ZapGuy's Electric Bike

ZapGuy - Welcome to the e-bike club!

I had a similar experience. Bought my first e-bike of Craigslist without knowing much about them. Mine was running but the batteries had been abused and neglected. It was a 36v system with same motor as yours. I bought a desulfator off e-bay that helped the old batteries some. I'm still able to use them for short (<5 mi) rides The seller is no longer listing them but here is the link to the one I bought:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MEWNX:IT&item=300229535515

I also bought some new batteries from this e-bay seller:
http://cgi.ebay.com/36-volt-electric-bicycle-motor-hub-kit-battery-pack_W0QQitemZ320300364313QQcmdZViewItem?hash=item32030036431...
These batteries should fit in your battery case. All you'll need to do is fab up a jumper wire with some slip on connectors to wire in the 3rd battery. Use 12 gauge wire or larger. You can buy the connectors at ACE hardware. I soldered mine on because they kept slipping off.

A lot of people dis the sealed lead acid (SLA) batteries. They're heavy, they don't provide all the amp hours they should if you draw them down rapidly, they don't last as long as others, and you need to charge them immediately every time you ride if you want them to last. This is all true, but for my purpose, a relatively short 3 mile commute without any killer hills, they are by far the most economical battery. I don't discharge them below about 80%. With this light duty cycle, I expect to get at least 500 charge cycles out of them. SLA is a good way to get started if you have any doubts about this whole e-bike thing. Once you've sorted out what you really want your bike to do (and if you find SLA isn't doing it for you), you may decide it's worth the investment for more exotic and expensive battery chemistry.

The chargers sold by WE (Cansai) are junk. I bought a scooter charger and just soldered on a RCA socket that matched my WE battery pack. It has the same charging cycle as the Cansai, puts out more amps, runs a lot cooler, and seems to be better quality overall. Here's the link:
http://cgi.ebay.com/ebaymotors/36-Volt-battery-Charger-for-Gas-Scooter-ATV-Dirt-Bike_W0QQcmdZViewItemQQ_trksidZp1742Q2em153Q2el1...

Your hub motor is a Wilderness Energy BD-24, which I've read is the exact same motor as the BD-36. If so, it should run on anything between 24 and 48v. At 36v, you should get a little over 20 mph on flat ground with fully pumped up tires. It still won't pull you up any steep hills without pedaling, but it will make the pedaling a whole lot easier. It is a brushed motor, so be sure you're looking at controllers for brushed motors. Brushless ones are entirely different. BEWARE - when wiring up your new controller, pay special attention to keeping the positive and negative straight. The wires coming out of the old WE controller have the colors reversed on the two that I've seen. Black is positive on the controller side of the connector. The colors are right on the connector coming out of the battery pack.

Your throttle may be OK or not. I really don't know how to check them. Some work off variable resistance and some have hall sensors that need some excitation voltage to be able to work. The throttles work on 5v, so don't try hooking it directly to your battery pack. If it has hall sensors, possibly you could feed it a 5v signal and check to see if the voltage changed as you moved the throttle lever. There's probably some info on this board somewhere about how to check a throttle out. If not, check out the discussion boards here http://endless-sphere.com/forums/

If your batteries are old and with unkonwn care and feeding, I wouldn't try to integrate a new one into the pack. You would have an imbalance in charge as soon as you started using them and you wouldn't get full efficiency from your new battery.

I can't tell from the pictures if the dropouts on your forks are steel or not. If not, be careful with upping the voltage. There are lots of stories about the torque from the motor breaking the relatively soft aluminum dropouts and the front wheel departing the bike. Pay a lot of attention to the tightness of the bolts and the condition of your dropouts. Better yet, get a torque arm to take some of the stress off the dropouts. The one near the bottom of this page looks like the best one available to me:
http://ampedbikes.com/buynow.html

With the 24v setup, you could probably run with the horn button without damaging things so long as you don't bog the motor down. Pedal first when you start out and don't let it bog on the hills. If the motor is not getting hot, you won't damage it. You might draw your batteries down faster than is healthy, but I think you've pretty much written them off anyway. The motors can get pretty hot, like hotter than you want to hold your hand on, without damage.

Hope you enjoy your new bike. It looks like with a little work, you could have a keeper there.

You might be happy with 36v if your hills are not really steep and long. Personally, I like to pedal, but I don't like to arrive at work dripping with sweat. With 36v I find I can take moderate hills at 10 to 12 mph running in on the middle front sprocket and small rear sprocket. I usually just run on the small rear sprocket and switch between the big and middle sprocket on the front. On the flats, I cruise easily at 23 to 25 mph. I could go faster if I had taller gearing, but that seems fast enough on an unsprung bike. Even if I only peddle a minimum amount, I'm always moving fast enough to get a good breeze and stay comfortable, even in 100+ heat. It's a dry heat here in Redding, though. The bike is definitely pulling a lot more than it's own weight. I can easily accelerate across an intersection as fast as the cars next to me. The front wheel will sometimes start to spin when I'm riding up a steep dirt trail. The motor is putting out a significant but not overly abundant amount of torque. It will stall on steep hills and you can overpower it by really clamping on the brake (if you ever had the throttle stick or something). I'm pretty happy at 36v for kind of riding I do.

If you go with more than 36v, you're probably going to want to look at something other than SLA. 4 SLA cells are just too heavy to lug around unless you build a special rack for them. Search for "Ping" on this site and you'll find a lot of info on his line of lithium batteries that you can buy direct from him in China or sometimes off of e-Bay. Most people swear by his stuff and he stands behind it. There are apparently some substandard/borderline scam battery vendors operating form China at present, so be careful who you are dealing with. If you're really looking for a project, you can find info on how to build up a lithium battery pack using high-end electric drill batteries. Probably wouldn't be any cheaper than you could buy a Ping pack for, but it could be higher performance. Lithium is pricey. A 48v pack would likely run more than you paid for the bike.

Check out this thread for some good info on running a BD36 at 48v:

http://visforvoltage.org/forum-topic/bicycles-and-pedelecs/811-wilderness-energy-bd36-running-48v

That is the Wilderness Energy BD motor for sure, Link and a few others are running them at voltages above 48v. I don't think its a real good idea to run them too hard for long distances or time though. I melted one this summer riding for one hour in extreme hot conditions. Now that cooler weather is around hot motors will not be a problem for quite awhile.

It will go around 24mph on 36v and 29 mph at 48. If you read the threads you will get a lot of info on 48v but as long as the controller is ok with it, it's a good fast motor at that voltage. The stock WE controller is happy at 36v or 48 v. The trade off with sla's is the weight of 4 batteries.

The lithium batteries at ebay are great, but only needed for long rides. With 3 sla's and wide open throttle riding, you will have around 6 mile range, and up to about 9 miles if you keep it under 15 mph.

The forks may be a problem, big motors and big voltage on medium motors can break the dropouts. Most folks running the fast stuff use a torque arm. Ampedbikes has the best ones I've seen. Others report normal voltage is no problem for these forks with motors like yours. Normal, being 36v. I tend to agree, BUT, one little bubble in the casting on aluminum, and one fine day you could go one way and the wheel the other. If that happens a touque arm may hold it together just long enough to stop safely. The thing about the alloy forks is when they break, they smap like glass, no warning at all. I wouldn't park the bike exactly, but I'd get a pair of torque arms or a steel fork on it soon. Another option that reqires a bit of fabrication is making it a rear hub. To do that you need a rear hub crystalite motor cover. A few new holes drilled to make it fit, and a freewheel can be put on the hub and run it as a rear motor.

Chargers are a problem. I went trough several before I finally got two, one stays at work, that are reliable. Scooter parts retailers online, and ebay are good places to look for one, and just rewire the plug to fit what you have. A cheap voltmeter from a hardware store is kind of a must have tool to check on battery health and wire polarity.

This motor is getting a bit rare, I haven't seen new ones for sale lately. But controllers for other motors that are brushed are avaliable in many places. There are many retailers for WE and some still have parts, like brushes and controllers for the BD 36. Using the controller is best for the health of the batteries, but if the bike was only used on flat ground, the go button method would work on 24v. At 36v, things like switches start to melt pretty easy. Other controllers for brushless motors will not work with this brushed motor.

Another option before you invest more in SLA's, which I do not see mentioned much at all on the forums are NiCad batteries. They can be found very cheap if you look around. I recently purchased a BL-36 and had been using 3x12v 18ah batteries, and they do a great job. I have not even approached finding their limit on range, but they weigh about 39 lbs, so I had to find another solution.

NiCad's!

I found a great deal on some 14.4v NiCad tool batteries. I bought dozens of them and reassembled into my own homemade 48v 1.5ah battery packs with tape and am charging them with a 48v Nimh/NiCad charger I found on powerstream. I just rode to work today for the first time, on just 2 of these packs and averaged 25mph for a short trip of 2.5 miles. I found out once I was in my office that I was really only running on one of them. The other had come unplugged at some point and was not even warm.

The batteries in the tool packs are sub c and are 1500mah. So to get a total of 9ah you would need 6 battery packs. Which at 3lbs a piece weighs in at roughly half the weight of the SLA's I was using and 12v more at 48volts.

I actually was going to go ahead and try 60-72v with a Crystalite controller, but had to scrap that plan for now, because I am not sure how to charge a 72v NiCad pack and have not been able to find a charger over 48v. Also the BL-36 hub I have appears to be a newer model and only has three wires from the controller and I have no clue how I would adapt that to a 72v Crystalite controller if my WE controller burned up. I already made a 72v pack just because it was so easy (5X14.4). I'd like to figure out how to rig up something with it for a booster to use on hills or starts. Challenges for later, but if anyone has any ideas . . . . please let me know.

Good luck with your new project.

Whome

That will do the trick. Once it comes, I hope you aren't running it on the aluminum forks. It will have some good power at 48v, enough for it to hurt if the wheel leaves the bike.