Trouble with charging my phone via my motorcycle

[Arthemius]

Hey there,

I wanted to be able to charge my phone whilst riding so to never have an empty battery. I also wanted it to only charge when the bike was on. I have succeded in this. I used a female cigarette lighter used in cars. I hooked one wire to the frame of the bike and one to the fuse box. I checked which ones gave power only if the bike was on. I then put a usb charger in the cigarette lighter. When I hooked my phone up and turned the ignition, it started charging. But from the moment I took off, it stopped. I then began testing and found out that when the rpm goes from stationary to around 3 to 4000 it stopped charging. I now am thinking this is because there is an overload that the usb charger just won't allow and therefor it will no longer give electricity. Do you think my hypothesis is correct? If so, what can I do about it? Or if not, what can I do about it? Or you can suggest an entirely different approach aswell.

Thanks in advance!

[JRH]

Can't see why it should stop supplying volts as the revs increase.

If you have a multi meter, check the 12volt supply to the socket is always on.

Also check the earth where you have connected it to the frame, it would be better connecting to the negative on the battery.

Check the USB is not vibrating loose.

[Mr Fro]

Yarp - I'd check the what the bike voltage is when it's revved up too.

The USB thing might have an overload cut out.

[fastbob]

Yarp - I'd check the what the bike voltage is when it's revved up too.

The USB thing might have an overload cut out.

 

I reckon that's probably the case. I've fitted a female socket direct to positive and negative terminals on the battery and I just plug in a cheap charger when I'm stationary. I had wondered about charging with the engine running but decided against it . Sounds like it might not work anyway from what you say but it obviously works in cars . Maybe bikes in general have more primitive charging systems.

[Joeman]

Are you sure it was the fuse box you connected to?

Not the reg/rec?

[Arthemius]

Yeah I'm sure I connected it to the fuse box. It looks like this: http://www.triumphrat.net/memberalbums/data/1309/medium/fusebox_-_no_labels.jpg

And the charger normally is good quality. I bought it from a local store. It also can handle volts from 10 to 18v. Do you think reving the engine can cause a spike that big? Wouldn't it damage other components of the bike aswell in that case?

Anyway, I have seen lots of people charging there phone from their bikes, even when they are riding. I just don't know how they do it then.

[Joeman]

It won't be a spike. More likely the +ve supply you hooked it to isnt a good one.

Best way to get a charger working is to hook up a relay. That way you can take power directly from the battery.

[Arthemius]

And with a relay you mean a simpel on and off switch hidden somewhere?

And hooking it up directly to my battery won't discharge the battery overtime? I'm scared I'll end up with a dead battery far away from home

[JRH]

With the relay you use a circuit that is only live with the ignition on to energise the relay.

People usually use the rear light feed. So the charger is only on when the lights are on.

[2WheelSolo]

It's also possible that you are getting high frequency electrical noise on the circuit - that tends to stop electronic devices from working and is why most 12v power cables for bikes come with some sort of smoothing circuit. I bought a 12v USB hardwiring kit from Amazon (link here) for around £8. I connected it directly to the battery via a relay and inline fuse, with the relay switched from an ignition live. You can get 'three wire' ones that have the relay built in, which I would probably go for if I did it again.

[Stu]

I would start with the basics

get a multimeter and test what power you are getting across the rev range at the battery

then test at the connections you made then come back to us

[Chrissb6]

Far better to connect your charger direct to the battery to get pure D.C and maybe switch the circuit via a relay. It sounds to me that you may of connected the charger to one of the AC circuits on the bike hence the charger cutting out once the engine has started up and the alternator comes into to play.