Losing power

Hello,

 

I hope this is the correct place to ask for help with a technical problem?

 

I got my bike converted at electric-bike-conversions.co.uk and it arrived about a month ago. I've only used it about 8 times and so far so good, I love it, but when I was cycling home yesterday I suddenly lost power. Everything including the LCD display and motor just turned off. When I turned the power back on it stays on for a while on setting 1 or 2 but doesn't really have any power and as soon as it's turned to 3 it also has barely any power and cuts out after 10 seconds and immediately on setting 4 or 5 (but the motor does kick in before it immediately shuts down). It seems that whenever the wattage goes up it shuts down. Battery is 3/4 full.

 

I've tried all the usual taking the battery out and checking connections (I don't know much about it though) but I'm not sure what's going on. As I mentioned I only ridden it about 8 times and have been looking after it well using a cover outside, so it's a bit disappointing it seems to have broken in some way.

 

I emailed the company last night and they haven't replied yet and I can't get hold of them on the phone as it just says they are busy and hangs up. I'm hoping they get back to me soon and can help and it's still in warranty (not sure how it works when it's a custom conversion). But is there anything I can try to fix it in the meantime or does it sound like a common problem? I've attached some pictures of all the components, in case that helps.

 

If anyone has any advice I'd be really grateful.

 

Thanks,

Jess

What is the battery voltage? When you say 3/4 full are you relying on the lights on the battery or bars on the LCD?

What is the battery voltage? When you say 3/4 full are you relying on the lights on the battery or bars on the LCD?

 

Hi, It's on the actual battery. The LCD shows 3/5.

Hi, It's on the actual battery. The LCD shows 3/5.

And I'm pretty sure the battery is 36v.

Is there a voltage reading on the LCD?

 

Your symptoms sound like battery sag which means as soon as you try and use some power it trops below the 33v LVC.

Is there a voltage reading on the LCD?

 

Your symptoms sound like battery sag which means as soon as you try and use some power it trops below the 33v LVC.

 

Thank you, I'm not at home with the bike right now but I don't believe it shows the voltage on the LCD. Just speed and mileage and power assist level.

 

If it's battery sag what can be done? Is this a fault that the bike shouldn't have shipped with?

 

Thanks for your help.

How often has it been charged? What sort of distance have you done?

Thanks for your reply. I normally charge it fully after every journey of about 15 miles and occasionally a mid-day charge after 7-8 miles if I'm planning on going out somewhere after work instead of straight home. As I've only had the bike for about a month I've probably charged it 12 times. Total distance traveled is about 130miles.

Hmmm... <scratching head> those distances are really short. How many Ah is the battery?

Yeah, haven't had it long so was surprised when it gave up on the way home! I'm not sure how to tell the Ah, would it say on there do you know?

Should be printed on the label. Or the bill when you bought the conversion.

Should be printed on the label. Or the bill when you bought the conversion.

Oh yes, sorry. It's 11Ah.

It's almost certainly a battery problem. The LCD is connected directly to the battery. If the LCD goes off, it's because it's not getting any power from the battery.

 

You can't go any further without a voltmeter. You need to charge up the battery, then measure the voltage on its main terminals, which are the two outside pins where it connects to the receiver thing at the front.

 

When you have the battery off, you could check that the connectors on each side look like they should, which is difficult to describe, but it should be obvious if something is wrong.

It's almost certainly a battery problem. The LCD is connected directly to the battery. If the LCD goes off, it's because it's not getting any power from the battery.

 

You can't go any further without a voltmeter. You need to charge up the battery, then measure the voltage on its main terminals, which are the two outside pins where it connects to the receiver thing at the front.

 

When you have the battery off, you could check that the connectors on each side look like they should, which is difficult to describe, but it should be obvious if something is wrong.

 

Thank you for your reply. The company replied this evening and it's still in warranty so they are going to take it back and repair it. I'll definitely get myself a voltmeter for future troubleshooting though, thank you!