Technical

[Ken FergusonKeymaster]

Hi Mark

Trip switch has been sent.

Ken

[AyesongsParticipant]

Thanks, Ken.

I’ll let you know how I get on.

Mark

[Ken FergusonKeymaster]

Ho Albie

This is not straightforward and it is not at all analogous to a fuel tank in a petrol vehicle because the discharge profile of every battery is different.

The remaining capacity of a battery is measured in KWh but this is impossible to measure so the instrumentation uses the drop in the voltage of the battery as a proxy. But that’s a bit like trying to measure water temperature by sticking your thumb in. So the change from four bars to two does NOT mean that the battery has used half of its capacity.

So how do you know how many miles you have left?

Actually I don’t think you can- you will only know you have run out of juice when the bike stops and for various reasons this might be at a different place each day. I have never had to push one home yet but I do tend to err on the side of caution. There are things you can do to extend range- charge the battery in warm conditions, drive more slowly and decelerate not brake. The last tip in particular should make a lot of difference.

Of course there may be a fault in your battery- if you think there is let us know and we will test it and replace if necessary.

[AyesongsParticipant]

The replacement trip switch arrived this morning with the first post since the Beast from the East. I’ve installed it and everything seems to be fine electrically. Unfortunately conditions aren’t good enough here for a test drive just yet but I’ll do that as soon as I can.

Would you like me to send back the original switch for testing?

[albiemParticipant]

Thanks for the information Ken.

I have no doubt this cold weather isn’t helping but I still feel somethings not right. After only 4 miles the speed drops to 24/25, its as if the battery is already losing power after a short trip. I will charge the battery inside and see if that makes a difference but I’d rather not remove the battery daily to charge inside. If this doesn’t help I will contact you to send the battery back for testing.

Thanks

[Keith ByattParticipant]

Albiem,
What temperatures are you operating the bike in? As the temperature gets down to Zero, you will already have lost 50% capacity from a full charged battery at 20 deg C. It is the science of the battery. As soon as you start using it the off load oltage will fall dramatically, and the “fuel gauge” will reflect that. Battery technology has not yet invented a cellthat will perform well at sub zero temperatures at a price that people wil pay

[AyesongsParticipant]

I’ve replaced that trip switch and taken the bike for a short run of a mile or so and it seems to be behaving itself. I’ve some business in town tomorrow which will give it more of a workout. If that goes well, I’d say we’ve fixed it.

I may have a post mortem on the old switch later.

Thanks, Ken.

[albiemParticipant]

I’m operating the bike in temperatures anything between 0 - 8 degrees I guess, UK weather. Let me see how I get on with the better weather and report back.

Would you expect the 27mph to be the correct top speed at full charge? What everyone else’s experience? I weigh about 80kg.

[Ken FergusonKeymaster]

Hi Albie

This is correct.

The specification on the bike states a top speed of 45kph which equates to 27.9mph. It is a digital display so of course it will state 27mph.

Ken

[Brett MarriottParticipant]

Hi, so I’ve only had my model 15 6 days and I am already having issues. My primary issue is to do with the chain. It just won’t stay on and is really difficult/ fiddly to reattach. Does anyone else have this issue. I have maybe covered 20 kilometres and it has come off 3 times.

[paulhanson47Participant]

If going down a steep hill I would assume the motor would cut out at 15 MPH would the bike freewheel faster than 15 MPH or would the motor slow the bike to 15 MPH.

Erider 15

[Keith ByattParticipant]

The motor goes off load, and you will freewheel as fast as you like. But if you apply the brakes a little, the motor starts to regenerate power and charge the battery a little. Depends how long and steep the hill is!

[Ken FergusonKeymaster]

Hi Brett

That does not sound right at all. If you are experienced with bike chains it may be possible to solve the problem by removing a link but the simplest solution might be to send us an email and we will send you a replacement chain

Ken

[albiemParticipant]

Morning Ken\Keith,

I’ve been meaning to report back for a little while now. Since the weather change the bike has been fine, no dramatic drop in battery or speed and works well for my requirements. Its steady at 27mph both to and from the station daily after a nightly charge.

In terms of the winter months would you just advise to remove and charge the battery in a warmer climate?

Thanks
Albie

[Keith ByattParticipant]

Battery will accept a fuller charge if not too cold so anything from about 10 deg C upt to 25 deg C should give a fuller charge. But of course when in use in low temperature, the capacity will be reduced. Thanks for the feed back, but note I am just another user and not employed by Erider!
In winter months if you keep the battery in the warm until just before you use it, it should retain its temperature and perfomrance for a while depending on how cold the outside temperature is.

• This reply was modified 1 year, 3 months ago by  Keith Byatt.

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