You may recall that I had a problem with the headlight fuse blowing on my CBF250. I put this down to a bad contact in the fusebox. I cleaned it up and all seemed well. But in the darkness of the Scottish winter the problem re-emerged.
I checked for bare wires causing a short but they were all ok. I replaced the fuse and the headlight worked….for a short time. The fuse blew again when I pressed the started button. This gave me a clue as to what might be wrong.
Bikes in the UK have had, for a long time, "always on" headlights - they don't have a on/off switch. This is for safety reasons. For staring the CBF has a microswitch that momentarily switches off the headlight when the starter button is pressed. This will allow all the power of the battery to go to the starter.
I opened the handlebar switch and found something wrong. A wire from the microswitch was trapped under a metal plate. The insulation was burst exposing the wire. This could cause the fuse to blow when the starter was operated.
I taped up the wire and the back of the plate and this has worked thus fair. Here's hoping.
I can't blame Honda for this. About 9 years ago the microswitch stuck and I opened things up to clean it. I must have trapped the wire then.