Voltage Drop

Mr-Bojangles · New Member Joined: Jul 29, 2006 Posts: 9

Okay so here's the deal...my 79 Special is getting a huge voltage drop.

I test my battery before I turn the switch on... it reads 11.04 V. I realize that this is too low to begin with anyway. But once I switch on the key, the voltage drops big time, the numbers go way down to 8-7 V's..

I tested by pulling off connectors and fuses but the voltage still drops. I can get the bike started and it will charge at 14.5 at 3,000 rpm. But, I don't understand what is going on with the massive voltage drop.

I replaced the plugs, plug wires, regulator & rectifier. I cleaned the ignition switch, the kill switch is in good shape.

Any ideas anyone?

xsjohn · Posted: July 22, 2007, 8:33 pm Post subject: Re: Voltage Drop

Bad cell maybe......

John

jayel · Posted: July 22, 2007, 8:34 pm Post subject: Re: Voltage Drop

unplug the coils and see what the voltage drop is

Mr-Bojangles · New Member Joined: Jul 29, 2006 Posts: 9

Well I just tested the battery... it's sitting at 11.98 +/- 0.02 volts... I turn the key not much drop... and had no problems kickstarting. I removed the electric start because I'd like to hardtail the bike sometime this year and go with just the kick. Electrical can be such a pain.

Thanks guys for the tips.

Now I just have to fix the high rpm's and my guess it's just a matter of cleaning out those carbs. I replaced the auto advance springs and that helped a bit. But my bike is idling poorly. So the next step is to give those carbs a surgical cleaning.

jayel · Posted: July 22, 2007, 9:39 pm Post subject: Re: Voltage Drop

does the advance return smoothly? you may need to pull and grease the seals and bearings the advance rod runs in

Mr-Bojangles · New Member Joined: Jul 29, 2006 Posts: 9

It does return smoothly jayel. I greased it yesterday and so far so good. The bike is now starting up and charging good. Now it's idling off and on. I know it's the carbs. I ran out of carb cleaner so I've gotta hold off till tomorrow. I hope I can get this bike running finally... It's been sitting for over a year now and I only recently put everything back together.

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