What kind of Salvage motors should I look for?

[CONSIDERABLE SHOUTING]

Thanks to a free Sondors from a good friend I know that my first true "commuter" eBike will have to be a mid-drive and I have been steadily assembling the knowledge needed to make my first. In doing so I've come across people adapting the Fisher & Paykel motors from Washing machines and other such appliances- and the desire to use a free motor instead of a $400+ cyclone for my first build is pretty great. I've got some fabrication work underneath me from fixing cars, and my stepfather had worked at a bike shop building and assembling them for years- what i'm asking is, despite that I'm new is there a motor of some kind I should use or look out for as a good beginner mid-drive and way to learn them? Something other than these "Fisher & Paykel" washing machine boys? Thanks!

 

[amberwolf]

There are literally hundreds of thousands of motors you could use...but unless you're willing to live with whatever they happen to be capable of, and whatever you have to do to make them work on your system, you have to narrow it down by what you want to do with it and what you're willing to do to make it work, etc.

To know what you need for a motor, it's just like any other system:

--what kind of power do you need out of it, continously, and burst? (and how long a burst?)

This is so you get a motor that can drive you at the speed you want, and can acclerate at the rate you need to, without damaging it, and without having to come up with exotic cooling systems for it.


--What kind of space do you have available for it?

If you get a motor that is the wrong shape or size, you might not be able to pedal, or might have to ride bowlegged, or stick it up on the rear rack and run chains/etc around your frame via jackshafts to get a working chainline.

--How much weight are you willing to carry around?

If it's big and heavy, it'll make it harder to pedal the bike when you run out of power or something fails. Similarly it'll take more power to acclerate more mass, or go uphill, etc.

--How much DIY can you do?

If you have a shop full of machining tools you know how to use, it opens possibilities for a lot of motors you can't otherwise deal with, if all you've got is a hammer and hacksaw.


--What kind of drivetrain are you going to use from it's output to your system's input?

If the motor output can only be connected in certain ways, requiring major DIY to hook it into your drivetrain, it's much harder than if you can use standard off-the-shelf parts from existing drives / etc.


--What kind of budget do you have?

If you dont' have enough money you may have to live with some severe compromises between battery, motor, controller, and what you need them to do.


--What voltage system do you have in mind; what battery do you want to use?

If you need to run it all off a 12v FLA car battery, your choices are a lot more limited than if you can use a higher-voltage modern lithium battery of some kind, for instance. If you have a battery that can only output a certain amount of amps, you're limited to systems that won't draw more than that, which limits your motor choices. Etc.


And so on. We'd have to know more specifics about what *exactly* you want it to do, and how you want to go about it, to recommend much of anything.

Otherwise, best I can say is to look thru this section of the forum at the various DIY middrives people have made, or attempted to make, for ideas.

 

[CONSIDERABLE SHOUTING]

Amberwolf! I was hoping someone like yourself would reply! I know your Crazybike is a product of necessity, but I find it really inspirational all the same.
Yeah, I knew that the questions to ask we gonna be legion in scale and scope like that :wink: . I was hoping that there was going to be some kind of stickied thread somewhere detailing excellent motors to find and use, though considering the ease and cheapness of things like the Cyclone and BBS mid-drives I can understand why not. The problem is tho, I haven't worked on electronics outside of basic jobs like installing head units and LED lights, and while I have 'middling' fabrication ability I know enough to know that I could quickly turn a $400 Cyclone into an expensive paperweight- so I'm looking to make something with a basic motor without regen so I have more skills and knowledge when I tackle something more complex.

My hope and build will likely look something like this:

• Able to climb the 3 hills to my work, the worst at least 20% grade (with some about 25%).

• ~20 miles of total range. My job is 5 miles from my home, and I'll need the overhead for good battery health.

• Fat tires. My streets are poor and the sidewalks even worse, and here in the midwest I'm not gonna ride on streets because...

• Max speed 30-35MPH, and only for kicks. Driving the Sondors at 20-25MPH is fun, but it's also spooky on it's bashed rims and ruined tread. Even worse since our drivers are pretty bad and our streets are potholled. I'm gonna stick to sidewalks for safety and focus on torque.
  • Have some lights and gubbinz, for safety.
  
  So with motors like that Fisher & Paykel supposedly being 4KW and BLDC controllers being cheap as chips it makes me hopeful that I can achieve what I think are modest goals on a known motor like that one, or something else that someone has had luck with. But that's just what I think and I could be horribly wrong, so I'm hoping someone could drop some knowledge bombs on me or point me in some good directions.

 

[Grantmac]

I think by the time you buy all the accessories to make a salvage motor run as a mid-drive the Cyclone will seem like a reasonable price. It isn't great but it works and so long as you aren't running it full tilt it's reliable (I commute one).

 

[CONSIDERABLE SHOUTING]

I think by the time you buy all the accessories to make a salvage motor run as a mid-drive the Cyclone will seem like a reasonable price. It isn't great but it works and so long as you aren't running it full tilt it's reliable (I commute one).

Really? Becuase Lunacycle makes a note to claim its not for newbies- is that just for show?

 

[Grantmac]

Compared to a repurposed washing machine motor its a doodle. The stock mounting just needs some help.

 

[amberwolf]

Really? Becuase Lunacycle makes a note to claim its not for newbies- is that just for show?

That's likely because, as with at least some other middrive systems, it can require a fair bit of DIY to get it to fit and work on any particular bike.

So whatever you want to do with salvaged motors is going to be a lot harder and time consuming than setting up a Cyclone, or pretty much any other middrive kit.

The good news with any DIY is you learn by doing. I knew almost nothing about bicycles a little more than a decade ago, other than that I rode them all the time until they broke, and then I'd find another cheap one, and ride it into the ground.... I still don't know a huge amount, but I know enough to fix most stuff and DIY things I need to. I knew essentially nothing about ebikes, motors, controllers, batteries, etc., back then either, though I was an electronics and computer tech. Now, I know a fair bit, and again can fix or DIY a lot of things (and know that I would never again want to try to design a controller.... :lol: ).

I know your Crazybike is a product of necessity, but I find it really inspirational all the same.

And the powerchair motors I used in that are one of the easier high-torque motors you can use; many of them use frame clamps on the gearboxes for around 1" tube, so using an old ten speed bike or other 1"-ish frame means you can use that clamp to secure the gearbox to teh frame with that, and then just need an L brakcet to go up from that to another part of the frame to prevent twisting.

Then weld or bolt a sprocket on the hub that goes on the gearbox output shaft, and line it up with one of the chainrings on the cranks. Use a sprocket iwth enough teeth that combined with the other one on the chainring give you the right ratio for a comfortable crank speed when the motor is running at the speed you want it to, and can't go fast enough to throw your feet off the cranks at full speed.

It will then go as fast as you can pedal at that speed, dependign on the gear you shift to at the rear. (you may not have the option to shift the front anymore).

Catch is you are always pedalling, forced by the motor, and you can't pedal with the motor not running. The gearbox makes that impossible, unless it's one of the types with a lever to allow a powerchair to be pushed by hand (it disconnects the shaft from most of the gearbox internals). If you can machine a shaft adapter to use a freewheel on the motor input shaft, and use a freewheeling crank, then you might be able to make a setup that doesn't require pedalling and does allow pedalling easily without the motor--but the freewheels are a weak point, and something that breaks in lots of crank middrives of all different kinds.


But these are really cheap (powerchairs with two of them are $25-$50 at thrift stores, and can be found even free sometimes, motors available cheaply online, etc.), and being brushed are really easy to drive. Meant to run at 24v, 36v usually works ok as long as you monitor for heat, they're only meant for around 300-400w. Torque is enough to destroy bicycle components including bending frames and tearing wheels apart, depending on the gearing you choose.

Able to climb the 3 hills to my work, the worst at least 20% grade (with some about 25%).

If its' something the bike can manage by pedal power, a motor can do it too--if you gear it down low enough to not overheat it, whcih may mean riding up the hill at a very slow speed if the motor's not that great.

~20 miles of total range. My job is 5 miles from my home, and I'll need the overhead for good battery health.

That's mostly going to be up to your battery; this is the killer expense of any system. YOu can recycle old batteries of various types for the good parts they have, or build your own 18650 pack, etc., or use "old" automotive-grade cells (so far that's the best stuff I've used, just can be awkward to package on a typical bike).

Fat tires. My streets are poor and the sidewalks even worse, and here in the midwest I'm not gonna ride on streets because...

Fat tires won't help as much as you might expect at speeds like you're talking about. A full suspension bike with good suspension would.

Max speed 30-35MPH, and only for kicks. Driving the Sondors at 20-25MPH is fun, but it's also spooky on it's bashed rims and ruined tread. Even worse since our drivers are pretty bad and our streets are potholled. I'm gonna stick to sidewalks for safety and focus on torque.

Since sidewalks are typically going to limit speeds for a number of practical reasons to 5-10MPH, then a simple "26" fattire" bike with no suspension might work ok, and it also simplifies the motor system, as it doesn't have to do anything significant in the way of speed. The battery also doesn't have to deal with much, except on the hills.

If you really want 30-35PMH out of it, it's going to take more of a system and a bike to handle that. More of a battery, too.

Have some lights and gubbinz, for safety.

Lights are easy; see my trike thread for the 12v LED strips / etc I'm using there. Wturber and others also use these.

So with motors like that Fisher & Paykel supposedly being 4KW and BLDC controllers being cheap as chips it makes me hopeful that I can achieve what I think are modest goals on a known motor like that one, or something else that someone has had luck with.

Realistically, it's going to be a hell of a lot easier and probably cheaper to buy a $250 hubmotor wheel kit from ebay, than do any of the middrives you could do with that kind of money.

You *can* do a middrive almost completely for free, if you are really handy, and you are very patient, and keep looking thru stuff people throw away or give away on Freecycle / Reusit / Craigslist / etc. This is mostly how I build CrazyBike2's middrive system (and the bike itself).


You could even buy the hubmotor kit, rip it out of the wheel, and install it in the frame as a middrive. (there's a few threads on how that can be done; Rassy's trike is the simplest).

 

[CONSIDERABLE SHOUTING]

The good news with any DIY is you learn by doing.

Yeah, and my idea of salvaging was mostly because of that- the boys a Grassroots motorsports making track weapons on $2,000 also has given me some inspiration, much to my parent's chargin

And the powerchair motors I used in that are one of the easier high-torque motors you can use; many of them use frame clamps on the gearboxes for around 1" tube, so using an old ten speed bike or other 1"-ish frame means you can use that clamp to secure the gearbox to teh frame with that, and then just need an L brakcet to go up from that to another part of the frame to prevent twisting. (...) Torque is enough to destroy bicycle components including bending frames and tearing wheels apart, depending on the gearing you choose.

Good to know they're easily sourced, but low voltage. Sounds like it would be better off as a fun board or small project that a bike that I would want to use and drive daily.

If its' something the bike can manage by pedal power, a motor can do it too--if you gear it down low enough to not overheat it, whcih may mean riding up the hill at a very slow speed if the motor's not that great.

That's mostly going to be up to your battery; this is the killer expense of any system. YOu can recycle old batteries of various types for the good parts they have, or build your own 18650 pack, etc., or use "old" automotive-grade cells (so far that's the best stuff I've used, just can be awkward to package on a typical bike).

I've had a few SLAs kicking around here from past things, mostly electric toys that neighbors tossed out that we running about 7.5 volts after a charge- not good for most things, but great for a flathead motor with a 6 volt generator!

I've started to look for sources of used batteries but so far, most places seem to have rigid protocols set up around specific recyclers and most have given me a shrug- though your idea for medical equipment companies gives me a trail to follow.

Fat tires won't help as much as you might expect at speeds like you're talking about. A full suspension bike with good suspension would.

I thought so. Thankfully, it seems like a good chassis with a decent suspension shouldn't be *that* hard to scrounge.

Since sidewalks are typically going to limit speeds for a number of practical reasons to 5-10MPH, then a simple "26" fattire" bike with no suspension might work ok, and it also simplifies the motor system, as it doesn't have to do anything significant in the way of speed. The battery also doesn't have to deal with much, except on the hills.

If you really want 30-35PMH out of it, it's going to take more of a system and a bike to handle that. More of a battery, too.

Good to know, and kinda what I thought anyway. Getting as high as 30MPH was a stretch, though I put it in just as a possibility- I know all too well that I'd have to bulk up my safety gear and use moped/motorcycle tires if I did.

Realistically, it's going to be a hell of a lot easier and probably cheaper to buy a $250 hubmotor wheel kit from ebay, than do any of the middrives you could do with that kind of money.

You *can* do a middrive almost completely for free, if you are really handy, and you are very patient, and keep looking thru stuff people throw away or give away on Freecycle / Reusit / Craigslist / etc. This is mostly how I build CrazyBike2's middrive system (and the bike itself).

You could even buy the hubmotor kit, rip it out of the wheel, and install it in the frame as a middrive. (there's a few threads on how that can be done; Rassy's trike is the simplest).

Yeah, talking with you has been a great help- it sounds like I need to build a 'primary' bike for what I want and slap together a cheap one for 'prototyping' some of these ideas. I won't lie- that salvage motor idea was driven by a different person's dream whom is also into EBikes that I like, and part of my brain is running with the thought that there's a cheap-ass method of mechanizing people for nearly free as a kind of favor to our species. Doing that kid of thing has always been a dream of mine :wink:

I'll start poking around for parts, shouldn't be too hard when I already do that for cars. I know that i'll likely need stronger gears if I go for a mid-drive like a cyclone just due to the power levels; is there anything in particular I should look out for, like Shimano branded items and such?

 

[amberwolf]

Good to know they're easily sourced, but low voltage. Sounds like it would be better off as a fun board or small project that a bike that I would want to use and drive daily.

That depends on the bike and the usage.

I used CrazyBike2 as a cargo bike to haul me and heavy stuff, daily, with those powerchair motors. They got hot but not too hot, and had plenty of torque; I didn't need lots of speed, but could've geared it to get that if I'd wanted it. Might've taken two motors to handle the power above 20MPH or so, but below that it was enough to do what I needed. (so much torque, kept flexing frame and tearing up sprockets, breaking chains, and even destroyed a wheel).

I've started to look for sources of used batteries but so far, most places seem to have rigid protocols set up around specific recyclers and most have given me a shrug- though your idea for medical equipment companies gives me a trail to follow.

It might be tough to find used batteries that will still be useful, but there are sources out there. You can try advertising in Craigslist or ReUseIt or FreeCycle or similar, asking for any kind of old batteries (other than car lead-acid batteries), and then testing these for usability (recycling the rest). There's info on testing scattered around the forum. I'm sure there's enough people with old toolpacks and laptop cells and whatnot that you could eventually build a big enough battery to be useful. Alternately, check with the people on the forum that have built batteries from lots of recycled cells, and find out where they got theirs, to see if similar sources exist in your area.

I thought so. Thankfully, it seems like a good chassis with a decent suspension shouldn't be *that* hard to scrounge.

Or you can build one if you have to. Copy the geometry of something that woudl do what you want, with good suspension parts.

Good to know, and kinda what I thought anyway. Getting as high as 30MPH was a stretch, though I put it in just as a possibility- I know all too well that I'd have to bulk up my safety gear and use moped/motorcycle tires if I did.

Bike tires might still work fine, but the MC stuff is thicker and less likely to be punctured, which can make it safer for higher speeds in places that's a possibility.

However, it is a LOT heavier. I use fairly light moped tires/tubes but they are still way heavier than bicycle tires. I use them because of their puncture resistance *and* because they hold more air / are larger than bike tires that fit on the same rims, so they give the bakc of the heavy unsuspended trike a little bit of help against the fairly poor road edges around here, that I have to ride in most of the time.

Bicycle tires I wore thru or got punctures with way way too often (though they were mostly already used, or old, none were modern puncture-resistant types). These moped tires have had just two puncture flats that I recall, one of them on the first set when it was worn down past the tread.

Yeah, talking with you has been a great help- it sounds like I need to build a 'primary' bike for what I want and slap together a cheap one for 'prototyping' some of these ideas. I won't lie- that salvage motor idea was driven by a different person's dream whom is also into EBikes that I like, and part of my brain is running with the thought that there's a cheap-ass method of mechanizing people for nearly free as a kind of favor to our species. Doing that kid of thing has always been a dream of mine :wink:

I thought I was going to start helping people do that locally when I started it, but generally I found that even people that had NO transportation weren't interested, if it meant they would have to do anything themselves, especially if it meant they had to learn something. :/

So I just keep helping out here, with those that show they're interested in learning.

I'll start poking around for parts, shouldn't be too hard when I already do that for cars. I know that i'll likely need stronger gears if I go for a mid-drive like a cyclone just due to the power levels; is there anything in particular I should look out for, like Shimano branded items and such?

Not really--anything that's a major brand name will have good stuff and cheap stuff, but it's all still pretty close to the same capabilities. Mostly what you get with higher priced bicycle stuff is lighter weight for the same (or less) power handling, but that weight doesn't matter for an ebike; the motor power will make up for whatever you add in mass (by design).

I *do* recommend quality brakes, doesn't matter if rim or disc, as long as they're not the crappy stuff on walmart type bikes. Even those, for rim brakes at least, can be improved with better pads (koolstop) and better cable/housing, and/or a booster arch to fix a flexy fork or frame. Disc you can get Avid BB7s for reasonably cheap, sometimes as little as $40 or less when good sales happen, maybe twice that otherwise.

Learn to build and true your own wheels; it's a skill you won't regret having, it'll let you do a lot of experimenting you couldn't afford to otherwise.

If you can't already, learn to weld and braze, and build / modify frames / etc., because that will let you experiment even more. I can just about guarantee that you can build yourself a more perfect frame for your specific needs than you can buy anywhere, once you learn how, and why frames are built in certain ways.


When I started the CrazyBike project, and Recycle before that, I knew virtually nothing about bikes other than that I rode them into the ground most of my life. Sheldon brown's site taught me lots, along with other similar sites. But mostly, just getting lots of old bikes and taking them apart and rebuilding them....