XT550 no headlight, signals, or horn

[Zuminazx]

I just got my XT550 back on the road today, however none of the essential bits to pass inspection are working. The headlight is very, very dim and the taillight flickers. The blinkers don't blink, rather slowly turn on and remain on. I know the battery is dead (left out in the cold all winter) and probable won't charge, but I thought these bikes have capacitors and don't need batteries? I'm afraid it might be the voltage reg or worse. Anyone know where to start?

[Wabbit16]

When I got my xt it had the same probs. The battery acts like a cap, and prevents the reg from overworking. If yours is like mine, the headlight brightens if you use the horn and it's bright at idle but dim when revving it. Replace the battery, and see if the problems go away. Running with a crapped out batt will ruin the reg/rec very fast

[Zuminazx]

The light doesn't get brighter nor does the horn work at any time. I have a protection plan on the battery so I guess I'll try a new one firt before I start shelling out the big bucks for a new reg. I was under the impression that the battery was just there for show considering it's the size or a deck of cards.

[Wabbit16]

My battery's kinda big. 4ah IIRC. Not big as in biiiig but about 4" x 3" x 4". Maybe an electrician could chime in and help you since I don't know squat about that stuff.

[D.T.]

You will have to see how many volts are across the battery with a DVM. Should be around 12.2 VDC when key is off. When running you should have around 13.5VDC and around 14 VDC when revving the bike.

I had a burnt connector behind the headlight to the ignition switch once this may be something to look for. Could be some wires smashed together on the supply side or a short to ground.

I also have the White Brothers battery eliminator on my XT. Just a big electroylitic capacitor. No reason carrying a huge battery around if I have to kick start the damn thing. I don't need to bring it to pass any inspections either. It is plated too and I removed the horn. I'd rather shake my fist at someone than honk the horn.

[Wabbit16]

I, OTOH, would much rather throw boulders or batteries or furry dingleberries than shake my fist. With my luck I'd dislocate my shoulder or something whilst doing it...

[Smacaroni]

I must admit, you've got some luck over there.

Stick a battery in it first.

After that, your rect/reg is likely fried. I'm working on an inexpensive ($30) circuit to fix a bad rect/reg on a single phase bike like the XT550. Same circuit would probably work on a three phase, but will be about $38 instead of $30.

If you're sure your rect/reg is fried, shoot me a PM and I'll send you my diagram.

A possible cheap solution is to put a large diode on one side of the alternator output, it will cost about $2 and if it works the downfall is only half the power from the alternator is usable, but it's cheap and worth a shot to pass inspection. You'll still need a battery though.