Electrics problem

[alexransome]

Hi There,

Twice in a row I've gone to my bike and found it flat. Twice I've ridden it for an hour in London traffic to charge the battery. Tonight when I took the seat of and smelt the battery I could smell that melting smell ... The battery looked OK so I took off the fuse lid and saw it ... the 15 amp fuse had melted. Not just blown but melted. I took it and the bike started, i did a lights check and they all work I checked the rest of the lights and noticed that the rev counter and neutral light were no longer working. Does this sound right? And what would cause the fuse to melt in the first place?

Thanks

[alexransome]

I have an update ...



Last night I turned all the switches to off, even flicked the engine cut off to 'off' and got up this morning 30 mins earlier so I could wait for someone to give me a bump start ...



Well I got work, checked the voltage, it's 12v without engine running and 14v with the engine running.



If the fuse was causing a short then would this have stopped the battery from charging last night, but as it was removed last night, would the battery have been able to be charged up during my 50min ride to work this morning?

[m40man]

Your ride to work will certainly have given the battery a boost. At least you know your rectifier seems alright . You could do with trying to isolate whatever short you have with a multimeter. (If switching everything off sorted the problem, then I guess you can't afford to experiment each night by switching off specific things, in case you find the problem & can't get to work .)

[alexransome]

I've just been outside to try and get a better idea of what's going on.

I've noticed that using a spare 15amp fuse the rev counter and neutral light come back on, but after revving it up to about 7000rpm and then checking the spare fuse it was hot to touch. If I'd have left it longer it would have melted ... again. I've tried to trace the cable but have have lost it in the tape that's wrapped around it and right now am not able to got that far ...

The melted side (I'll assume this is the + side) is a brown and blue cablle the other is brown but with a yellow mark on it, does anyone know where these go. I may have it the wrong way around, but the combined coulours are correct.

I do have a Haynes at home, but that's no good to me right now