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Hi,
I have just installed a phone mount with wirless/USB charging facilities and currently have it wired directly to the battery as per instructions.
Not really what I want, as I would prefer this to go onto a live feed after the ignition switch so when the bike is off, the charger is off... (I will forget and drain the battery!) I also noticed that the heated handles are also directly wired to the battery and even though it has a 'battery save' mode, it just doesn't seem right. In that case however I would expect that I need a relay due to the large current involved...
I do have a wiring diagram, however does anyone know a good point to tap into the wiring without having to pull the whole loom apart?
Thanks,

JDS
 

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try black/red wire coming out of ignition switch. It's only powered when key is in ON position. Verify:

1. trace wiring bundle from ignition switch to where it connects to main harness

2. back-probe connector where black/red wire goes in to measure voltage

3. measure voltage with key OFF, voltage = ??

4. measure voltage with key ON, voltage = ??
 

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also DO NOT use crimps or vampire-tap to connect to that black/red wire!!! That's main power-feed for EVERYTHING on your bike. Crimps and taps risk cutting that wire and NOTHING will work if damaged. Use properly tied and soldered connection only!

 

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For heated grips, due to power needed, it should have main feed come from battery. And as you mentioned, use relay to turn power-line from battery on & off. Use black/red line from ignition-switch to control relay.
 

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The other option, if you don't want to go hacking into the ignition loom is tap into the power feed for the headlight from the fuse box near the battery, then use this to trigger the relay.

You would actually also be surprised how little power heated grips draw. I have mine wired straight off the headlight fuse circuit, however I do have a hid in the headlight which draws less than 2a, even on a cold start (I measured it before I wired the heated grips into that circuit, which is the only reason I did it). It work well as it turns off with the key (obviously) and the grips turn off without having to manually shut them down or risk the timer not cutting them out (mine doesn't have a timer that I'm aware of). I can't remember the draw of the heated grips (can't even remember the brand now), but it was definitely less than 10a as that's all the headlight circuit is rated to and that's as high as my multimeter goes for a direct amp draw measurement.

As for usb power, I recently fitted a usb/cigarette socket to the handlebars on my sv650. I was thinking the same as you about isolating it from the battery, but measured the standby draw (with no devices connected) and it was about 0.01a on my multimeter. I'm not worried about that much parasitic draw, so wired it straight to the battery (it had ring terminals fitted to the wiring loom already) and I haven't had any issues even sitting for a week or more without being ridden. Although that has a bigger battery than my cbr, if you're riding every day or few days I can't see it being an issue.

I've also got a usb socket under the passenger seat on the cbr, which I originally had wired straight to the battery, bit forgot about it for probably 6 months and killed the factory battery (only on the second battery since new, 2011 model) so I rewired that off the headlight circuit too as it would be very doubtful that I'd be using that and the heated grips at the same time, plus it only draws power when it is being used to charge something. The thing that ran the battery down I think was the small led light on the front of it to show when it was being supplied power. I am considering getting another handlebar mounted one for the cbr too as it is really cumbersome to cram a phone under the rear seat to charge and the end up getting dirt and stuff on them just through normal riding...
 

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also DO NOT use crimps or vampire-tap to connect to that black/red wire!!! That's main power-feed for EVERYTHING on your bike. Crimps and taps risk cutting that wire and NOTHING will work if damaged. Use properly tied and soldered connection only!

great one
 
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