Blowing head light bulbs

[Gareth123]

My bike has started blowing it's head light bulb but only when I'm revving the engine. My brother reckons my stator coil is stuffed as he put the multi meter across it and came to that conclusion. Its only putting out voltage on 1 of the phases apparently. (I'm an electrical dummy. I can change a light bulb but that's about it.)

Any suggestions for what I should check and how I should go about checking it? Please make the answers as simple as possible.

[CookMySock]

If he knows his stuff, it is quite likely he's right, but I'd be surprised to see it blow only headlamp bulbs (and nothing else) running on one phase. In fact, if it was a three phase floating system I'd say that was impossible.


Steve

[Gareth123]

If he knows his stuff, it is quite likely he's right, but I'd be surprised to see it blow only headlamp bulbs (and nothing else) running on one phase. In fact, if it was a three phase floating system I'd say that was impossible.


Steve

I watched him test it and he did test 3 wires so I'd assume it is a 3 phase system. This must mean I have a separate problem thats causing the bulb to blow right?

[neels]

What bike is this on? A wiring diagram would be useful to narrow down what it might be.

[Spuds1234]

Good luck finding a manual for this bike. Its like the bike doesnt exist online.

2 of the phases short to earth and one seems fine as its putting out about 55v. The battery voltage doesnt increase when the bike is rev'ed so Im guessing that the stator coil is fucked.

[CookMySock]

2 of the phases short to earth and one seems fine as its putting out about 55v. The battery voltage doesnt increase when the bike is rev'ed so Im guessing that the stator coil is fucked.Rewind time - it's not expensive.

That shouldn't make the bike blow headlamp bulbs though.

Steve

[Spuds1234]

The bulb holder for the head lamp was dodgy so thats been fixed now and should be sweet.

Im still trying to get him to go over the bike's electrics with a fine tooth comb and check all the connections and make sure they are clean and there are no shorts or broken wires.

[davereid]

Rewind time - it's not expensive.

That shouldn't make the bike blow headlamp bulbs though.

Steve

I had an xj650 that used to blow headlight bulbs at high rpm. It usually waited until I was passing a truck in the dark.

It was caused by a vibration from the front mudguard. I could actually feel it "buzz" at some revs. I chopped 2" off the front and back of the mudguard and problem solved.

Of course, at the time I was an electrical apprentice. I therefore fucked around for ages trying to find an electrical fault that wasnt there. Even though I could feel the buzz, I was determined to fix the electrics electrically.

[Gareth123]

I had an xj650 that used to blow headlight bulbs at high rpm. It usually waited until I was passing a truck in the dark.

It was caused by a vibration from the front mudguard. I could actually feel it "buzz" at some revs. I chopped 2" off the front and back of the mudguard and problem solved.

Of course, at the time I was an electrical apprentice. I therefore fucked around for ages trying to find an electrical fault that wasnt there. Even though I could feel the buzz, I was determined to fix the electrics electrically.

My front mud guard does have a bit of a rattle. Its got a crack in it which wouldn't be helping. Gonna go over the wiring loom when I get a chance. will start chopping parts off as a last resort.

[MotoKuzzi]

The bulb holder for the head lamp was dodgy so thats been fixed now and should be sweet.

Im still trying to get him to go over the bike's electrics with a fine tooth comb and check all the connections and make sure they are clean and there are no shorts or broken wires.

I had a similar problem with my California blowing headlight circuit fuses randomly. I pulled the headlight apart and found a metal clip floating around inside which must have vibrated / bounced up across the spade terminals every now and then causing a short. Problem seems to have gone now.

[davereid]

I pulled the headlight apart and found a metal clip floating around inside which must have vibrated / bounced up across the spade terminals every now and then causing a short..

Thats a normal factory option on Italian Bikes, the random short circuit.

Mind you, my BMW has one of those lurking, I just haven't been able to find it. I'm glad its my bike not a customers, I have spent many miserable moments stopped on the side of the road after "fixing" it !