Intermittent Wiring Fault

I have been chasing an intermittent wiring fault that results in loss of spark. Yesterday, I finally took the stock rubber connector block apart and threw it away. I discovered that despite the fact that it looked decent, that time and fatigue (vibration?) had caused most of the internal contectors to split lengthwise. When the wires were removed, pieces of metal just fell out. This part of the tale is pretty well documented in other threads here, but if you still have the stock piece and are fooling yourself that it is fine...be wary.

Sadly, despite this, I still have a break or fault somewhere. So I have a few questions. I have read references to a ballast resistor bypass wire. Is this on the electric start models only? If not, can someone help me identify it and how it is supposed to be wired?

Second, it would appear that the entire circuit goes through the switch cluster on the handle bars for the kill switch. So I am assuming that the switch breaks the circuit to kill the engine rather than grounding it out. This seems a perfect set up for intermittent failure! If this is correct, has anybody successfully wired their kill switch so that it isn't in the middle of a very necessary circuit? I have to admit, my brain struggles to transfer some basic wiring ideas to postive ground.

As always, any enlightenment will be enjoyed and put to direct service.

rvich said:

I have read references ballast resistor bypass wire. Is this on the electric start models only?

Click to expand...

Yes.

rvich said:

it would appear that the entire circuit goes through the switch cluster on the handle bars for the kill switch. So I am assuming that the switch breaks the circuit to kill the engine rather than grounding it out.

Click to expand...

Correct.

It seems as though it should be possible to use a normally open switch that would "ground out" the coils, thus eliminating the spark. If this were wired from the frame (ground) to between the ballast resitor and the coils the resistor would eliminate the direct circuit to the battery and it would disable the coils...right? Or do I have my basic DC theory so goofed up that I will just melt something down or acheive other undesired effects?

rvich said:

It seems as though it should be possible to use a normally open switch that would "ground out" the coils, thus eliminating the spark. If this were wired from the frame (ground) to between the ballast resitor and the coils the resistor would eliminate the direct circuit to the battery and it would disable the coils...right? Or do I have my basic DC theory so goofed up that I will just melt something down or acheive other undesired effects?

Click to expand...

You are correct, that would work and considering it would not be "on" for a very long time, no harm would be done to the ballast, you just have to make sure the fuse would not blow with the added load.

Jean

Why not just fix the original switch, if that is the problem?

The switch contacts probably need cleaning?

The ignition switch contacts would probably benefit from a clean-up too?

Second, it would appear that the entire circuit goes through the switch cluster on the handle bars for the kill switch. So I am assuming that the switch breaks the circuit to kill the engine rather than grounding it out. This seems a perfect set up for intermittent failure! If this is correct, has anybody successfully wired their kill switch so that it isn't in the middle of a very necessary circuit?

Click to expand...

You can put a relay in the circuit and use the kill button to trigger the relay. In this manner you are only relying on a small current to be passed from the kill button. I have done this several times.

Fix the original? What an idea! I guess I have enough issues to deal with that there is no need to reinvent the wheel. Yet anyway. I spent most of the afternoon goofing around with the bike. I cleaned the kill switch as well as improved the contact for the ground wires between the engine and the frame. I should admit that I had not gotten switch housing apart prior to today as the screws were just buggered enough to prevent a decent bite. But finally rounding up a small philips bit for my impact driver I easily broke loose the offensive screws. The housing was full of what looked like gelatinous brake fluid! Ouch! OK, so a leaking master cylinder might be at fault. The thing is kinda wet, but fixing the brakes is secondary to getting things to run...right?

I finally got the oil level screw out of the primary today and drained about two quarts of oil out of it. I have no idea if it was put in there by the previous owner. Or if it leaked in there. Considering that the bike has sat for so long, having the entire crankcase wet sumped and the primary flooded might be a good thing. Getting this drained enabled me to adjust the timing with a light as previous attempts saw oil splashing out of the timing port all over the exhaust.

As I have said in a different thread this bike sat idle for almost 20 years. So there are lots of small issues to deal with. Many of which will be the result of rotting rubber. It is funny though, the exhaust was still polished and silver until I started working on things and by now it has turned light blue and straw. So it makes me wonder if the previous owner just gave up on solving some of this stuff as it sure seems that the exhaust would have colored up prior to this.

I did get to go for a ride. There are vibrations and all sorts of things that will need attention as I move forward, but it is a good thing that we are past bug season...otherwise I would have a bunch of em stuck in my teeth today. And hey, the lights worked!