disecting a Sanyo/Rabbit Tool 250W PAS geared hub motor

rkosiorek

100 kW
Joined
Jan 18, 2007
Messages
1,770
Location
Belleville, Ontario Canada
this motor is a PAS only 250W hubmotor with everything built into the hub except for the batteries. built into the hub are the motor, controller and torque sensor. two wires connect to the outside world one pair goes to the 24V battery pack and a small gauge set of wires go to a handle bar mounted ON/OFF switch.

this motor was removed from a Mikkado Volta bike. the owner was tired of the PAS and wanted to convert it to a POD throttle operated motor.

so the first thing i needed to do is gut the motor and take some pictures.

spokes on this thing were really beefy 12Gage spokes like those used on Sulky wheels used in harness racing
 

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Now we get to the guts. the 3 drive belts together give a total reduction of 21.5 to 1.

each belt has its own tension adjustment.

there is a roller clutch that will disconnect the wheel from the motor and allow it to freewheel.

note fully embeded controller with attached speed sensor and torque sensor. more on how these work later.
 

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a few more pictures of the mechainical details of the 3 stage belt drive reduction system.

works pretty good but it is noisy. those toothed bets whine quite a bit.
 

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this is the fully potted controller that is being discarded from the motor.
 

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how the torque sensor works

- the freewheel mounts to a steel adapter
- the steel adapter has a couple of bearings and it can turn on the axle.
- the drum mounts to the final drive pulley
- the final drive pulley has a couple of bearings and it can also spin on the rear axle
- the steel adapter has 4 lugs that fit through 4 holes in the pulley
- 2 of these lugs press against spring loaded pistons mounted inside the pulley that hold the adapter in position
- when you push on the pedals the tension on the freewheel forces the adapter to change its position inside the pulley. the change is resisted by the piston/spring.
- the other 2 adapter lugs have ramps thact act as cams to move a metal ring in an outfrom the pulley
- the harder you push on the pedals - the more the adapter turns and the further out the metal ring moves from the pulley.
- the metal ring moves in/out the torque sensor pickup. this changes the inductor value of the pickup

neat huh.

the speed sensor is triggered by a magnet that is mounted to the bottom of the final drive pulley. it works just like a regular bike spedometer.

so it works like this:

1. power on - when you pedal it measures your torque input and uses that to control the electric motor to catch up.

2. power off - the freewheel adapter is only allowed to move a few degress before it locks up on the pulley and turns the wheel directly.
 
no you don't need to unspoke the wheel. i did that because the guy it was going to was going to re-lace it to a 24" rim.

now he changed his mind and is going to get a crystalyte brushed 409 instead.

EVSolutions had a pair of these bikes and now that the motor has been converted to use an external Crystalyte controler he wants to re-mount one of them to the orignal frame.

i want to take the other one and cut a couple of holes in the LHS cover so i can use a pair of EV Warrior motors with the belt reduction. want to put it back on a EV Warrior frameset i have kicking around. get rid of the friction drive, 36V 13Ah NiMh Batteries and it should fly.

rick
 
rember that was 1000W at 24V. and the old friction drive roller vs wheel diameter was also 20:1 reduction. even with a bit of slip this was an impressive amount of pulling power.

now at 36V and no slip in the drive i smell an unhealthy grin factor coming into play.

i'm going to use a crystalyte brushed 36V controller with upgraded IRFB4110 fets. Bob Mcree thinks 120A+ is possible.

it will either work "real good" or i'm going to strip the teeth off of the first belt.

rick
 
i'm ony worried about the first small belt that attaches to the motor shaft. the other 2 are more than adequated for a couple of horsepower.

the 1st small belt will be replaced by a wider one that should be adequate.

rick
 
rkosiorek said:
i'm ony worried about the first small belt that attaches to the motor shaft. the other 2 are more than adequated for a couple of horsepower.

the 1st small belt will be replaced by a wider one that should be adequate.

rick

Rick,

They're probably ok in proportion to the torque in their respective parts of the drive...
 
Hi Rick

Nice sharp photos and good explanation, it looks a little complicated in there doesnt it! those pesky torque sensors! spoiling all the fun. Are you thinking of driving that motor with a beefed up controller though? it looks way to small IMHO its hard to get a good idea of scale but id worry about more than 600W going through that little fella! there is no doubt the belts and pulleys should cope though.

Interesting little motor though, wonder when we are going to see the holy grail and someone make an internally multi speed geared brushless hub motor then!

Knoxie
 
Thanks for the wonderful pictures, love to see how all this stuff works. Must say this is one of the more thought out creations I've seen, those belts can handle more power than you give them credit for i think.
Great picture, thanks again.
 
knoxie said:
Hi Rick

Nice sharp photos and good explanation, it looks a little complicated in there doesnt it! those pesky torque sensors! spoiling all the fun. Are you thinking of driving that motor with a beefed up controller though? it looks way to small IMHO its hard to get a good idea of scale but id worry about more than 600W going through that little fella! there is no doubt the belts and pulleys should cope though.

Interesting little motor though, wonder when we are going to see the holy grail and someone make an internally multi speed geared brushless hub motor then!

Knoxie

nah knoxie you missed the point. i've got a couple of original EV Warrior/Bosch 450W motors. since the controller is gone i have plenty of realestate inside the case. i plan on removing the original motor and replacing it with the pair of EV Warrior motors. except now they won't have that pesky friction drive.

once it is mounted on the bike most of it will be hidden under the warrior battery box. it should look almost like a stock EV Warrior with mirrors turnsignals and everything else.

since the motors will not be inside the battery case anymore i should have enough room for a 36V pack in there. should be a real hoot.

rick
 
Does this hub motor fit in to any regular frame? Can one swap it back and forth just like normal wheel assembly? Is this it here:

mercedes_hybrid1.jpg
 
I thought I'd seen this hub motor somewhere before. The Mercedes hub motor appears identical to the Sanyo hub motor.

One wee correction to what Rick wrote, the hub motor came from a Mikado Elektron Cruiser Bike and not the older Mikado Volta Bike.

The e-bike Dealer who had these Mikado e-bikes had them priced at $1599.00 and didn't sell even one after 2 years. I got his 2 and set the price at $700.00 with the Ni-CD pack and still no one wanted to buy one. It was this whole Euro thing about the need to use the Pedals as something other than a place so your shoes don't drag on the pavement.

North Americans like Power on Demand and a Pedelec is an alien concept

The Motor itself was designed by Rabbittool and Licensed to Sanyo

Luckily I have 2 Mikado bikes because the 1st Mikado had its front fork dropouts destroyed by the torque of the Falcon 500W Hub Motor I got to ride 55 feet before doing an amazingly hard and fast Face Plant on the road---> am way too old to be laying on the road. My Helmet is toast but better it than my skull. Oh and if life could not be anymore fun the bike did an End Over and landed on my back and I had to be dragged out from under it.

Just to totally destroy your day with this mental image, in June when I took the Mikado for a demo ride and being a hot day I stopped for a Perrier at a cafe'. When I came out I saw someone stole the seat (saddle) from the bike. Being lazy and a skilled cyclist I decided to ride it home without a Seat. Being a Pedelec it meant standing on the pedals and pedaling all the time.
The Mental Image was while Pedaling my trousers & undies suddenly slipped down around my knees and I could not let go of the handlebars to pull them back up and I had a car behind me so I couldn't hit the brakes. Being in a Gay Area of Toronto no one seemed to notice except 2 males walking side by side and they did a Wolf Whistle and I yelled "I'm Straight" and one yelled back "Yes it is". I didn't want to think of what he meant.
 
yes the mercedes did use the Sanyo/Rabbit tool motor. there were only some slight cosmetic changes.

that mercedes is a cool looking bike.

yes it can be fitted to any frame with wide enough rear dropouts. ie. 135~145 mm. on the freewheel side the spacing can be adjusted using the 2 thin nuts on the axle. just remove the freewheel to see these nuts.

rick
 
Hi
Please can anybody tell me how i can de-restrict this motor i have on my mercedes hybrid bike and any other info you have on this bike.
thanks,
Wraggy :roll:
 
The internal controller is completetly potted and not accessable. there does not appear to be a programing port or any other way to access the software. so to answer the question there is no way that i know of to de-restrict this torque sensor/controller/motor combination.

the motor though is a pretty conventional brushed DC motor. if you ditch the torque sensor and controller you can add a conventional throttle and brushed motor controler. this is what i did with one of these. it is presently on a bike using 36V and a 20A controller. since i have not heard any complaints from the owner i guess it is working okay.

rick
 
Since the speed sensor is a magnet thing like on a bike computer, then extending the wires and mounting the pickup on the cranks would disable speed limiting.

Also looks like there's a shunt here, adding solder should let it pass more amps:

 
rkosiorek said:
The internal controller is completetly potted and not accessable. there does not appear to be a programing port or any other way to access the software. so to answer the question there is no way that i know of to de-restrict this torque sensor/controller/motor combination.

the motor though is a pretty conventional brushed DC motor. if you ditch the torque sensor and controller you can add a conventional throttle and brushed motor controler. this is what i did with one of these. it is presently on a bike using 36V and a 20A controller. since i have not heard any complaints from the owner i guess it is working okay.

rick
Hi Rick
Hope you got my address ok

Please you tell me the name of the man again who desinged the motor/hub again
thanks,
Wraggy
 
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