Cool 01 back story and related questions.

[matt glascock]

So, this ultrasweet 01 Squirt I've been shamelessly bragging about recently came with a top-secret bonus. Its plated! Off-road only head tag and all. I have the title and last registration in hand. Amazing. It was a gift from a local dirt bike speed shop legend to his daughter who in turn sold it to me forty years after its last registration. He fixed it up for her with a lighting system, a useless mirror, and a squeeze bulb (surprisingly loud) horn. I'm guessing after a bit of midnight porting and a fresh bore/piston for some dude down at the court house, PRESTO - plates. Totally non-kosher. As I'm describing this, I'm wondering if sharing this info on the forum is such a good idea. What the hell - onward. It has a Triumph tail light/brake light. The headlight I'm not sure about. The bright indicator is on the top of the bucket. Oh, none of it works currently (good one, huh?) so now the questions:

No spark until I unplugged a plastic multilead connector under the seat. I'm of the mind to start from scratch ala DS trail lighting kit schematic. Questions: Can I just tee into the headlight hot lead to the front brake spring switch then back to the brake light without effecting headlight brightness when I hit the brakes? Similarly, Can I tee into the rear running light hot through the rear brake pedal spring switch to the brake light? If my recollection of physics serves, these should both constitute short parallel circuits so there shouldn't be any voltage drop. Also, where would the best position be for adding a voltage regulator to the harness. This is a direct lighting system. I don't want to dig into it using my usual M.O. - not really slowing down but still half-fast. More to come. Thanks all.

[viclioce]

Pictures. We need pictures. No pictures, no bike! LOL!!! Come on Matt. Quit teasing us!!! Victor

[matt glascock]

I will get some together

[Dale]

Matt,
Assuming there is no battery, then you can connect a regulator between the lead carrying the AC voltage and ground. Locate that AC wire under the seat and tie into it. Your frame might already have the mounting tab under the tank for the regulator. I don't recall on the 02 frame.
If your lamps are 6vdc and you use a 6 volt regulator then I doubt that there will be much dimming due to RPM or braking. If the bulbs and regulator are 12 volt then you will probably get some dimming.
Dale

[matt glascock]

Great Dale. Thanks! That's just what I was hoping to learn. You are correct - direct system off the mag and all 6 volt lamps. Even without the battery, do I need to fuse the circuit?

[Dale]

Fuse?
No, not necessary. On the street legal models only the DC circuit is fused.

[viclioce]

Fusing the circuit is easy enough to do, and, with a 5 amp fuse, you’ll blow the fuse before you’ll blow the headlight. I’ve switched all my bikes over to 5 amp mini-blade fuses. Easy to carry spares in the tool box. Easy to change in a pinch! Victor

[Dale]

There is no battery in the circuit. If the AC power lead gets grounded then it is just shunted to ground. Nothing burns up. There is zero current.
It is the regulator that protects the bulb in this AC circuit.

[matt glascock]

Thanks fellas. Great info Dale. If I'm reading you right, any point on the AC hot lead between the magneto and secondary coil will do for VR positioning?

[Dale]

Thanks fellas. Great info Dale. If I'm reading you right, any point on the AC hot lead between the magneto and secondary coil will do for VR positioning?

The AC hot lead will be the from the lighting coils. This is a separate circuit from the ignition source (exciting) coil which feeds the secondary coil.
Since the 01 Dirt Squirt has the same wiring harness as the 99 Road Toad, I would assume that the AC hot lead will be the Green wire at the plug under the seat. Confirm that your lighting is connected to this green wire and then tie the VR into this circuit (The VR is connected between the hot lead and frame ground).

[viclioce]

So Dale. Are you saying that if there’s no battery, there’s no need to protect the wiring circuit with a fuse? Is it not possible for the lighting coil to to produce more than 5 amps of current in high rev situations? That would be interesting in deed. Victor.

[Dale]

So Dale. Are you saying that if there’s no battery, there’s no need to protect the wiring circuit with a fuse? Is it not possible for the lighting coil to to produce more than 5 amps of current in high rev situations? That would be interesting in deed. Victor.

Yes, that is what I am saying. One has to understand the difference between the DC circuit that is connected to the battery and the AC circuit driven only from the magneto. Overload/short the battery circuit and you get current draw that will blow a fuse.
If the magneto driven AC circuit gets shorted, you get nothing. Both sides of the lighting coil would be at ground.
Study the wiring diagrams. The engineers that designed these bikes did not place a fuse in the AC circuit. So I feel confident to say none is needed. If one wants to add one, that's fine. Just not needed.

[viclioce]

Great to know, Dale. Thanks for the answers. Always wondered why there was no fuse needed when just running the exciter coil! Now I know! Victor

[matt glascock]

Thank you Dale. That's just what I needed to know. Interestingly, there are about a million dead-ended wires in the headlight bucket. I'm starting to wonder if the previous owner retrofitted a Road Toad harness and there are turn signal leads, etc. included. This is going to require a bit of sorting, but the dope you provided regarding the hot tie in point is gold. Thank you.

[viclioce]

Matt. If there are pink, grey, and light green in the bucket, then it’s definitely a harness for taking turn signals! Victor

[matt glascock]

I'm going to check it out, Victor. Unfortunately, it was the estate sale of the man who built the bike for his daughter where I got the bike. He's gone.