Schwinn Electric Stingray 24V to 48V conversion

[sandsz]

Hello!

First off I'd like to thank all the contributors of this board for whom I ready many upon many pages of wonderful first hand experience which became useful in my build.

I bought a Schwinn Electric Stingray at my local Goodwill fo r$35. My wife said I will silly but from previous experience with motorcycle building and passing knowledge of electric bikes, I knew there was something special to be had. It had flat front and rear tires, tread poking out from the rim where ppl have ridden on flat tires before, the front forks were tweeked and tire was not center. In a word it looked rough... but not to me!.



So I bought it, took it apart, surprisingly re-seated both front and rear tires and found nothing and aired them up the proper way. Both perfectly round and fine now!
I took the whole front fork aparts, greesed the bearings and bent back the front hangers for the front tire.

I then bought 4 12V 12aH batteries (generic 12120 type).

I replaced the two included batteries and it run fine. From this fourm, I too noticed what looked like a third battery place located in the "motor" looking battery case. I wired one in and it run pretty good.

I then mapped out a way to install the 4th battery with still retaining the battery "motor" and attaching it to the same pack.

Lastly my wiring required a 24V / 48V switch. View attachment 1 Mostly for charging reasons, so again reading this fourm I came across a DPDT switch. Same day I picked up one from radio shack and wired in everything. I charge by plugging in my computer power cord / XLR female jack and plugging in a nice 24V 2A charger.

I used two GPS devised and came up with the following:
24V - flat 13mph.
48V - Flat 25.2mph
48V - Uphill 14mhp
48V - downhill 30mph

I also got two offers to pay for the bike already, haha.

Total build cost $135. Very VERY fun though!

 

[e-beach]

sandsz.....Very nicely done.....
Looks like you got a great deal and made it work. Big pats on the back for this build.

I do have one question though. Could you please give us a close up shot of the rear axles? I am curious about the torque arm setup....

Also,


Nice job.....

 

[sandsz]

Thank You. It looks much like a motorcycle's rear tire in that it uses adjusters and no real bicycle "drop outs" The front tire axle is also held on by small keepers that prevent it from dropping out either.

Rear End


Right Hand Side


Left Hand Side

 

[sandsz]

Hey I'm not sure what is going on but it seems the forum duplicated my thread! Could this be cleaned up and I guess this thread remain? Thanks!

 

[Goathead]

You might show your wife this:
http://www.ebay.com/itm/Electric-Schwinn-Sting-Ray-Chopper-Bike/321219757743?_trksid=p2047675.m1985&_trkparms=aid%3D444000%26algo%3DSOI.CURRENT%26ao%3D1%26asc%3D17906%26meid%3D1663377923080829115%26pid%3D100012%26prg%3D8262%26rk%3D3%26rkt%3D5%26sd%3D321217799852%26

They didn't get their bid, but you got a deal!

 

[damcard]

I put a 5404 on it for my boy. We will slowly upgrade the bike as he gets older. It is only at 48v right now with a top speed of 20mph.
View attachment 2

 

[sandsz]

I knew it would happen eventually... my controller either broke or a hall sensor on my motor fried.

First off, I'm relatively newish to electric bike lingo but I've done a fair amount of research and am not unfamiliar with electronics in general, so I apologize up front if I get some terms mixed up or seem unknowledgeable!

When controller hooked up with no power the motor spins "clunky" like it is getting stuck.

When the controller is unplugged with no power the motor spins freely.

So either I repair the ANANDA POWER controller or upgrade to a 48V controller.
I detailed all the connections and with research have identified I think most of them plus I'm sure it is detailed somewhere else already. The motor has eight wires and I'm pretty sure I know what all of them do so I'm pretty sure I have an idea of what kind of controller I have.

I do have a question though, plus I'll use the search feature and see if this is already detailed... but how could I tell if a hall sensor on my motor went bad as opposed to a component on my controller?
This would dictate whether I go with a sensor or sensor-less controller.

Thank You!

 

[e-beach]

To test halls you need to very slowly turn your hub motor to see if the magnets are switching halls on and off. With your bike connected to the battery and the controller....and every connected as it should be as if it were running properly.

Check to see if you are getting about 5 volts to the positive and negative of the hall connector black and red wires. Something around 4.7v is good.

This test must be done with the hall connector connected, you may need to stick the prob into the backside of the connectors:

With the negative lead connected to the negative wire, connect the positive lead to one of the color hall wires (not the red positive wire) and very slowly turn the motor. The halls should turn off to 0v and then on to about 4.7v. Once you have tested one hall, repeat the test on the other two color wires to see if they are also turning on and off the halls.

 

[dnmun]

no, you burned up the controller.

i was thinking this when i first saw your title and by the time i got down here it was already toasted. nothing wrong with the halls but you will have to buy a new controller since the little ananda controller is potted in goop and cannot be repaired.

you will have to figure the new wiring sequence too so you need to buy a watt meter and install it before testing the controller you buy to replace it.

 

[swampthang7]

Hello to all: I've been reading the forum for a few days, and registered today. I'm a high voltage electrician, but dabble in computers,satellite stuff, and some low voltage toys. I'm very new to low voltage e-bike stuff. Question; the diagram seems to show ( :? 2) 24v battery connections with a DPDT switch(double pole,double throw?) . I was unaware that you could increase the voltage on one of these motors....seems like you would burn it up. If someone could help a newbie understand a few basics involving adding batteries to a setup,or post a link...I would be grateful. I have a friend asking me to help him do just this project...2 battery to 4 battery conversion. TIA, and now back to reading.