To the electrically minded

check the boots that hook to the plug, I found a couple of bad connections in mine, cut the wires back and installed new connectors and boots, you can get them at most part stores that have some racing items, it cured the intermittant problem

So last night my starter solenoid quit. Totally crapped out.

Got a replacement on the way, but since the main generator output connects through the solenoid, could a leaky solenoid cause some of these issues? When I look out the solenoid and started the bike by touching the two wires, the biek was able to rev without flickering the neutral light. I know the solenoid doesn't share any circuits, but could there have been crosstalk between the push button and the starter line?

It's possible there is something in the solenoid causing it to ground through the starter. It's not a direct short, but the starter can take so much current that it seems like a short to the charging system.

I say take it apart and see if the contact plunger started crumbling or see if there is some loose metal in there.

On bike last night, I got 12V to the supply side of the solenoid, but 0 V to the starter side when the starter relay was engaged. What was weird, is it was "clicking". When I took it off it was reading about 3 Mohms across the starter terminals just as is off the bike. I took it apart, and saw nothing really weird that would have explained the suddenly failure.

However, while I was dismantling, I did break the connection from one of the switch lines to the solenoid coil, so a replacement was now mandatory.

The only thing of note was the copper bar attached to to the solenoid plunger had deep marks on it from where it was contacting the terminals, but with the amperage load going through it, I would have expected that.

I'm not optimistic that this is the last issue as I'm still blowing the 10AMP brown subcuircuit fuse about once a week. Since this is so infrequent and not consistently reproducable, I'm having trouble thinking of a way to find the bad part/wire. The brake lights (switched) run of this circuit, so I can't run around town with the fuse out too easily or with it disconnected.

Any ideas on how I can vet out each part on this circuit without putting myself in danger?

Post edited by: dnpurdy, at: 2007/07/05 11:15

hate to say this, you may need to use the good ole Ford Wiggle test to find the bad wire

Boy, I can't wait to see how this all shakes out in the end. This thread has been the most informative thing I've read for years. Yes, I know, I should get out more.

I'd class myself as an "accomplished amateur" in electrical stuff so my "e-consciousness" has been raised several levels just reading this thread.
I have to say that you guys are certainly persistent and I offer a big tip of my helmet for your "stick-to-iteveness". Please don't quit now.

Well, i'm rapidly getting to the point that the problem will fix itself as I keep replacing parts in the system!! My new starter solenoid should be here shortly.

Post edited by: dnpurdy, at: 2007/07/09 18:21

The saga comes full circle.

THe bike has been running alright, but I can tell it's running between 12.4 at idle and 13.5 at top, not maxing out like it should. So I decided to check out the amp situation. I grabbed my current probe after riding 20 minutes at 4000 rpms on the highway. Out to circuits -8 amps, in to battery +10 at 2000 rpm. As I revved, the amps just went up linearly.

Clearly the batt can't be right. Going to go out now, pull it, and put it on the slow battery tender charger overnight, then use hydrometer in morning when done.

Any other things that could cause that? The amp draw off the main fuse wire didn't go up after revving and after 3000 went down ( I assume due to dwell not keeping up fully anymore). So it isn't a load after the main fuse. But due to the placement of the main fuse in the circuit, that leaves only the battery, right?

FOUND THE LAST ISSUE

Take a look -- www.davidpurdy.net/Wire.png

This was my replacement wire from regulator to battery and this had recently happened. Clearly the amps were being generated but not getting to the battery.

Finally done - whew

Has this all been for real?

That's some nasty corrosion you've got happening there.
Glad to hear it's all sorted. Again, a tip of my helmet to you and loudhvx for your persistence. What a saga !!!

Has this all been for real?

Hey, nads.com, do you think ANYONE could make this stuff up ?? :laugh: :laugh: :laugh:
Ahhhh.....the perils of owning old bikes..... :laugh:

dnpurdy wrote:

Well, lack of sense wire should only have the affect of over charging. A disconnected sense wire means the regulator never switches the SCRs on to shunt to ground. The only effect that would produce undercharge with the sense wire is if I have a sense to ground short.

Hmm...interesting thought there. Sense wire is after the 30AMP main fuse, but before the bus of 10AMP subcircuit fuses. If I'm getting a small short to ground along the sense line, that could eat up wattage without necessarily pulling the 30 AMP fuse.

Also, could my ignition switch just be heating up? Could that be my "bad connector"?

I was thinking the ignition switch may be a cause ,also. But I was going to suggest running a switch to your low-beam lamp. My '78 650 C2 has one and that seems to help my charging issues @ Idle. I have an H4 bulb. The headlight is no effectively controlled by the highbeam switch.

By the Way , this is one of the best threads I've ever seen here, keep it up:)