Ebike runs backwards

General Discussion about electric bicycles.
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Looncan   1 mW

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Ebike runs backwards

Post by Looncan » Oct 25 2015 3:46pm

i purchased my ebike 1000W rear-wheel from ebay hooked them up to the lipos all indications light up ready to go, i twist the throttle and it goes backwards!!! why is it going backwards, i can't seem to make any sense of this, there was me thinking the lipo hook up was going to be the trickiest part of this

wish i bought the front wheel now, i would just be able to flip the wheel but since this is a rear wheel i can't exactly flip the wheel :'(

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spinningmagnets   100 GW

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Re: Ebike runs backwards

Post by spinningmagnets » Oct 25 2015 4:27pm

There are typically three fat motor phase wires coming out of the axle. Also, there are five tiny wires that terminate in some kind of a plug, those five are the hall-sensor wires.

Now that we have that out of the way...I'll bet if you switch the blue and green motor phase wires (or any two of the fat phase wires) then the motor will run forwards.

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Looncan   1 mW

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Re: Ebike runs backwards

Post by Looncan » Oct 25 2015 4:37pm

the little yellow box with the nuts that screw yellow/Green/blue? if i switch them around it'll work! i thought the reason for the colours was so it had to match, so your telling me to mix the colours up if i get you straight

i just don't want to explode my lipo batteries (i'm a newbie) by mixing those colours up, too late tonight to see if it'll work i stay in a flat with neighbors, my family would likely choke me before my neighbors

Image

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Sunder   100 MW

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Re: Ebike runs backwards

Post by Sunder » Oct 25 2015 5:08pm

You only need to swap two out of the three.

Think of it this way. Draw "A" "B" "C" around a circle. The correct sequence to move forward is ABC, or BCA, or CAB. Doesn't matter where you start as long as you get that order.

Now imagine if ANY of the wires were out of sequence. What's the possibility? If it went A -> C then the only next possibility is B - which creates the sequence ACB - which you will notice is one position rotated from CBA - or the exact reverse of what you want. Again, it doesn't matter where you start. If it was B, then you'd go to A then C - again, exactly reverse. Thats why if it's going in reverse, you can swap any two wires around, it doesn't matter which, and you will get a right combination. The controller doesn't care if you are starting at "A" "B" or "C", it just needs them in the right order to make the wheels spin in the right direction.

There is no LiPo fire danger from swapping the wires around, as long as you don't short them. But then, that danger was present when you first installed the wires. Obviously do it with the system powered down (disconnect battery, twist throttle for a second to drain any remaining power).
eBike: Q100H on 16S with Phaserunner FOC Controller
eMotorscooter: Vectrix VX-1 on 36S
eCar: Mitsubishi Outlander PHEV... Waiting for warranty to expire
eHouse: Still on grid, but with LTO batteries and 3kw LF inverter...

After 5 builds, the best advice I can give, is start with high quality products. I prefer http://www.ebikes.ca

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Looncan   1 mW

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Re: Ebike runs backwards

Post by Looncan » Oct 25 2015 5:17pm

not to insult you but when i read you r post i seen

Image


my ebike is going in reverse when i twist the throttle, the first response told me to change the green and blue, wires and i asked was that the yellow box with the G/B/Y wires and if so are you telling me to mix the colours up and that will stop my ebike going in reverse

As i'm a newbie the idea of me not following the colour coordination is confusing to me and it's midnight (2am) so i can't test a loud ebike i'll wake people up

but the idea that the matching colours in the yellow box seems strange to me, isn't that why there colour coded to begin with


i'm aware newbies insulting veterans never goes down well (^o^)

Voltron   1 MW

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Re: Ebike runs backwards

Post by Voltron » Oct 25 2015 7:12pm

Yes....he is saying swap the colors. And no, it's not too unusual that the colors don't match, even on something sold as a complete kit.
And while you're at it, once you find the color combo that works, ditch the yellow junction box piece and go with some other connector for the wires like bullets or Andersons or something... I've seen a few of those melt from the poor connection.

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Sunder   100 MW

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Re: Ebike runs backwards

Post by Sunder » Oct 25 2015 7:38pm

Thats fair enough, though I suspect if you did just take the first step of drawing a circle and writing a, b and c you'll very quickly see what I mean.

You're now stuck in a spot where you're a bit too skeptical to blindly follow instructions and not quite at the point of understanding explanations.

Just take spinning magnet's advice for now and worry about it later, if at all.
eBike: Q100H on 16S with Phaserunner FOC Controller
eMotorscooter: Vectrix VX-1 on 36S
eCar: Mitsubishi Outlander PHEV... Waiting for warranty to expire
eHouse: Still on grid, but with LTO batteries and 3kw LF inverter...

After 5 builds, the best advice I can give, is start with high quality products. I prefer http://www.ebikes.ca

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Looncan   1 mW

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Re: Ebike runs backwards

Post by Looncan » Oct 25 2015 8:18pm

Thanks guys you've been a great help, i can't test it at the moment (late at night) but i'm sure your info will be more than suitable for me to fix this, i get easily confused so it's awesome places like this exist ˚◡˚

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spinningmagnets   100 GW

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Re: Ebike runs backwards

Post by spinningmagnets » Oct 25 2015 8:33pm

Yeah, the three fat wires that go into the yellow box. You can swap them all around and it won't hurt anything. Start by swapping the green and blue wires. Unplug the green, put the blue wire into the green socket, then put the blue into the only open socket left.

Report back with the results. Some motor assemblers are hungover on Mondays and get the blue/greens wire locations backwards.

John in CR   100 GW

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Re: Ebike runs backwards

Post by John in CR » Oct 25 2015 9:51pm

Looncan,

It's not quite as simple as just swapping 2 wires. There are 6 valid hall/phase wiring combos. 3 reverse and 3 forward. Invalid combos can also spin the wheel, and riding with an invalid combo can damage the motor or controller or both.

As long as the reverse is nice and smooth sounding (listen as it starts to spin), then it's most likely a valid reverse, and you will need to make a change to both the phase wires (the thicker 3) and the hall wires (the thin yellow/green/blue). Simply change 2 any 2 and only 2 phase (or hall) wires. Then find the correct combination of the 5 remaining hall wires (or phase if you swapped just 2 halls above). Use only small pulses of throttle when trying the different combos, and no it's not dangerous with only small pulses. Personally I use alligator clip wires on the phase wires till I find the right combo and just swap 2 of the halls. That way I know only low current is passing. When trying new combos only swap 2 at a time, which is easier and easier to be orderly.

This is the easiest method and guaranteed to work, so easy that I've done it with non-color coded wires and could do it blindfolded on a dare. Figuring out wiring combos is consistently the most common thing that many ES members over-complicate.

On many motors some combos can spin the motor, but aren't correct. IME these "false positives" are always in the opposite direction of the correct combo for a given hall or phase combo, and IME they sound rough compared to the correct combo. False positives will also have high current, so if you have a multimeter that can measure current it's always good to check no-load current once you think you have the right combo until you have more experience and can definitely tell the difference by the sound. If you can't measure current, another telltale sign is low torque, so if you try the bike and acceleration is very poor, then stop immediately so you don't damage the motor and go back to the 2nd paragraph above. Quite a few people have ridden their bikes that way and burned up motors or controllers.

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Re: Ebike runs backwards

Post by d8veh » Oct 26 2015 7:18am

Assuming smooth backward rotation at present, you switch the yellow and green phase wires (thick ones) and the yellow and blue hall wires (thin ones in the white block). To get the pins out of the block, you need something very thin, like the smallest jeweller@s screwdriver. You have to hold down the barb on the pin from the front while you pull the wire from the back to get it out.

The colours don't always go colour to colour. It depends on which controller and which motor you have. If you don't have a disc brake, you can, of course, turn the wheel round/ Finally, just to cover everything, I have seen people with their forks back to front too!

John in CR   100 GW

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Re: Ebike runs backwards

Post by John in CR » Oct 26 2015 1:39pm

d8veh wrote:Assuming smooth backward rotation at present, you switch the yellow and green phase wires (thick ones) and the yellow and blue hall wires (thin ones in the white block)...
If that works, there will be some luck involved, though the Chinese manufacturers don't seem to be completely random. The odds of getting it right on the first try just swapping 2 phases and 2 halls blindly to change direction are 1 in 5. If it doesn't work with d8veh's recommended swap, then keep either the halls or phases static (whichever is harder to change) after that initial swap, and try the remaining 4 possible combos of the other set (halls or phases). Beware of false positive results that do spin the wheel and typically have more noise or need a nudge of the wheel to start.

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fechter   100 GW

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Re: Ebike runs backwards

Post by fechter » Oct 26 2015 1:56pm

Some controllers have a reverse feature. You might check for that before swapping around the wires.
If equipped, most have a pair of wires that you would either connect or not connect depending on which way you want it to go. With even more luck, the wires would be labeled in english.
"One test is worth a thousand opinions"

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Looncan   1 mW

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Re: Ebike runs backwards

Post by Looncan » Oct 27 2015 2:24am

Yeah it worked i switched the wires around and success! though i was riding around with less brake had to disable my rear wheel brake only using my front wheel brake and i broke my chain the week earlier so i was off to a rickety start to say the least but it was 4:00am and a full moon up here in Scotland so i enjoyed my little 1st hour on my ebike, gets nippy, gonna have to buy a facemask or grow a beard but this 150quid bike is costing me a fortune on repairs, lol

Bike repair man is gonna look at me weird next week when i ask for 200 quid of repairs on my 150 quid bike (Ͼ˳Ͽ) but i've had it with my chain and brakes

EDIT
-----
Oh i matched it

Y G B
B Y G

incase any people need help with it in the future

pawepie   100 mW

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Re: Ebike runs backwards

Post by pawepie » May 18 2018 9:36pm

Did you also swap the hall sensor wires, or just the phase wires? When I swapped my phase wires with your suggestion, I get it spinning forward now, but it doesn't seem to reach the same top speed. When I match the hall sensors, the motor does not run. I'm actually trying to run a DD motor backward because that is the only way I could get a disc brake to fit.
Looncan wrote:
Oct 27 2015 2:24am

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amberwolf   100 GW

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Re: Ebike runs backwards

Post by amberwolf » May 18 2018 10:15pm

Well, looncan hasn't been back in more than three years, so probably won't answer you.

But I'll repeat some of whats in the thread above; perhaps it will help.


Generally colors won't match between motor and controller, so there's a thread for Determining The Wiring For A Brushless Motor that will help you find the right phase/hall combo, if your controller does not have a Learn wire.

John in CR also states one of the methods in his post above.

BTW, if your controller has a Reverse wire, you can simply connect that up if you had it working in the other direction just fine.

If you're not absolutely certain it was already the right combo (again, colors don't usually match), do the tests in that thread to find the rignt one.

Regarding the disc brake fit, that doesn't make sense, since the brake mounts for motors are on the same side as regular bike hubs (left), so unless there's something wierd about the bike frame its on, putting the motor on backwards will put the disc mount on the wrong side of the bike entirely.

aroundqube   1 kW

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Re: Ebike runs backwards

Post by aroundqube » May 19 2018 1:07am

link to Determining The Wiring For A Brushless Motor ( it's in the ES Wiki ) https://endless-sphere.com/w/index.php/ ... less_Motor . Note that its best to be measuring the Amp draw of the motor while testing each wiring combo. A false positive will turn in the desired direction, but will draw too much.

david harding   1 µW

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Re: Ebike runs backwards

Post by david harding » Aug 08 2018 10:07pm

There are 5 hall sensor wires but do not switch around with the RED or BLACK ----Those are plus & minus power supply for the sensors

markz   100 GW

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Re: Ebike runs backwards

Post by markz » Aug 08 2018 10:53pm

Some people can do this game of swapping wires and finding correct combo's with their eyes closed.
:wink:

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dogman dan   100 GW

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Re: Ebike runs backwards

Post by dogman dan » Aug 09 2018 7:06am

Well, now that this thread is back up top, one thing that is more common now than it was, is self learning controllers.

If you are reading this now, look to see if your controller has self learn, or self study wires.. Two wires, with a plug to connect them to each other. Connect, let the motor start turning, then disconnect. Now your controller runs forward.

Most of this type controller will have all three fat wires the same color, btw.

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