Help! Hi all, just bought a 'broken' ebike. Some help needed. Falcoln Turbine.

[UnclePuncher]

Have you looked on the other side of the burnt contacts inside the battery fitting ?

Yes. All fine there. Still getting a reading from the burnt contacts. 35.8v

 

[Nealh]

A pic of the battery discharge pin connections.

 

[UnclePuncher]

A pic of the battery discharge pin connections.

Hard to see the black negative as it's under the bms. Also they have some kind of resin glue on them..

 

[UnclePuncher]

A pic of the battery discharge pin connections.

Can I ask what you're looking for here? Assuming just that they're soldered onto the battery.

 

[Nealh]

Just for anything out of place.

 

[UnclePuncher]

Just for anything out of place.

All good then?

 

[Nealh]

Nothing looked out of place but there is conflict polarity shorting somewhere to cause the melting contacts.

 

[UnclePuncher]

Nothing looked out of place but there is conflict polarity shorting somewhere to cause the melting contacts.

Do you think its definitely an issue with the battery then?

I'm a bit stuck as to what to try next.

 

[Nealh]

It may be in the controller who knows. All I can say is that the melting of those two pins isn't normal or right.
Are you 100% sure polarity is correct on both sides of the battery contact.

 

[UnclePuncher]

It may be in the controller who knows. All I can say is that the melting of those two pins isn't normal or right.
Are you 100% sure polarity is correct on both sides of the battery contact.

Unless the battery was incorrectly wired up from the factory. I'm the first to open this battery and all I've done is replace the bms swapping cables like for like. Plus I replaced the blown fuse.

If it was the wrong way round wouldn't it work if I connected the battery the other way round? Obviously that's not possible physically but if I connect it using wires. I tried this out of interest and it sparks on either combination.

Out of interest I tested it by first disconnecting everything else from the controller (brakes, motor, hall sensor, display) but it made no difference.

Unfortunately I don't have anything else I can test the battery on (aside from my multimeter?). I think I just have to assume it's the controller.

I'd take it to someone if I knew of anyone local to me (Nottingham) who could diagnose the problem. Googling just gives me a bunch of bicycle mechanics (I was a bike mechanic for 5+ years). I should probably try an electrician but I imagine most want to touch an ebike.

 

[UnclePuncher]

The bike was used by the previous owner (before it stopped working) so I think it's safe to assume it did work before.

Got a sneaking suspicion they jet-washed it. Should probably open the motor and have a look in there.

 

[Nealh]

The hub won't cause the electrical connection issue of melting contacts.

 

[UnclePuncher]

The hub won't cause the electrical connection issue of melting contacts.

No, I didn't think it would. But based on some corrosion I'd found in the battery I suspected they'd jet washed it. In which case the motor would need inspecting. Turns out it's fine. So if they did jet wash it there was no evidence of ingress in the motor.

 

[Nealh]

Grease is a bit sparse, it won't hurt to put a nice dollop in there and it will run quieter as well. Any non petroleum based one is good so as not to damage the nylon gears.
Other wise yes the motor is spick n span, I have ridden my bafang cst through water over the axle with no water ingress on a few occasion's. Being not under pressure no harm is done, though I do syringe white water resistant grease into the axle as best as I can.

 

[UnclePuncher]

OK. Going to try a new speed controller. Problem is I can't figure out which one to buy. I'd rather buy one with julet (waterproof) fittings so I can just plug my parts directly into it.

This Liushui one looks good

1. However it has a different battery connection (not a huge problem I can just buy the opposite side and solder it to my battery - but I don't know what connector it is - any ideas?).
2. From what I've read online it requires a particular display to work. I have a very basic display/control. Which I may upgrade at some point but not just yet.
3. Most importantly it has a 1 to 4/5 cable connection with 8 pins. Mine only has 6 pins. Can I just buy a new 1 to 4 cable with 8 pins to match? Here is a thread on Pedelecs where user Gingafuzz has the same connector (for reference)

Alternatively I could buy this one which is largely the same but it comes with more user friendly battery cables. Plus it has a light socket! Although I still have problems 1 (and potentially 2) from above.

 

[UnclePuncher]

Also as I've not actually got the thing working I was wondering, will the 250w motor actually get me up some of the steep hills round me? One opposite my road is approx 13.5% gradient (1 in 7.5 - according to Google Maps) and a couple of hundred metres long - plus there are many more hills around here. I'm around 95kg. Don't mind a bit of pedaling, just rather not break into a sweat and be out of breath every time I pop up to the shops.

 

[Nealh]

A KT controller needs a matching display, also they are current control controllers though do have a speed controller setting which needs an lcd to change it.

As your hub is only 6 wires you need a controller with the hall sensor block connector, then you should be able to just wire the 3 hall wires colour to colour.

At 95kg 15a at 36v will likely struggle esp if the motor winding is too fast, the controller will over heat at slow speeds on steep hills.

 

[UnclePuncher]

Its working. Bought a new controller in the end. That meant having to buy a new cable to connect the brakes, display etc.... Which came on a very slow boat from China.

Slight problem the new cable it has 3 pin connections for the brake levers and my levers are 2 pin. Could just buy some new levers but most sellers don't show which connectors the brakes have. So I was thinking of just hardwiring the ones I have. Does anyone have a pin out of the brakes/cable? I'd imagine its just a case of wiring the same coloured cables together but would rather check before I start cutting cables. I'm at a loss as to what the purpose of the third cable is.

Obviously the bike works fine without the brakes connected to the electrical system but of course it'd be better if they were working.

 

[UnclePuncher]

Might have just answered my own question.

What does the red pin do?

 

[sjpt]

I'm at a loss as to what the purpose of the third cable is.

Probably a two way switch, so common (first) wire is connected to one of the others (second) when brake pressed, and to the other other (third) when brake released.