Help! Evora folding bike problems

[Martyboy]

I bought two Evora folding bikes from bicycles 4U about four years ago. This company has now ceased trading.
Excellent value for money and they helped us with two spare batteries which have lasted reasonably well.
Both biked have now begun to play up. One sets off on its own – which can be quite alarming – and the other now shows no lights and is in operative even with a full battery.
Has anybody fixed one of these things?
I wonder if it is something to do with the control box which I have located in the main frame. Are these fixable?
If I can’t get going then I will have some spares for anybody who is interested!

 

[vfr400]

We need a lot more details. Show some photos of the handlebars and other parts so we can see what electrics it has.

Please describe the circumstances under which the one goes by itself. If it's when you push it, it's because your freewheel needs oiling.

 

[Martyboy]

Thanks, I have uploaded some photos now to this post.
The Evora has a throttle so can go without peddling. It has, occasionally for the moment, engaged the motor without either the throttle being used or with use of the peddles. This has happened when the bike is stationary. However, I will oil the freewheel. Where's that!
The other bike is just dead and the wiring is extremely complex as you can see from the picture. But the wiring looks brand new and I can not see any obvious wire/contact breaks.
I suspect the motor controller but I suspect this is likely impractically expensive to replace or not available.

 

[vfr400]

I still don't understand what you mean by the one going by itself. Are you saying that if you leave it leaning against a wall and walk away, 5 minutes later it'll drive itself away? If not, what makes it drive itself?

The wiring is standard and very straight forward. Before doing anything, make sure that the motor connector (if you have one) is all the way to the marked line, not just in tight.
These are the basic tests you should do after connecting everything up and switching on.

1. Measure the voltage at controller's battery connector. Obviously should be battery voltage.
2. Measure the voltage on the 5v rail. You can measure that between any ground (black) and any of the reds going to throttle, PAS or motor halls.
3. Check throttle signal wire, which is the one that's not red or black. Should give about 1v to 4v when you twist the throttle. If there's more than one wire., your meter will find it.
4. Check that the PAS is pulsing. Measure the PAS signal wire while turning the pedals slowly. Should pulse 5v on and off every time a magnet passes the sensor.
5. Check the motor hall signal wires (blue green and yellow). They should each pulse with 5v going on and off as you rotate the wheel BACKWARDS.

If your bike passes all those tests, it will work. The test that it doesn't pass shows where the problem is.

 

[Martyboy]

You have been very kind with your advice and I have looked at the bike this morning.
I don't think I have a motor connector. A wire disappears into the hub.
Normally, when you switch on, the battery status lights on the handlebars light up. Now, they don't.
I'm afraid my technical competence is limited and I'm not sure about all the technical terms you are using; PAS/Rail, but I have checked all the connections and fuse but can not find anything amiss. All the wiring is very clean and tidy. I have not been able to carry out the diagnostics you have suggested.
I am still thinking that either the throttle/switch on/off or the motor controller has failed.
I have tried to investigate the throttle/switch on/off device but have not been able to dismantle.
The motor controller is identified by a serial number, (in picture), but, even if I can find the right controller replacement, (and there seems to be a wide choice of these at reasonable prices), there is such a jumble of wiring that I would not be competent to fit.
Are there professional repairs that would look at the bike? I don't want to throw away something that has lots of life left in it.
Thanks

 

[Nealh]

If the bike with the throttle kicks in/straight away when you switch it on then the most likely fault is a an intermittent wire fault/wire brake on the throttle wiring. Disconnect the throttle to prove the theory.