Big mobility scooter motor

[Fly_boy_bc]

I am building a chain driven motor assist chopper bike. (O.C.C Schwinn Stingray lookalike)

For power I have a motor and controller from an Invacare Panther MX-4. The fellow at the store told me it Was either 1.5 or 2 HP...Not in that range but one or the other.

I purchased two brand new 37 AH 12V. SLA batteries and I am about ready to begin fabrication.

I have several questions. All of them about the motor which really need to be answered before I can go much farther.

Firstly does anybody know what the no load RPM would be? Even if you just know about mobility scooters in general please answer so far that piece of data has eluded me.

Can I run this 24V motor at 36V. and get away with it?

Do I have to worry about the fact that the motor will be driven by the wheel whenever I try to coast? I have been planning to use a BMX freewheel rear sprocket as the drive sprocket so This would not happen but if I can avoid an unnecessary complication I will.

Motor: Pihsiang Machinery Mfg. Order code M3-9MNF-2A



Thanks!

 

[Jerryburger]

No clue on what the no-load rpm is.... it's not geared down, right? Most electric motors seem to do fine going "one step up" in voltage (12-24, 24-36, etc...). Is it vented? If it isn't, you might want to give that some consideration. 1.5 hp will make that bike fly.

 

[Fly_boy_bc]

No clue on what the no-load rpm is.... it's not geared down, right?

Nope no gearing

Most electric motors seem to do fine going "one step up" in voltage (12-24, 24-36, etc...). Is it vented? If it isn't, you might want to give that some consideration.

You think I should drill some vent holes?

1.5 hp will make that bike fly.

Yah that was the plan...I got big batteries so I could use this as a commuter. I got a big motor 'cause....'cause...well I LIKE big motors.:biggrin5:

Gary

 

[Jerryburger]

Drilling the vent holes?... Be VERY CAREFULL when you do it.

 

[ryf]

do not drill vent holes unless you can separate the housing from the motor, you don't want any filings or a drill bit getting into something expensive.. I probably wouldn't do it period, but thats me.

That said, if you can take the housing off, find something like a 2x4 or 4x4 (or bigger as needed) to fit inside and keep the housing from deflecting beyond repair while you are drilling holes in it.

 

[Fly_boy_bc]

Invacare Panther MX-4 mobility scooter motor.

Does anybody know what the no load RPM would be? Even if you just know about mobility scooters in general please answer so far that piece of data has eluded me.

 

[Fly_boy_bc]

do not drill vent holes unless you can separate the housing from the motor, you don't want any filings or a drill bit getting into something expensive.. I probably wouldn't do it period, but thats me.

That said, if you can take the housing off, find something like a 2x4 or 4x4 (or bigger as needed) to fit inside and keep the housing from deflecting beyond repair while you are drilling holes in it.

I would have no problem getting it apart and the casing is really solid.

Holy moly I just got the controllers service manual from Penny and Giles. This sucker is 110 Amps!

110 Amps times 24 Volts is 2640 Watts!! That's 3.54 Horses!

DC motors ARE rated by their continuous output so I must have the 2 HP version.

does anybody know what the no load RPM would be? Even if you just know about mobility scooters in general please answer so far that piece of data has eluded me.

Thanx GBGB

 

[Jerryburger]

Um, I'm going to take a shot-in-the-dark guestimate @ 3000-4000 rpm. I'm basing this on my old battery-operated reel-mower motor, rated at 2hp. When geared 5:1 on my stand-up 3 wheeler (10" wheels), it'd hit between 18-20mph or so.
With your schwinn bike, I'd shoot for about an 8:1 or 9:1 ratio.
Again, this is just a shot in the dark.
If one were to ABSOLUTELY want to know what it is, get a bike with a speedometer. Turn it upside down, fire up the motor and friction drive the wheel that the speedo is hooked up to. Then, knowing how much distance is being covered per minute, you just need to factor in the diameter of the motor shaft that you were friction driving with. It's not exact, but it'll put you in the ballpark.
Either way, you've got a very nice base to build an electric project from!

 

[kibble]

Flyboy, I hate to say this, but unless you can get the Mobility company from releasing that information, you're probably not going to be able to find out what the no load rpm is.

Well, I just did a quick search and found this:

http://www.medequipb2b.com/work/b_index.jsp?supplier=24512&industry=MH

Maybe you'll want to shoot them an email with questions about your motor. If you decide to do so, maybe you'll get a reply!

 

[Fly_boy_bc]

Thanks! Hi Ho...Hi Ho.....

Um, I'm going to take a shot-in-the-dark guestimate @ 3000-4000 rpm.

That's about what I figured

I'm basing this on my old battery-operated reel-mower motor, rated at 2hp. When geared 5:1 on my stand-up 3 wheeler (10" wheels), it'd hit between 18-20mph or so.
With your schwinn bike, I'd shoot for about an 8:1 or 9:1 ratio.

The Schwinn chopper lookalike I have has a 20" rear wheel. Does that change your ratio estimate at all?

Either way, you've got a very nice base to build an electric project from!

Thanks Jerry I agree! The Panthers gross weight was 400 Lbs. I believe my AUW will be a little under three hundred. I should be able to get 30 MPH and still be able to climb hills.

Tomorrow I will be building some panniers like these

http://rtw.xtz660.googlepages.com/alluboxes

They will hold the batteries the charger and the ESC.



GBGB

 

[Fly_boy_bc]

Flyboy, I hate to say this, but unless you can get the Mobility company from releasing that information, you're probably not going to be able to find out what the no load rpm is.

Well, I just did a quick search and found this:

http://www.medequipb2b.com/work/b_index.jsp?supplier=24512&industry=MH

Maybe you'll want to shoot them an email with questions about your motor. If you decide to do so, maybe you'll get a reply!

I have already e-mailed them at two different contact addresses. Nothing...I E-mailed Penny and Giles (the ESC manufacturer) and recieved TWO answers both of which came with the controllers technical manual! The only problem I see with using the controller is that it has a pre-programmed top speed and acceleration. Sucks but maybe I can reprogram it if it's too limiting Or just steal the MOSFETS or Traics or power transistors or whatever it uses and build a simpler version of the same ESC. No computer.

Any comments?

I have a few PICAXE chips...

http://www.theworkshop.ca/energy/picox/picox.htm

GBGB

 

[Jerryburger]

Funny you should mention the controllers.... That was one part of Bob's wheelchair motor project that was frustrating. The controller tries to outsmart you on the throttling. (I'm sure to avoid lawsuits by someone pulling a good wheelie on accident!) . It even would apply a sort of regenerative brake if you let off the throttle too quickly- almost put you over the handlebars. In the end, he got frustrated and bought one of those huge Ford-styled auto relays and made it an all-or-nothing setup.... which wasn't too bad because the motor wasn't too powerful and it was easy to manipulate the speed. He put 2 marine deep-cycle batteries in a butchered bike trailer and towed them from behind. If you were able to get a ho;d of, or build your own controller, you'd be way ahead. That motor should get you the speed you want easily. It's the range that's in question.

 

[kibble]

Yeah, a lot of those commercial motor controllers from are way too limited for anything cool. I want to make a motor controller out of an R/C servo controller board, the tiny board inside a servo. All I basically have to do is use a circuit similar to the one that I used on my kart and beef up the current handling on the motor end of the servo board. I'll post pics when I get around to it. No programming necessary, but I wouldn't get some of the cool features that the expensive controllers have.

 

[Fly_boy_bc]

I want to make a motor controller out of an R/C servo controller board, the tiny board inside a servo.

Why not start from a R/C D.C. ESC? (old school pre-brushless) instead of a servo board? I mean it already has some features you would want. Reverse etc.

Gary

 

[kibble]

Yeah, I could, but it's easier and cheaper to butcher a servo than an ESC. Besides, servos are already able to do forward and reverse. It just requires interfacing the regular motor outputs and boost them with some MOSFETS, and I got plenty of those.

 

[Jerryburger]

Ooooo! I know a couple of guys I'M going to pester for info when I try my next electric project!