place for them … which you do, the rear rack.

The controller you cooked was a good learning experience in false ratings. Take it to heart. Those styles are not only massively over-rated, they have no current limiting.

You need a current limiting controller in this application, with simplified throttle wiring. You’re not spoiled for choice. The Kelly is poor value for money. Yiyun own this market, and deservedly so.

Anyway, you’re having fun and learning along the way, and that’s largely what it’s all about.

However, if simple reliable cost effective performance is the main goal, then you really should be devoting your energies to the hub motor.

I’ve said it already, I don’t know much about the direct drives, but there’s likely a pre wound version to suit. Yes, a custom wind could be costly.
 
The controller you cooked was a good learning experience in false ratings. Take it to heart. Those styles are not only massively over-rated, they have no current limiting.

It was a 36V - 1,000W motor. Not the controller.

The one I now have is #2. The first I over heated by running it at 8S - 20V LTO awhile back

Those controllers can push > 40 amps as I tripped a 40 amp DC circuit breaker.

I have a 44T spoke sprocket my friend gave me who works on gas powered bikes. If I get two #40 8T motor sprockets and #40 roller chain the gearing will be

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It is not my first rodeo. I have run dual Unite motors and owned a 24V 500W motor. I ran it at 36V for 750W. It was on the back with a 36V 800W front chain. It ran 20 mph at 24V and about 32 mph at 36V. It was a few years back. The same bike now has my 1,800W brushless motor and set up for 55V of LTO.
Thanks.

However, if simple reliable cost effective performance is the main goal, then you really should be devoting your energies to the hub motor.

I have three 350W - 36V Bafang motors. Two on a vintage 26" DimondBack Outlook and one up front of a 700C Hybrid with a 36V 750W gear reduction chain on a stock 26" Currie dual drive hub with a 20T freewheel and geared for 24 mph @ 36V but run it at 43V and about 26 mph.

I have an old 36 / 48V 800W 20" hub motor that needs new spokes. 5 fell out due to rust. The sensor wires are intact but still going with a 1,000W sensor less or dual mode controller when I get the spokes fixed. Now imagine that on the front of the 20" bike with the 1,800W brushless motor on the back. with 55V LTO. HELL YEA !!!

Then as mentioned my brand new 1,500W hub kit. The 30 amp controller is cheap and only 9 mosfets I would guess so I installed a 48V 1,000W front chain with a custom chain tensioner. did not test the front motor but the hub did 33.5 mph on the flat awhile ago.
advertised speed was 35 mph.

Since then I found a 700C 1,500W kit that boasts 37 mph and a 45 amp 12 mosfet controller. It is < $220 but one super heavy ebike with a 1,500W kit is enough. I wont order that unless I can find or build a 16S LIFEPO4 pack that is about 20 Ah and < 20 pounds.

That is why I am looking at 24V for now and maybe that next spring.

The only reason for a 24V ebike is battery weight. 10S LTO = 20 pounds. 22S close to 50 pounds.

I even considered ordering that for all my 48V needs.

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It would work but that $$$$ is at least half what a decent 16S LIFEPO4 will cost. It probably weighs at least 5 pounds and due to heat I will see < 9 Ah with 10S 18Ah LTO after the conversion so not getting that. I want at least 20Ah for any 48V+ ebike.

24V 10S will be suitable for up to 10 miles of range. That is > 95% of my trips so a daily rider.


Thanks.

Skyler.
 
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Again, fair enough.

You’ve got experience and skills.

And weaknesses.

I’ll say it again. To progress you need a better grasp of motor performance. Ratings need to be understood, not taken at face value, and anecdotal evidence needs numbers to back it up.

Engineering and tinkering and experimenting are three different things. Two out of three is good.

But you mentioned “race” at least twice, and race bikes aren’t tinkered and experimented into existence, if you catch my drift. The design and construction can only be as capable as their creator. So if you have weaknesses, so will it.
 
Not unlike most members here (I suspect), I too succumbed to the 'Currie/Unite' Koolaid some 20 years ago. A learning experience to say the least, because most of my scooter finds were yard sales and trash-day discards - seemed like every other yard was littered with'um. Kids would leave them laying in front yards or driveways (with key usually on), doesn't take many repeats to deplete the cheap SLA batteries. And once dead, parents usually won't fund replacements. The itty-bitty motors were typically usable, but about a third were not. I ended converting my first gen trike, but it ultimately inhaled 3 of the damn things before I finally found one that survived about 4 months - I wasn't overly abusive either (especially after the first 2 rebuilds). Failures were largely due to a disturbing mixture of moisture, worn parts and atrocious QC. And, interestingly enough, none were were all that old. I just got tired of screwing with'um. All of my trikes since... have been BLDC... largely due to Justin's trip across Canada, and his acquisition of this amazing forum.

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ou need a current limiting controller in this application, with simplified throttle wiring. You’re not spoiled for choice. The Kelly is poor value for money. Yiyun own this market, and deservedly so.

I am not so sure about that.

What I do know is I am not sure I am interested in building a 27 mph cargo bike. I basically already have that. I am thinking about 1,500W and 35 mph gearing with 25V 10S LTO.

Two 24V 500W motors in the rear and one up front make 1,500W at 25V. Then a single Kelly controller can make all three work.

peak / continuous
KDS48200E24-48V60V100A60A

60 amps / 3 = 20 amps to each motor. 25V * 60 amps = 1,500W.

It should out perform my 1,800W brushless motor. That is because my 1,800W motor really is not 1,800W or at least not at 48V as advertised.

The downside is extra weight but the plus is much better heat dissipation than a single motor with similar power output. It should theoretically smoke the 1,800W brushless motor as way more amps.

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26amps * 48V = 1,248 watts.

1,800W / 48 = 37.5 amps. What it should be.

1800W / 26A = 69.2V.

It is possible for a brushless motor I guess.


The thing is when you ride it you will think it really is pushing 1,800W because it has so much more torque than a 1,000W brush Unite motor.

With old tired LIFEPO4 maybe 60% original capacity the 20" bike hit 32.5 mph at 56V but a lot of voltage SAG under load I would imagine. I think I did 32 mph with 50V of LTO and should hit 35 mph with 22S 55V LTO. I just don't feel like hauling around 50 pounds of batteries to do it though.

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Kelly offers much more than any cheap Chinese controller out there. Also they have factories in both the USA and China. Sales is in the USA as well .

Kelly is fully programable. I have not seen that before as I usually buy cheap controllers both brush and brushless. The only decent controllers I bought was a 1,000W 35 amp Greentime dual mode sensor less controller , My 1,500W 38 amp for my 1,800W motor. That and my 48 to 72V 3 kilowatt 70 amp controller.

None are programable though. The first two were in the $50 to $70 range. The 3 kilowatt about $130. That 60 amp continuous Kelly brush is about $90.

Since I wont be using a BMS a Kelly controller can be set to 20V for 10S LTO so the cells don't go below 2V. If I do use 30V or 12S LTO I should be able to set LVC to 24V. If not then I will have a multi meter on my dashboard. :D

Thanks.

Skyler out.
 
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This kind of motor might fulfill your criteria of unusual motors for bodging into a bike?
 
This kind of motor might fulfill your criteria of unusual motors for bodging into a bike?

Only if someone could make a motor sprocket for it. Also it is < 600W at 36V so would be a lot less at 25V.



What about this motor.


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I saw it awhile ago. Looks like a belt drive. By the looks of it I seriouslly doubt a motor sprocket would even fit on it. Also I doubt the pully can even be removed,

Any thoughts on how I could use two of those to power an ebike will be greatly appreciated. I might do it if I can get the parts needed for a reasonable price.

Please post any links. The performance of the motor looks like a perfect match for what I want to do.


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There is another one I saw. It says 12S max so that is 12S LiPo as I used to run LiPo and ran 12S. The question is could it run 25 or 30V or not. Also what controller would work.



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Is that the same as the 900W motor ?

They’re 450w XYD motors. They use multiple codes for the same motors, seemingly for no good reason. XYD-13, XYD-6, and XYD-6D are the same thing.

If that is true then which is it. 450W , 750W or 900W. The 900W is around $115. I could buy three of these 750W motors for the price of one 900W so if they are the same what am I looking at here ???? I am now confused on these XYD motors.

glennb Could you be more specific.​


I have studied these motors for years and get conflicting information like this.


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Here is more information on the XYD and Unite motors.


It seems like a lot of members have experience with these motors. Basically I don't care which combination of motors I use to achieve 35 mph minimum @ 25V LTO. $$$$$$$ is the main concern.

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What motor sprocket would work and who could make it ?

I am looking for the cheapest motors that can do the job and be reliable. If I can do it with two motors instead of three then that is better. Two 750W motors on the back is better than two 500W Unite motors on the back and one on the front.

I am not looking for all wheel drive for a cargo bike. I already have three all wheel drive ebikes. Two 36V and a 48V. A cargo basket on the back would not be possible or practical with two rear motors. Even if it could be done there would be way too much weight back there. A front motor would make a front cargo basket much more difficult not to mention front brakes.

If I have to I will do the two 500W motors on the back and one up front but would much rather get 1,500W at 25V on a reinforced rear rack and a cargo basket up front with normal mounted brakes under it.

Any feedback will be appreciated.

Thanks.

Skyler out.
 
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