Using many small electric motors.

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Using many small electric motors.

Geopilot
Has anyone taken the approach of using many small electric motors to
build an electric vehicle?

By MANY I mean MANY.

Not 2 or three.

Like say 10 to 50 per wheel.

For example I have thought one way to start an electric vehicle project
at low cost would be start a three wheeller with strong frame but little
external covering (like the wrightspeed) and build a single gear
flywheel or geared power wheelwith multiple attachments points around
the perimeter gear for multiple motors so they could be added as
afforded or scavenged.


Several reasons/advantages of this design philosophy are.

1.Cheaper to build in stages. You can have a rolling working vehicle
with one or ten smaller motors andthen upgrade performance as you add
motors.
2. Individually wired small moters with separate batteries means
batteries can be charged separatley using lower amp equipment and small
wires.
3. More reliability - if one motor and or its battery burns out you have
49 more.
4. You can control all the motors with one control circuit and still
have amps for all circuits be low.
5. All parts can be lower cost and purchased for normal mass production
sources for electronics (although there are more of them) because each
part takes lesss amps.
6. as you ad motors you can add more shell weight to enclose vehicle
(because you built the frame strong to handle future expansion.)
7. You can run a few motors at high rpms if you want to change power or
efficiency and then if you need more power use all the motors - on the
fly!
8. Cooling many small motors might be easier than one large one.
9. Most small dc motors are also generators so braking recapture is
easy.

10. I might be able to recharge all batteries at once by designing a
system to spin the power wheel on a jack with the drive motors all
connected thus recharging all individual motor battery circuits at home
without having to explicitly design a sequenced charger for each motor
battery circuit.

Now I realize there are many drawbacks so no one need to point them out
endlessly and make THAT the primary subject of this thread. That's not
the reason I am doing this. Incrementable building cost is the KEY issue
for me as I want SOME kind of electic vehicle that will run - even if
poorly- from day one until I can add capacity.

ONE question I am trying to work out is how many toy motors would it
take to allow a framed trike to run at 30 mph on level flat surface
streets.
Who can chime in one that?

I want a three wheeler on the road I can build in the backyard. This for
me is the only realistic way to do it for a number of reasons too
numerous to go into.

I just wondered if anyone has tried this approach.

It is basically what the new tesla did with batteries for their supercar
(hundreds of tiny mass market batteries) except I want to do it with
batteries AND motors.

Also I have been trying to compute the power to weight ratio and
efficiency of say 100 toy electric motors compared to one big car
electric motor.

Anyone want to help firgure it out?

I am thinking 10 to 50 toy electric motors per power wheel depending on
which motors turn out to be best cost/power/weight/efficiency ratio.
Eventually all three wheels could be power wheels allowing all kinds of
special control of course but initially just one.

The goal is to get it rolling not perfection! Don't waste time telling
me how it won't be perfect!

PLEASE waste time with calculations of how many motors it might take or
any websites you find that have motors that might useful.

My goal would be cheapest incremental cost at first and not performance
but of course that could change as I build it adding higher performance
motors later. That is the whole beauty of the design philosophy. I can
add groups of motors and batteries for increased performance literally
$20 at a time.

The thing is while even surplus big ev motors rarely sell for super
cheap prices there are OFTEN huge over runs on mass market toy electric
motors with incredible discounts -sometimes boxes of hundreds of motors
for $20 bucks etc. We are talking pennies a motor sometimes.

And while I neverdue to lack of experince build a huge amp system - I
have NO problem wiring 50 small motors with one rechargable battery each
and one cheap variable control each and one mini plug each for
recharging and mechanically linking all 50 variable controls to one
handle so I can control all motors at once. And there is no
electrocution dangers.

Or controlling each with a transisitor and wiring all the transistors
together. I could even control them with a light system with a whole
bunch of ir tuned receivers leds on each motor circuit all responding
from the vairable output of one ir led all enclosed in a
box.(possibilites are endless)

I have been trying to get reliable small motor power info on the cheaper
toy motors but it is hard to find. Anyone who finds that info please
post!

Some of the more expensive electric rc airplane and car motors have
incredible power to weight ratios but they tend to be more expensive.

I just want a good price and power numbers for analysis.

Thoughts and

SPECIFIC NUMBERS for analysis wanted.

Www.Ikickgas.com


www.GlobalBoiling.com for daily images about hurricanes, globalwarming
and the melting poles.

www.ElectricQuakes.com daily solar and earthquake images.

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Re: Using many small electric motors.

gottdi
Go for it! When you have  a working model be sure to show it off. We  
would all love to see it go. The idea is worth at least a try. Don't  
continue to talk, go build it.

Pete  :  )



On Dec 22, 2007, at 7:07 AM, GWMobile wrote:

> Has anyone taken the approach of using many small electric motors to
> build an electric vehicle?
>
> By MANY I mean MANY.
>
> Not 2 or three.
>
> Like say 10 to 50 per wheel.
>
> For example I have thought one way to start an electric vehicle  
> project
> at low cost would be start a three wheeller with strong frame but  
> little
> external covering (like the wrightspeed) and build a single gear
> flywheel or geared power wheelwith multiple attachments points around
> the perimeter gear for multiple motors so they could be added as
> afforded or scavenged.
>
>
> Several reasons/advantages of this design philosophy are.
>
> 1.Cheaper to build in stages. You can have a rolling working vehicle
> with one or ten smaller motors andthen upgrade performance as you add
> motors.
> 2. Individually wired small moters with separate batteries means
> batteries can be charged separatley using lower amp equipment and  
> small
> wires.
> 3. More reliability - if one motor and or its battery burns out you  
> have
> 49 more.
> 4. You can control all the motors with one control circuit and still
> have amps for all circuits be low.
> 5. All parts can be lower cost and purchased for normal mass  
> production
> sources for electronics (although there are more of them) because each
> part takes lesss amps.
> 6. as you ad motors you can add more shell weight to enclose vehicle
> (because you built the frame strong to handle future expansion.)
> 7. You can run a few motors at high rpms if you want to change  
> power or
> efficiency and then if you need more power use all the motors - on the
> fly!
> 8. Cooling many small motors might be easier than one large one.
> 9. Most small dc motors are also generators so braking recapture is
> easy.
>
> 10. I might be able to recharge all batteries at once by designing a
> system to spin the power wheel on a jack with the drive motors all
> connected thus recharging all individual motor battery circuits at  
> home
> without having to explicitly design a sequenced charger for each motor
> battery circuit.
>
> Now I realize there are many drawbacks so no one need to point them  
> out
> endlessly and make THAT the primary subject of this thread. That's not
> the reason I am doing this. Incrementable building cost is the KEY  
> issue
> for me as I want SOME kind of electic vehicle that will run - even if
> poorly- from day one until I can add capacity.
>
> ONE question I am trying to work out is how many toy motors would it
> take to allow a framed trike to run at 30 mph on level flat surface
> streets.
> Who can chime in one that?
>
> I want a three wheeler on the road I can build in the backyard.  
> This for
> me is the only realistic way to do it for a number of reasons too
> numerous to go into.
>
> I just wondered if anyone has tried this approach.
>
> It is basically what the new tesla did with batteries for their  
> supercar
> (hundreds of tiny mass market batteries) except I want to do it with
> batteries AND motors.
>
> Also I have been trying to compute the power to weight ratio and
> efficiency of say 100 toy electric motors compared to one big car
> electric motor.
>
> Anyone want to help firgure it out?
>
> I am thinking 10 to 50 toy electric motors per power wheel  
> depending on
> which motors turn out to be best cost/power/weight/efficiency ratio.
> Eventually all three wheels could be power wheels allowing all  
> kinds of
> special control of course but initially just one.
>
> The goal is to get it rolling not perfection! Don't waste time telling
> me how it won't be perfect!
>
> PLEASE waste time with calculations of how many motors it might  
> take or
> any websites you find that have motors that might useful.
>
> My goal would be cheapest incremental cost at first and not  
> performance
> but of course that could change as I build it adding higher  
> performance
> motors later. That is the whole beauty of the design philosophy. I can
> add groups of motors and batteries for increased performance literally
> $20 at a time.
>
> The thing is while even surplus big ev motors rarely sell for super
> cheap prices there are OFTEN huge over runs on mass market toy  
> electric
> motors with incredible discounts -sometimes boxes of hundreds of  
> motors
> for $20 bucks etc. We are talking pennies a motor sometimes.
>
> And while I neverdue to lack of experince build a huge amp system - I
> have NO problem wiring 50 small motors with one rechargable battery  
> each
> and one cheap variable control each and one mini plug each for
> recharging and mechanically linking all 50 variable controls to one
> handle so I can control all motors at once. And there is no
> electrocution dangers.
>
> Or controlling each with a transisitor and wiring all the transistors
> together. I could even control them with a light system with a whole
> bunch of ir tuned receivers leds on each motor circuit all responding
> from the vairable output of one ir led all enclosed in a
> box.(possibilites are endless)
>
> I have been trying to get reliable small motor power info on the  
> cheaper
> toy motors but it is hard to find. Anyone who finds that info please
> post!
>
> Some of the more expensive electric rc airplane and car motors have
> incredible power to weight ratios but they tend to be more expensive.
>
> I just want a good price and power numbers for analysis.
>
> Thoughts and
>
> SPECIFIC NUMBERS for analysis wanted.
>
> Www.Ikickgas.com
>
>
> www.GlobalBoiling.com for daily images about hurricanes, globalwarming
> and the melting poles.
>
> www.ElectricQuakes.com daily solar and earthquake images.
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev

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Re: Using many small electric motors.

Bob Rice-2
In reply to this post by Geopilot

----- Original Message -----
From: "GWMobile" <[hidden email]>
To: "Electric Vehicle Discussion List" <[hidden email]>
Cc: <[hidden email]>
Sent: Saturday, December 22, 2007 10:07 AM
Subject: [EVDL] Using many small electric motors.


> Has anyone taken the approach of using many small electric motors to
> build an electric vehicle?
>
> By MANY I mean MANY.

>  Well, yes. OFF the Electric Car thing a tad, Trains, like we have in the
> Least Coast, a 10 car Metro North Commuter train sports one 185 hp series
> DC motor for EVery axle. Antrak 8 motors, AC for Acela Express, 4 BIG ones
> on a AEM-7 locomotive. Hundred years ago the Pennsy went with one BIG ass
> DC series motor in the body of the loco, commected to the wheels with
> siderods,counter balances, like a steamer, very picturesque at speed!

    Of couse space and weight isn't a big issue on trains, and being run on
'stench cords.( over head wires.) Oh, it's one of lifes pleasures cranking
on the power and seeing almost no sag on a 25k volt overhead as you help
people make up their minds where they are going to sit<G>!The modern trains
are a maze of electronics to control multiple motors, money is relatively
little object here. Trains are a VERY expensive hobby! Not to mention the
mechanical complexity of multiple motors on a road vehicle.

   For YEARS, in my deformatibve EV years I went with two motors, one for
each rear wheel. It was natures' most perfect differential! Far as I know
one of my examples COULD still be running around in Central Taiwan, where I
sold it. Mr Lee? Got yur ears on<g>?Ha Ha "Lee" is the most common Taiwanese
Surname.I'm sure the batteries are shot by now?

    Nopwadaze with good Zillas and whatnot, it simplifyes the car's
construction, for the Rest of Us. For a grocery getter, go fur car, one
motor works fine.

> Not 2 or three.
>
> Like say 10 to 50 per wheel.

> Horrors!Checking EVERY motor, IF it were DC??

> For example I have thought one way to start an electric vehicle project
> at low cost would be start a three wheeller with strong frame but little
> external covering (like the wrightspeed) and build a single gear
> flywheel or geared power wheelwith multiple attachments points around
> the perimeter gear for multiple motors so they could be added as
> afforded or scavenged.
>
    I guess?

> Several reasons/advantages of this design philosophy are.
>
> 1.Cheaper to build in stages. You can have a rolling working vehicle
> with one or ten smaller motors andthen upgrade performance as you add
> motors.
> 2. Individually wired small moters with separate batteries means
> batteries can be charged separatley using lower amp equipment and small
> wires.
> 3. More reliability - if one motor and or its battery burns out you have
> 49 more.
> 4. You can control all the motors with one control circuit and still
> have amps for all circuits be low.
> 5. All parts can be lower cost and purchased for normal mass production
> sources for electronics (although there are more of them) because each
> part takes lesss amps.
> 6. as you ad motors you can add more shell weight to enclose vehicle
> (because you built the frame strong to handle future expansion.)
> 7. You can run a few motors at high rpms if you want to change power or
> efficiency and then if you need more power use all the motors - on the
> fly!
> 8. Cooling many small motors might be easier than one large one.
> 9. Most small dc motors are also generators so braking recapture is

> easy.

>  You'd have a rat's nest of motors , controllers, wiring! Any room left
> over for passengers, freight?


> 10. I might be able to recharge all batteries at once by designing a
> system to spin the power wheel on a jack with the drive motors all
> connected thus recharging all individual motor battery circuits at home
> without having to explicitly design a sequenced charger for each motor
> battery circuit.

     A mechanical nightmare, thou.

> Now I realize there are many drawbacks so no one need to point them out
> endlessly and make THAT the primary subject of this thread. That's not
> the reason I am doing this. Incrementable building cost is the KEY issue
> for me as I want SOME kind of electic vehicle that will run - even if
> poorly- from day one until I can add capacity.
>
> ONE question I am trying to work out is how many toy motors would it
> take to allow a framed trike to run at 30 mph on level flat surface
> streets.
> Who can chime in one that?

>   But your "unused" motors are a drag, unless you have a mechanical
> disconnect. MORE complexity!

> I want a three wheeler on the road I can build in the backyard. This for
> me is the only realistic way to do it for a number of reasons too
> numerous to go into.
>
> I just wondered if anyone has tried this approach.
>
> It is basically what the new tesla did with batteries for their supercar
> (hundreds of tiny mass market batteries) except I want to do it with
> batteries AND motors.

        Easier with a zillion cells; you solder them together ONCE and they
go for the ride,.
>
> Also I have been trying to compute the power to weight ratio and
> efficiency of say 100 toy electric motors compared to one big car
> electric motor.
>
> Anyone want to help firgure it out?
>
      Nice Try! Not meaning to "Diss" you, it shows creative thinking. God!
We need it nowadaze!

> I am thinking 10 to 50 toy electric motors per power wheel depending on
> which motors turn out to be best cost/power/weight/efficiency ratio.
> Eventually all three wheels could be power wheels allowing all kinds of
> special control of course but initially just one.
>
> The goal is to get it rolling not perfection! Don't waste time telling
> me how it won't be perfect!
>
> PLEASE waste time with calculations of how many motors it might take or
> any websites you find that have motors that might useful.
>
> My goal would be cheapest incremental cost at first and not performance
> but of course that could change as I build it adding higher performance
> motors later. That is the whole beauty of the design philosophy. I can
> add groups of motors and batteries for increased performance literally
> $20 at a time.
>
> The thing is while even surplus big ev motors rarely sell for super
> cheap prices there are OFTEN huge over runs on mass market toy electric
> motors with incredible discounts -sometimes boxes of hundreds of motors
> for $20 bucks etc. We are talking pennies a motor sometimes.

     And that's about what they are WORTH! They would wear out and die by
the dozens!

>
> And while I neverdue to lack of experince build a huge amp system - I
> have NO problem wiring 50 small motors with one rechargable battery each
> and one cheap variable control each and one mini plug each for
> recharging and mechanically linking all 50 variable controls to one
> handle so I can control all motors at once. And there is no
> electrocution dangers.
>
> Or controlling each with a transisitor and wiring all the transistors
> together. I could even control them with a light system with a whole
> bunch of ir tuned receivers leds on each motor circuit all responding
> from the vairable output of one ir led all enclosed in a
> box.(possibilites are endless)
>
> I have been trying to get reliable small motor power info on the cheaper
> toy motors but it is hard to find. Anyone who finds that info please
> post!
>
> Some of the more expensive electric rc airplane and car motors have
> incredible power to weight ratios but they tend to be more expensive.
>
> I just want a good price and power numbers for analysis.
>
> Thoughts and
>
> SPECIFIC NUMBERS for analysis wanted.

    OK ya got them above.

    Seeya

     Bob
>

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Re: Using many small electric motors.

Dan Frederiksen-2
In reply to this post by Geopilot
I think it can be done like many small batteries can be made as one. but
I think it is ultimately much simpler to make one

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Re: Using many small electric motors.

damon henry
In reply to this post by Geopilot

> I want a three wheeler on the road I can build in the backyard. This for
> me is the only realistic way to do it for a number of reasons too
> numerous to go into.
>
Wow, talk about doing things the hard way.  Think about all the things you are trying to figure out to get this done.  All you need to get a small three wheeler going 30 mph is one of the easy to purchase and install e-bike hub motor kits.  Get one of the higher powered ones and over volt it a bit.  Trying to get 50 toy motors to work together sounds like a nightmare.  You are likely to end up spending just as much money, way more time, and end up with something much less reliable going this route.  I think in the end you would find that your list of pro's would be far out weighed by the cons.  

The interesting thing about motors and batteries is that you can tell a lot by weight.  The amount of power you can get out of a motor in general is comparable to the weight of copper that the electricity is going through and the amount of power you can get out of batteries is generally proportional to the weight when you are dealing with the same chemistry.

So if you are looking to replace a 60 lb ADC 6.7 inch motor with a bunch of toy motors you will need roughly 60 lbs worth of the toy motors, and if you are replacing 400 lbs worht of 12 volt deep cycle batteries you will need about 400 lbs worth of smaller lead acid batteries.  This is a very loose rule of thumb, but should help you ball park what you are proposing.

damon


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Re: Using many small electric motors.

FRED JEANETTE MERTENS
In reply to this post by Geopilot
Well  this is CERTAINLY THINKING OUT OF THE BOX  !!!  we have Cushman scooters at work the 3 wheel  type that you stand behind to drive and have a flatbed of 2'x 4' for cargo . they use a small controller and operate on 24vdc . you could use those controllers and maybe surplus aircraft motor/generator from the old piston engines or early jets these are relatively cheap . the Cushman at work are belt driven but you could make a large motor mount around a fly wheel  it would work and it would not take a huge group to make it go good and still be upgradeable with relatively cheap front end cost . and the controller for these are mechanical / electrical .

I think Roland has a business that deals with golf carts  they would have the same or like components  that you may be able to buy cheaply wholesale  or used !!! ask him he may be able to steer you to used golf cart places or to wholesale places  if you buy as a business ???
  ----- Original Message -----
  From: GWMobile<mailto:[hidden email]>
  To: Electric Vehicle Discussion List<mailto:[hidden email]>
  Cc: [hidden email]<mailto:[hidden email]>
  Sent: Saturday, December 22, 2007 9:07 AM
  Subject: [EVDL] Using many small electric motors.


  Has anyone taken the approach of using many small electric motors to
  build an electric vehicle?

  By MANY I mean MANY.

  Not 2 or three.

  Like say 10 to 50 per wheel.

  For example I have thought one way to start an electric vehicle project
  at low cost would be start a three wheeller with strong frame but little
  external covering (like the wrightspeed) and build a single gear
  flywheel or geared power wheelwith multiple attachments points around
  the perimeter gear for multiple motors so they could be added as
  afforded or scavenged.


  Several reasons/advantages of this design philosophy are.

  1.Cheaper to build in stages. You can have a rolling working vehicle
  with one or ten smaller motors andthen upgrade performance as you add
  motors.
  2. Individually wired small moters with separate batteries means
  batteries can be charged separatley using lower amp equipment and small
  wires.
  3. More reliability - if one motor and or its battery burns out you have
  49 more.
  4. You can control all the motors with one control circuit and still
  have amps for all circuits be low.
  5. All parts can be lower cost and purchased for normal mass production
  sources for electronics (although there are more of them) because each
  part takes lesss amps.
  6. as you ad motors you can add more shell weight to enclose vehicle
  (because you built the frame strong to handle future expansion.)
  7. You can run a few motors at high rpms if you want to change power or
  efficiency and then if you need more power use all the motors - on the
  fly!
  8. Cooling many small motors might be easier than one large one.
  9. Most small dc motors are also generators so braking recapture is
  easy.

  10. I might be able to recharge all batteries at once by designing a
  system to spin the power wheel on a jack with the drive motors all
  connected thus recharging all individual motor battery circuits at home
  without having to explicitly design a sequenced charger for each motor
  battery circuit.

  Now I realize there are many drawbacks so no one need to point them out
  endlessly and make THAT the primary subject of this thread. That's not
  the reason I am doing this. Incrementable building cost is the KEY issue
  for me as I want SOME kind of electic vehicle that will run - even if
  poorly- from day one until I can add capacity.

  ONE question I am trying to work out is how many toy motors would it
  take to allow a framed trike to run at 30 mph on level flat surface
  streets.
  Who can chime in one that?

  I want a three wheeler on the road I can build in the backyard. This for
  me is the only realistic way to do it for a number of reasons too
  numerous to go into.

  I just wondered if anyone has tried this approach.

  It is basically what the new tesla did with batteries for their supercar
  (hundreds of tiny mass market batteries) except I want to do it with
  batteries AND motors.

  Also I have been trying to compute the power to weight ratio and
  efficiency of say 100 toy electric motors compared to one big car
  electric motor.

  Anyone want to help firgure it out?

  I am thinking 10 to 50 toy electric motors per power wheel depending on
  which motors turn out to be best cost/power/weight/efficiency ratio.
  Eventually all three wheels could be power wheels allowing all kinds of
  special control of course but initially just one.

  The goal is to get it rolling not perfection! Don't waste time telling
  me how it won't be perfect!

  PLEASE waste time with calculations of how many motors it might take or
  any websites you find that have motors that might useful.

  My goal would be cheapest incremental cost at first and not performance
  but of course that could change as I build it adding higher performance
  motors later. That is the whole beauty of the design philosophy. I can
  add groups of motors and batteries for increased performance literally
  $20 at a time.

  The thing is while even surplus big ev motors rarely sell for super
  cheap prices there are OFTEN huge over runs on mass market toy electric
  motors with incredible discounts -sometimes boxes of hundreds of motors
  for $20 bucks etc. We are talking pennies a motor sometimes.

  And while I neverdue to lack of experince build a huge amp system - I
  have NO problem wiring 50 small motors with one rechargable battery each
  and one cheap variable control each and one mini plug each for
  recharging and mechanically linking all 50 variable controls to one
  handle so I can control all motors at once. And there is no
  electrocution dangers.

  Or controlling each with a transisitor and wiring all the transistors
  together. I could even control them with a light system with a whole
  bunch of ir tuned receivers leds on each motor circuit all responding
  from the vairable output of one ir led all enclosed in a
  box.(possibilites are endless)

  I have been trying to get reliable small motor power info on the cheaper
  toy motors but it is hard to find. Anyone who finds that info please
  post!

  Some of the more expensive electric rc airplane and car motors have
  incredible power to weight ratios but they tend to be more expensive.

  I just want a good price and power numbers for analysis.

  Thoughts and

  SPECIFIC NUMBERS for analysis wanted.

  Www.Ikickgas.com<http://www.ikickgas.com/>


  www.GlobalBoiling.com<http://www.globalboiling.com/> for daily images about hurricanes, globalwarming
  and the melting poles.

  www.ElectricQuakes.com<http://www.electricquakes.com/> daily solar and earthquake images.

  _______________________________________________
  For subscription options, see
  http://lists.sjsu.edu/mailman/listinfo/ev<http://lists.sjsu.edu/mailman/listinfo/ev>
_______________________________________________
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Re: Using many small electric motors.

FRED JEANETTE MERTENS
In reply to this post by Geopilot
the idea of 3 wheel motors from e bike is great  then if you want more power you could go for bob's idea or a motor for each wheel but use golf cart motors they are built fot that use have 1 mechinical control linkage and 3 small controllers ??
  ----- Original Message -----
  From: GWMobile<mailto:[hidden email]>
  To: Electric Vehicle Discussion List<mailto:[hidden email]>
  Cc: [hidden email]<mailto:[hidden email]>
  Sent: Saturday, December 22, 2007 9:07 AM
  Subject: [EVDL] Using many small electric motors.


  Has anyone taken the approach of using many small electric motors to
  build an electric vehicle?

  By MANY I mean MANY.

  Not 2 or three.

  Like say 10 to 50 per wheel.

  For example I have thought one way to start an electric vehicle project
  at low cost would be start a three wheeller with strong frame but little
  external covering (like the wrightspeed) and build a single gear
  flywheel or geared power wheelwith multiple attachments points around
  the perimeter gear for multiple motors so they could be added as
  afforded or scavenged.


  Several reasons/advantages of this design philosophy are.

  1.Cheaper to build in stages. You can have a rolling working vehicle
  with one or ten smaller motors andthen upgrade performance as you add
  motors.
  2. Individually wired small moters with separate batteries means
  batteries can be charged separatley using lower amp equipment and small
  wires.
  3. More reliability - if one motor and or its battery burns out you have
  49 more.
  4. You can control all the motors with one control circuit and still
  have amps for all circuits be low.
  5. All parts can be lower cost and purchased for normal mass production
  sources for electronics (although there are more of them) because each
  part takes lesss amps.
  6. as you ad motors you can add more shell weight to enclose vehicle
  (because you built the frame strong to handle future expansion.)
  7. You can run a few motors at high rpms if you want to change power or
  efficiency and then if you need more power use all the motors - on the
  fly!
  8. Cooling many small motors might be easier than one large one.
  9. Most small dc motors are also generators so braking recapture is
  easy.

  10. I might be able to recharge all batteries at once by designing a
  system to spin the power wheel on a jack with the drive motors all
  connected thus recharging all individual motor battery circuits at home
  without having to explicitly design a sequenced charger for each motor
  battery circuit.

  Now I realize there are many drawbacks so no one need to point them out
  endlessly and make THAT the primary subject of this thread. That's not
  the reason I am doing this. Incrementable building cost is the KEY issue
  for me as I want SOME kind of electic vehicle that will run - even if
  poorly- from day one until I can add capacity.

  ONE question I am trying to work out is how many toy motors would it
  take to allow a framed trike to run at 30 mph on level flat surface
  streets.
  Who can chime in one that?

  I want a three wheeler on the road I can build in the backyard. This for
  me is the only realistic way to do it for a number of reasons too
  numerous to go into.

  I just wondered if anyone has tried this approach.

  It is basically what the new tesla did with batteries for their supercar
  (hundreds of tiny mass market batteries) except I want to do it with
  batteries AND motors.

  Also I have been trying to compute the power to weight ratio and
  efficiency of say 100 toy electric motors compared to one big car
  electric motor.

  Anyone want to help firgure it out?

  I am thinking 10 to 50 toy electric motors per power wheel depending on
  which motors turn out to be best cost/power/weight/efficiency ratio.
  Eventually all three wheels could be power wheels allowing all kinds of
  special control of course but initially just one.

  The goal is to get it rolling not perfection! Don't waste time telling
  me how it won't be perfect!

  PLEASE waste time with calculations of how many motors it might take or
  any websites you find that have motors that might useful.

  My goal would be cheapest incremental cost at first and not performance
  but of course that could change as I build it adding higher performance
  motors later. That is the whole beauty of the design philosophy. I can
  add groups of motors and batteries for increased performance literally
  $20 at a time.

  The thing is while even surplus big ev motors rarely sell for super
  cheap prices there are OFTEN huge over runs on mass market toy electric
  motors with incredible discounts -sometimes boxes of hundreds of motors
  for $20 bucks etc. We are talking pennies a motor sometimes.

  And while I neverdue to lack of experince build a huge amp system - I
  have NO problem wiring 50 small motors with one rechargable battery each
  and one cheap variable control each and one mini plug each for
  recharging and mechanically linking all 50 variable controls to one
  handle so I can control all motors at once. And there is no
  electrocution dangers.

  Or controlling each with a transisitor and wiring all the transistors
  together. I could even control them with a light system with a whole
  bunch of ir tuned receivers leds on each motor circuit all responding
  from the vairable output of one ir led all enclosed in a
  box.(possibilites are endless)

  I have been trying to get reliable small motor power info on the cheaper
  toy motors but it is hard to find. Anyone who finds that info please
  post!

  Some of the more expensive electric rc airplane and car motors have
  incredible power to weight ratios but they tend to be more expensive.

  I just want a good price and power numbers for analysis.

  Thoughts and

  SPECIFIC NUMBERS for analysis wanted.

  Www.Ikickgas.com<http://www.ikickgas.com/>


  www.GlobalBoiling.com<http://www.globalboiling.com/> for daily images about hurricanes, globalwarming
  and the melting poles.

  www.ElectricQuakes.com<http://www.electricquakes.com/> daily solar and earthquake images.

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Re: Using many small electric motors.

Geopilot
In reply to this post by Geopilot
Thanks for the replies guys.

>> SPECIFIC NUMBERS for analysis wanted.
>    OK ya got them above.

Where ?
I am trying to get a decent idea of how many little motors and or small
batteries it would take to push along a trike at 30mph on level roads.
Did I miss the analysis?

>> SPECIFIC NUMBERS for analysis wanted.
>
>    OK ya got them above.
>
>    Seeya
>
>     Bob
>>

www.GlobalBoiling.com for daily images about hurricanes, globalwarming
and the melting poles.

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Re: Using many small electric motors.

Jeff Shanab
In reply to this post by Geopilot
I think it is like making an omelet for two from quails eggs. The total
weight of these motors in relation to their output is high. The
overhead, shaft,bearings,case is a higher percentage of the motor as it
gets smaller.


But you could take an aggregate approach on the calculations. I could
look it up but lets say you need  2hp to go 30mph with the weight
vehicle you have planned.

1 hp  =  746 watts so  1492 watts  assuming 80% eff motors  yields 1865
Watts
Assuming 12 volt toy motors that is 155Amps 10 motors at 15 A 12V?
pretty big!

what about electric scooter motors 36V? only 52Amps and they can handle
5A each so 10 of those might do the trick.

Maybe the best idea is just to go here http://www.surpluscenter.com/

and pick something like this

http://www.surpluscenter.com/item.asp?UID=2007122211500874&catname=electric&item=10-2355

or a high voltage low amp A123 pack might go with something like this

http://www.surpluscenter.com/item.asp?UID=2007122211500874&item=10-1751&catname=electric



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Re: Using many small electric motors.

EVDL Administrator
In reply to this post by FRED JEANETTE MERTENS
Just like an overgrown slot car - powered by Mabuchi! ;-)

I might look at using a handful of medium-sized motors rather than a
trunkful of tiny ones.  What large appliances use universal (series) motors?
 You want something that's typically discarded because something besides the
motor fails; that way you can scrounge at the landfill.

If you want a lower voltage drive, how about radiator fan motors from the
junkyard?  At least one E-bike used a Ford fan motor.

David Roden - Akron, Ohio, USA
EVDL Administrator

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Re: Using many small electric motors.

Lee Hart
In reply to this post by Geopilot
GWMobile wrote:
> Has anyone taken the approach of using many small electric motors to
> build an electric vehicle?
>
> By MANY I mean MANY.
>
> Not 2 or three.
>
> Like say 10 to 50 per wheel.

Interesting approach. I suppose it all depends on exactly what kind of
small motors you used.

All things being equal; the bigger a motor, the cheaper it is per
horsepower, and the higher its efficiency. But all things rarely are
equal; there are so many differences in the specifics that this is hard
to apply -- a well-made small motor can beat a badly-made big one.

Most small motors are really cheaply and badly built. Low efficiency,
bad bearings, poor cooling -- they are built for things like toys or
gadgets that have a total life expectancy of only a matter of hours.
Such motors would be of no practical use.

But, there are some pretty good small motors. Some of the ones used by
R/C modellers have amazing power-to-weight ratios. There are some
precision servo motors with very high efficiency and reliability. If you
found a "deal" on a case of small high quality motors, your scheme might
work.

I corresponded with a fellow that was using six golf cart motors to
drive his pickup truck. He did it because he happened to have a pile of
golf cart parts surplus.

He made an adapter plate with six holes around the center to mount the
motors. Each motor had an identical gear. A large mating central gear
went on the transmission shaft. The six motor's bearings served to
position the central gear (since the transmission didn't have a front
bearing).

Last I heard, it did work. No comparative performance data, as it was
his first EV and just for "fooling around".

--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in    --    Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net

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Re: Using many small electric motors.

Peter VanDerWal
In reply to this post by Geopilot
It's hard to make an analysis without details to base it on.

As a swag, a small trike that is reasonably aerodynamic and light weight
can hit 30 mph with about 750 watts (motor output) so you need enough
whatever motors to equal about 700-800 watts.

You will need at least one battery.  How many more yo need depends on how
much power the batteries can produce and how long (far) you want to go.

> Thanks for the replies guys.
>
>>> SPECIFIC NUMBERS for analysis wanted.
>>    OK ya got them above.
>
> Where ?
> I am trying to get a decent idea of how many little motors and or small
> batteries it would take to push along a trike at 30mph on level roads.
> Did I miss the analysis?
>
>>> SPECIFIC NUMBERS for analysis wanted.
>>
>>    OK ya got them above.
>>
>>    Seeya
>>
>>     Bob
>>>
>
> www.GlobalBoiling.com for daily images about hurricanes, globalwarming
> and the melting poles.
>
> www.ElectricQuakes.com daily solar and earthquake images.
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>


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Re: Using many small electric motors.

Arak Leatham
In reply to this post by Geopilot

I haven't looked at the rest of the answers here so forgive me if I dupliacte any.
 
I think the micro motors are going cost you too much in drive gears and other hardware etc.
 
You may consider using hand tool motors. You can get some at your local 'Habor Freight' store or other secondary outlet. At thrift shops you can find them lacking the batteries etc.



 




Arak Leatham - Web and Desktop Systems Developer> Date: Sat, 22 Dec 2007 10:07:55 -0500> To: [hidden email]> From: [hidden email]> CC: [hidden email]> Subject: [EVDL] Using many small electric motors.> > Has anyone taken the approach of using many small electric motors to > build an electric vehicle?> > By MANY I mean MANY.> > Not 2 or three.> > Like say 10 to 50 per wheel.> > For example I have thought one way to start an electric vehicle project > at low cost would be start a three wheeller with strong frame but little > external covering (like the wrightspeed) and build a single gear > flywheel or geared power wheelwith multiple attachments points around > the perimeter gear for multiple motors so they could be added as > afforded or scavenged.> > > Several reasons/advantages of this design philosophy are.> > 1.Cheaper to build in stages. You can have a rolling working vehicle > with one or ten smaller motors andthen upgrade performance as you add !
 > motors.> 2. Individually wired small moters with separate batteries means > batteries can be charged separatley using lower amp equipment and small > wires.> 3. More reliability - if one motor and or its battery burns out you have > 49 more.> 4. You can control all the motors with one control circuit and still > have amps for all circuits be low.> 5. All parts can be lower cost and purchased for normal mass production > sources for electronics (although there are more of them) because each > part takes lesss amps.> 6. as you ad motors you can add more shell weight to enclose vehicle > (because you built the frame strong to handle future expansion.)> 7. You can run a few motors at high rpms if you want to change power or > efficiency and then if you need more power use all the motors - on the > fly!> 8. Cooling many small motors might be easier than one large one.> 9. Most small dc motors are also generators so braking recapture is > easy.> > 10. I might be able to recharg!
 e all batteries at once by designing a > system to spin the po!
 wer whee
l on a jack with the drive motors all > connected thus recharging all individual motor battery circuits at home > without having to explicitly design a sequenced charger for each motor > battery circuit.> > Now I realize there are many drawbacks so no one need to point them out > endlessly and make THAT the primary subject of this thread. That's not > the reason I am doing this. Incrementable building cost is the KEY issue > for me as I want SOME kind of electic vehicle that will run - even if > poorly- from day one until I can add capacity.> > ONE question I am trying to work out is how many toy motors would it > take to allow a framed trike to run at 30 mph on level flat surface > streets.> Who can chime in one that?> > I want a three wheeler on the road I can build in the backyard. This for > me is the only realistic way to do it for a number of reasons too > numerous to go into.> > I just wondered if anyone has tried this approach.> > It is basically what the new tesla d!
 id with batteries for their supercar > (hundreds of tiny mass market batteries) except I want to do it with > batteries AND motors.> > Also I have been trying to compute the power to weight ratio and > efficiency of say 100 toy electric motors compared to one big car > electric motor.> > Anyone want to help firgure it out?> > I am thinking 10 to 50 toy electric motors per power wheel depending on > which motors turn out to be best cost/power/weight/efficiency ratio. > Eventually all three wheels could be power wheels allowing all kinds of > special control of course but initially just one.> > The goal is to get it rolling not perfection! Don't waste time telling > me how it won't be perfect!> > PLEASE waste time with calculations of how many motors it might take or > any websites you find that have motors that might useful.> > My goal would be cheapest incremental cost at first and not performance > but of course that could change as I build it adding higher performance > m!
 otors later. That is the whole beauty of the design philosophy!
 . I can
> add groups of motors and batteries for increased performance literally > $20 at a time.> > The thing is while even surplus big ev motors rarely sell for super > cheap prices there are OFTEN huge over runs on mass market toy electric > motors with incredible discounts -sometimes boxes of hundreds of motors > for $20 bucks etc. We are talking pennies a motor sometimes.> > And while I neverdue to lack of experince build a huge amp system - I > have NO problem wiring 50 small motors with one rechargable battery each > and one cheap variable control each and one mini plug each for > recharging and mechanically linking all 50 variable controls to one > handle so I can control all motors at once. And there is no > electrocution dangers.> > Or controlling each with a transisitor and wiring all the transistors > together. I could even control them with a light system with a whole > bunch of ir tuned receivers leds on each motor circuit all responding > from the vairable output of o!
 ne ir led all enclosed in a > box.(possibilites are endless)> > I have been trying to get reliable small motor power info on the cheaper > toy motors but it is hard to find. Anyone who finds that info please > post!> > Some of the more expensive electric rc airplane and car motors have > incredible power to weight ratios but they tend to be more expensive.> > I just want a good price and power numbers for analysis.> > Thoughts and> > SPECIFIC NUMBERS for analysis wanted.> > Www.Ikickgas.com> > > www.GlobalBoiling.com for daily images about hurricanes, globalwarming > and the melting poles.> > www.ElectricQuakes.com daily solar and earthquake images.> > _______________________________________________> For subscription options, see> http://lists.sjsu.edu/mailman/listinfo/ev
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Re: Using many small electric motors.

Arak Leatham
In reply to this post by Geopilot

You have not made enough chioces to make an analysis. How heavy will your vehicle be? How strong? what load capacity? You need a design before you know all that.
 
You also need to pick out a motor that you can that many of, and figure out the torque and power output. You also must check the weight. We don't know what you have a vailable to you, that you would want.
 
The little ones are less efficient than larger motors, so it is just possible to not get what you want from that size of motor. To make up for it you would need to get high efficiency motors, and these will cost you more than the same power from a larger motor. For the price of 500, $3 motors, you can get a very nice $1500 motor.
 
It is better to save your money up and buy your pieces when you can, rather than dedicate your project to buying something each and every paycheck.
 
Personally, I have the same problem. I am now trying to design the cheepest design for my choice of specs that I can. I'm also limited by the tools I have, can afford and have the room for. It is much cheeper than my Taddy at www.detalidon.com
 
When I get it done, I'll post it in images and add it to my website. errr, When I get the silly website done, the new pages I mean.



 




Arak Leatham - Web and Desktop Systems Developer> Date: Sat, 22 Dec 2007 12:43:38 -0500> To: [hidden email]> From: [hidden email]> CC: [hidden email]> Subject: Re: [EVDL] Using many small electric motors.> > Thanks for the replies guys.> > >> SPECIFIC NUMBERS for analysis wanted.> > OK ya got them above.> > Where ?> I am trying to get a decent idea of how many little motors and or small > batteries it would take to push along a trike at 30mph on level roads.> Did I miss the analysis?> > >> SPECIFIC NUMBERS for analysis wanted.> >> > OK ya got them above.> >> > Seeya> >> > Bob> >>> > www.GlobalBoiling.com for daily images about hurricanes, globalwarming > and the melting poles.> > www.ElectricQuakes.com daily solar and earthquake images.> > _______________________________________________> For subscription options, see> http://lists.sjsu.edu/mailman/listinfo/ev
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Re: Using many small electric motors.

Geopilot
In reply to this post by Jeff Shanab
Thanks for the analysis. That kind of thing is really helpful.
If 2 hp is a good number for 30 mph on level that gives me a good
start.

By the way does anyone know how to measure hp?
It is the power to lift a certain weight a certain height in a certain
amount of time right?

I want to directly measure the hp of some small motors by having them
raise some weight with a string.


On Sat, 22 Dec 2007 12:58 pm, Jeff Shanab wrote:

> I think it is like making an omelet for two from quails eggs. The total
> weight of these motors in relation to their output is high. The
> overhead, shaft,bearings,case is a higher percentage of the motor as it
> gets smaller.
>
>
> But you could take an aggregate approach on the calculations. I could
> look it up but lets say you need  2hp to go 30mph with the weight
> vehicle you have planned.
>
> 1 hp  =  746 watts so  1492 watts  assuming 80% eff motors  yields 1865
> Watts
> Assuming 12 volt toy motors that is 155Amps 10 motors at 15 A 12V?
> pretty big!
>
> what about electric scooter motors 36V? only 52Amps and they can handle
> 5A each so 10 of those might do the trick.
>
> Maybe the best idea is just to go here http://www.surpluscenter.com/
>
> and pick something like this
>
> http://www.surpluscenter.com/item.asp?UID=2007122211500874&catname=electric&item=10-2355
>
> or a high voltage low amp A123 pack might go with something like this
>
> http://www.surpluscenter.com/item.asp?UID=2007122211500874&item=10-1751&catname=electric
>
>
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev

www.GlobalBoiling.com for daily images about hurricanes, globalwarming
and the melting poles.

www.ElectricQuakes.com daily solar and earthquake images.

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Re: Using many small electric motors.

Geopilot
In reply to this post by EVDL Administrator
Radiator fan motors might be a great idea.
Dc and mass produced. Bigger than a toy motor and probably built with
lightweight componenets.
Thanks for that.

Probably some factory on alibaba.com that is offering new ones by the
boatload for cheap if they are used in car parts.

On Sat, 22 Dec 2007 1:22 pm, EVDL Administrator wrote:


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Re: Using many small electric motors.

Geopilot
In reply to this post by Lee Hart
That's the kind of thing I was wondering.
Glad to see someone has done it.


I actually think some of the toys motors would last long time as long as
no motor took more of its share of load and all were properly aligned.

I don't know about you but I put my electric toys through hell and those
things keep going.
:-)

I wonder how much power say one hundred toy slot car motors or 99. Cents
store toy car motors would put out if arranged around the inside hub of
one wheel.

I have not been able to find any performance specifics on toy motors
from china etc on alibaba.com except for basic size and volts etc but no
total power.


On Sat, 22 Dec 2007 1:23 pm, Lee Hart wrote:

> GWMobile wrote:
>>  Has anyone taken the approach of using many small electric motors to
>>  build an electric vehicle?
>>
>>  By MANY I mean MANY.
>>
>>  Not 2 or three.
>>
>>  Like say 10 to 50 per wheel.
>
> Interesting approach. I suppose it all depends on exactly what kind of
> small motors you used.
>
> All things being equal; the bigger a motor, the cheaper it is per
> horsepower, and the higher its efficiency. But all things rarely are
> equal; there are so many differences in the specifics that this is hard
> to apply -- a well-made small motor can beat a badly-made big one.
>
> Most small motors are really cheaply and badly built. Low efficiency,
> bad bearings, poor cooling -- they are built for things like toys or
> gadgets that have a total life expectancy of only a matter of hours.
> Such motors would be of no practical use.
>
> But, there are some pretty good small motors. Some of the ones used by
> R/C modellers have amazing power-to-weight ratios. There are some
> precision servo motors with very high efficiency and reliability. If
> you
> found a "deal" on a case of small high quality motors, your scheme
> might
> work.
>
> I corresponded with a fellow that was using six golf cart motors to
> drive his pickup truck. He did it because he happened to have a pile of
> golf cart parts surplus.
>
> He made an adapter plate with six holes around the center to mount the
> motors. Each motor had an identical gear. A large mating central gear
> went on the transmission shaft. The six motor's bearings served to
> position the central gear (since the transmission didn't have a front
> bearing).
>
> Last I heard, it did work. No comparative performance data, as it was
> his first EV and just for "fooling around".
>
> --
> Ring the bells that still can ring
> Forget the perfect offering
> There is a crack in everything
> That's how the light gets in    --    Leonard Cohen
> --
> Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net
>
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev

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Re: Using many small electric motors.

Geopilot
In reply to this post by Lee Hart

I wonder theoritically shouldn't a bunch of small motors who have more
of their magnets closer to the field of their windings on average have
higher efficiency than larger motors which have more of their windings
further way from the magnets because of their larger size?

I mean a small motor is encapsulated totally within .25 inch of its
winding and magnet field.

A large motor might have parts of windings that are several inches away
from the magnets.

Isn't that logical?

> All things being equal; the bigger a motor, the cheaper it is per
> horsepower, and the higher its efficiency. But all things rarely are
> equal; there are so many differences in the specifics that this is hard
> to apply -- a well-made small motor can beat a badly-made big one.
>
>
> But, there are some pretty good small motors. Some of the ones used by
> R/C modellers have amazing power-to-weight ratios.

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Re: Using many small electric motors.

Geopilot
In reply to this post by Jeff Shanab
You know I am not so sure its true that weight of the small motors is
higher because thickness of casing walls etc must expand exponenetially
as size goes up. Small motors casings can be made of shaped tin.
Now small motor friction issues might be more but I don't know.

On Sat, 22 Dec 2007 12:58 pm, Jeff Shanab wrote:

> I think it is like making an omelet for two from quails eggs. The total
> weight of these motors in relation to their output is high. The
> overhead, shaft,bearings,case is a higher percentage of the motor as it
> gets smaller.
>
>
> But you could take an aggregate approach on the calculations. I could
> look it up but lets say you need  2hp to go 30mph with the weight
> vehicle you have planned.
>
> 1 hp  =  746 watts so  1492 watts  assuming 80% eff motors  yields 1865
> Watts
> Assuming 12 volt toy motors that is 155Amps 10 motors at 15 A 12V?
> pretty big!
>
> what about electric scooter motors 36V? only 52Amps and they can handle
> 5A each so 10 of those might do the trick.
>
> Maybe the best idea is just to go here http://www.surpluscenter.com/
>
> and pick something like this
>
> http://www.surpluscenter.com/item.asp?UID=2007122211500874&catname=electric&item=10-2355
>
> or a high voltage low amp A123 pack might go with something like this
>
> http://www.surpluscenter.com/item.asp?UID=2007122211500874&item=10-1751&catname=electric
>
>
>
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Re: Using many small electric motors.

Geopilot
In reply to this post by damon henry
Well the START  is for 30mph.
So I want to plan on adding more of the same system as I go up in
speed.

>  All you need to get a small three wheeler going 30 mph is one of the
> easy to purchase and install e-bike hub motor kits.

Ugh about below power equals weight of mower conclusion below.

If that is true then the only benefit of small motors might be they cost
less per pound if indeed they do.

But at least that's easy to calculate based on shipping weight!

>   The amount of power you can get out of a motor in general is
> comparable to the weight of copper that the electricity is going
> through and the amount of power you can get out of batteries is
> generally proportional to the weight when you are dealing with the same
> chemistry.
>
>

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