My "new" ebike

My 2nd ebike was made from a childrens bike; the third had a full suspension but was too big; I realized that I could get light weight, small size, and a suspension from a folding bike. I also wanted to try a hub motor. I searched craigslist, and found a folding ebike. What luck? It's an Eton Eco and it's pretty heavy (52lbs+20lbs for the two 12v 12ah SLAs) but it will be fun to play around with. I can't find any useful information on this bike via Google except that the hub motor is 400w. It's pedal first. The batteries are doing OK but not great... I pulled the pack apart and the batteries are GS PE12v12, just generic SLAs. I haven't pulled the cover off the controller because I have to remove the cranks and I'm going to do my taxes tonight

Now that's cute. What are the wheels, 20"? What's the little red button on the handlebars? Perhaps after your taxes you can pop open that hub for us and tell us what's inside. Brushed or brushless, geared, etc. Some rpm/v info would be neat.

Of course, if you upgrade the controller, it might make a fun little wheelie machine. Just make sure it doesn't fold on you!

"E-Ton"... at least they had a sense of humor about the weight.

That looks like a nice ride for getting around the big city; I like it. It's got fenders, which is more than I can say for my ebike.

Is there 70mm or so between the two halves of the plastic battery case?

The reason I ask is: If it were mine, I would consider swapping the SLAs with rows of Moli cells.

disadvantage

Ok, I pulled the bike apart yesterday.

The wheels are NOT 20"... they're like 18" or something unusual like that. The other weird thing was that the cranks are shorter than normal, but only by about an inch, and the bolt holding them in place is not a left handed thread like on other bikes I've worked with.

The tires are made my Maxxis and labeled "for electric bicycle use only." I thought that was cute.

The rear triangle is extended to hold the battery and controller. The controller is small and in a box labeled E-Ton. It has a strip of 6 terminals on one side. All the chips on the PCB have the lettering on top scratched out and sharpied. The 6 FETs and UVW lettering on the terminal strips means the motor is 3 phase. It has hall sensors too. Many of the components are rated at 25v, so I don't see a 36v upgrade in the future.

The left hand grip has a twist for the derailleur, and the right grip is a throttle. There is a red cutoff switch below the throttle which turns the motor controller off. The brakes have switches that go back to the controller.

The controller won't let the motor spin unless 5mph or so has been reached. Then it's possible to stop pedaling. I could pedal faster than the motor could push me.

The battery box contains two SLA PE12v12 wired in series. The wires go to a fuse and then to a key lock. Not quite sure what happens in that area as I didn't trace it, but a the bottom of the box there are 3 wires, red blue and black that have an anderson connector. This connects to another anderson connector that is wired up to another connector that connects the batteries to their base when the box is dropped into its receptacle.

My set of lithiums would fit inside the battery box, but they're not doing well. This bike really needs a rear suspension, and the frame is very heavy. I may find another frame and transfer all the pieces to it. Additionally, this controller is pretty annoying. Someone asked about using a Kollmorgen controller on a hub motor, and though the Kollmorgen controller kind of sucks, you can probably see how it is better than the E-Ton controller.

All the chips on the PCB have the lettering on top scratched out and sharpied.

Click to expand...

Mmmm Chinese quality.

So, pedal-first 6 FET bruslhess controller... Bike tops out at <15mph, it sounds. Wonder what the limiting factor there is. Current limit? (like... 10amps? ) Reaching the motors top speed? Gearing problem, etc?

If you could get a CycleAnalyst or somesuch wired in there, we could get some really interesting information. I especially would like to know the motor unloaded speed at 24v and the controller amp limit.

And... I wonder how much power you could shove down that motor's throat before it overheated.... or with extra cooling. That sounds like a fun project.

I'd love to hook up another controller; but I haven't got any except the Kollmorgen. I was working on my own but didn't finish.

I do have an ammeter and my Fluke so I can definitely check the current limit. I can hook the batteries up to the Kollmorgen to see if I can pull more amps using that.

In regards to motor unloaded speed, I can lift the rear off the ground and get it spinning fast enough to get the controller going. If it has a current limiter (which I highly suspect it does) I guess it won't be too useful.

You could possibly upgrade that controller. Most of the components run under 15v no matter what the battery voltage is. The main cap, the FETs and the voltge regulator (I assume near the Eton yellow thing) are the parts that need to handle higher voltage.

Can you read the numbers off the FETs? It might be posted somewhere in the archives....

That copper U shaped loop in the middle is your current limiter shunt. Easy enough to mess with that, but not recommended if the FETs are going to blow.

Hey Fechter, good to hear about upgrading the controller. I didn't read the labels on the FETs. They are amply glued to the bottom of the PCB, and without firm intention to upgrade the controller I decided I'd rather leave them be for now. Anyway, since every other chip had the model number scratched off I figured it would be probably pointless. I have plenty of FETs lying around, but no batteries I would permanently mount. Though it might be fun to hook my two 38ah SLAs up...

What's the best cheap 3 phase controller that could handle 48v?

? not sure.
Look here:
http://endless-sphere.com/forums/viewtopic.php?f=11&t=2267&hilit=ebay+brushless

Those look like they have possibilities.

Yeah, this is the cheap brushless controller that folks have been having luck with: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=300179089067&ssPageName=MERCOSI_VI_ROSI_PR4_PCN_BIX&refitem=190152918093&itemcount=4&refwidgetloc=closed_view_item&refwidgettype=osi_widget

Looks like they've run that controller up to 60v.

In regards to motor unloaded speed, I can lift the rear off the ground and get it spinning fast enough to get the controller going. If it has a current limiter (which I highly suspect it does) I guess it won't be too useful.

Click to expand...

The speed you get with the wheel off the ground is the motor's maximum speed at that voltage. It allows you to calculate how fast it could go with a real controller, or at a different voltage. These are nice things to know when the moor is completely unknown. Of course the controller will have a current limit. But, with a different controller, you should be easily able to reach close to the motor's unloaded speed - I suspect it can't be very high at 24v.

Though it might be fun to hook my two 38ah SLAs up...

Click to expand...

What are those, car batteries? Marine batteries?

My two 38ah batteries are from electric scooters (big ones). They're past their prime for scooter usage I'm told, but they work just fine for my bike. They max out my ammeter so I can't tell how many C I am pulling. I really ought to invest in at least one pair of decent batteries.

Thanks for the controller link definitely more affordable than the $150 controllers I have seen. And easier than finishing my controller...

I've searched the entire forum and I'll be looking for a couple more to search too, but this one has a real posting about the Eton Eco.

Yep, it's a ton, alright. A friend got a ridiculous deal on two of them, nearly new, with kaput batteries. He got a little hosed on the price for replacement batteries, but one of the bikes works. The other one doesn't.

I did some parts swapping and determined that it's something in the motor of the bad bike. The LED power/low power indicator flashes rapidly as soon as the rear wheel is spun, and the eloquent handlebar label says that's an indication of a disconnection.

As noted, it's a pedal-first motor/controller. There are the two power leads going to the main motor cable, and a bundle of smaller ones, which I'm guessing are the sensor wires?

Is there a test one can perform with a DMM to determine the failure? Even if I can figure out the failure, is it likely something that could be repaired? I understand that caution needs to be exercised when cracking the case on a hub motor, specifically when replacing the cover, but I won't open it up if there's nothing to be corrected.

Thanks in advance.

It's been two years since your post but FYI there are three wires heading to the motor for power; and 5 for the hall sensors.

You can try attaching a sensorless controller and seeing if it will run.

Or just take the case off. It's really easy on this motor. You need a screw driver and two chisels. Look for windings that have the insulation melted off. You can also check the resistance between each winding, look for a short.