Spruce up yer kill switch

[xjwmx]

Power to the coil comes from the kill switch, and it's a little bit susceptible to neglect, for its importance and vulnerability.

I have a light wired up as a generator check light and I noticed if I pressed on the kill switch a little, the light would dim, which was fixed by busting open the switch and cleaning the contacts. I was on the way to intermittent power or low voltage to the coil.

If I didn't have that check light, and most people don't, I wouldn't have known anything was up, because it didn't affect any other light.

 

[aldo5468]

Good advice, and clean the contacts in the ignition switch also. Both of these switches are points where dirty contacts raise resistance, thus lowering voltage available at the coil, which these bikes just can't stand, whether points or TCI. I put a relay in the ignition circuit to power the coil directly off the battery, so these switches don't carry full coil current.

 

[pamcopete]

aldo5468,

I used to recommend a relay to power the coil, as you suggest. The problem is that when the battery is low, the relay may not operate, so you don't get any power at all to the coil. The relay may also drop out when the battery voltage goes low when you operate the starter.

So, with the PAMCO, you can connect the coil directly to the battery with a fuse. The PAMCO remains connected to the kill switch. The coil will only draw current when the PAMCO is turned on by the kill switch. Same idea as a relay, but without the relay. The PAMCO itself only draws 10mA. That's just 1/100th of an Amp so there is no drop across the kill switch.

 

[aldo5468]

Pete, you make a very good point - certainly another big advantage to the PAMCO system; no point at all in using a relay with it. This probably is going to make me sound like a living dinosaur: I still run the original TCI, which means no PAMCO / no PMA unless and until the TCI craps out in an unrepairable manner.

I've had the relay in for about a year now and so far no problem dropping the relay when I engage the starter. I usually have the bike on a float charger when it's garaged to keep the battery fully up. Put in new brushes a little over a year ago, replaced all the clips in the fuse holder ("Radio Shack fix"), and cleaned all the electrical connections I could get to in the harness about the same time, shortly after I got the bike - just stuff you have to do to a 30-year old machine to keep it starting and running well. I have a '94 Virago that shares the same issue of marginal electrical power as 650's, so am used to the necessity of keeping everything electrical clean and tight.

 

[pamcopete]

aldo5468,

OK. Looks like you will not have a problem with the relay dropping out. I ran a relay setup like yours on my trusty '78/E for 14 years and never had a problem, except once when it would not start with a low battery. I soon discovered that I had no spark because the relay was dropping out with the reduced voltage on the battery during the start.

 

[xjwmx]

A relay is nothing but a switch you can't clean....