Electrical issue

Johnnymac · Apr 7, 2012

I'm back again....

I put my Combat on a trickle charge overnight. When I went out to start it today, it didn't start right away.... Usually it is first or second kick. Once I got it going I slowly started reving the bike when I noticed that the headlight wasn't getting brighter with the increasing revs. About a minute later, the warning light came on RED. Now the light will not go off. Is my alternator dead? I put a 20v Multimeter on the two wires coming from the alternator with the engine idling and it was a big zero? Surely is should have read something. It's not outputing AC is it?

pete.v · Apr 7, 2012

Yes, the stator outputs AC and is then converted to DC through the reg/rec unit. You may not get much at ilde. With the meter on the battery (DC mode) terminals, you should see a surge to 14.5 or so when reving.

Johnnymac · Apr 7, 2012

well, I measured the output of the stator in AC.... it went up to about 18 whenit was being reved. IS that about right?

pete.v · Apr 7, 2012

Yes, that seems right. Now what about out from the reg/rec unit at the battery in DC.

Hobot · Apr 7, 2012

If finding way over 15 v into batter terminals then suspect a failed battery. My first clue on my Combat was taking more kicks than expected and too soon afterwards even with lots of kicks to get a mild warm up and easy instant re-start to prove I could take it to work, it never started again until new battery put in, even with the trickle chargers 1.5 amp trying to help out on mere points needs to fire. Home does not allow a running start as I've done plenty of times far away from home with dead battery - usually d/t charger or key left on issue.

Johnnymac · Apr 7, 2012

pvisseriii said:
Yes, that seems right. Now what about out from the reg/rec unit at the battery in DC.

Here is wher it is getting strange. I just installed my center stand yesterday. This morning, nothing I did would let me start it on the centerstand. When I put the centerstand up, it started right up. This is when I had the issue with the Warning light.....

So I'm out there checking things, I start the bike with no kickstand. Put the bike on the side stand, continues to idle. When I put it on the centerstand, as soon as it is fully enagaged and upright, it shuts off..... it doesn't sputter. It literally turns off. There are no wires anywhere near the stand. I have tried this three times and each time I put the bikeon the centerstand, it shuts the bike off. WFT is going on here? This is really weird.

Johnnymac · Apr 7, 2012

Three more attempts.... each time the centerstand is fully engaged, engine turns off. The warning liught still is on. Brake lights work. Engine OFF.

Hobot · Apr 7, 2012

Suspect the iso mount shift is fauling horn wire down low or brake wire higher up or in head steady area, remembering its a Commando at issue, always think to look at opposite areas or another completely different system component messing with ya. My next step would be idle on side stand then tug,jerk,pull, jossle tap loom parts and even kick the Cdo in the nuts sharply to trace a fault~~. After dark dim sparks has helped me more than once.~~

pete.v · Apr 7, 2012

in addition to what hobot said,
Add some ground wiring. Add one to a headsteady bold down from the coil bracket and one to the backside of the timing chest. or at least validate the ones or twos or threes that you have. Never seem to have enough.

Johnnymac · Apr 7, 2012

pvisseriii said:
in addition to what hobot said,
Add some ground wiring. Add one to a headsteady bold down from the coil bracket and one to the backside of the timing chest. or at least validate the ones or twos or threes that you have. Never seem to have enough.

Well,found the culprit for the centerstand issue.... the dunstall rocker covers pierced through the rubber cover on the coil wire when I put it on a center stand.

Now it will stay running on the center stand after I loosened the coil bracket and rotated it.

Now if I could just figure out what happened with the warning light........

pete.v · Apr 7, 2012

This sort of begs the question, how mushy are those iso rubbers and what kind if headsteady are you using. DT type perhaps?

Hobot · Apr 7, 2012

Alrighty then we can rest soundly with mystery solved. Its tricky to place coils so terminal and nuts don't colloid. But I told ya so about thinking oppositely after first reflex don't reveal anything. I love/hate the constant testing my Cdo's provide me. So far time wise the Norton has won, 2/3rd's down time mystery or obvious trauma verses 1/3 riding em.

Ron L · Apr 7, 2012

Now if I could just figure out what happened with the warning light........

It is no doubt the warning light assimilator. It is typical for the warning light to stay on when they fail. They are notoriously fragile. Of course, you have made certain that the voltage across the battery is greater than 12 volts with the engine running?

Johnnymac · Apr 7, 2012

Ron L said:
Now if I could just figure out what happened with the warning light........

Click to expand...

It is no doubt the warning light assimilator. It is typical for the warning light to stay on when they fail. They are notoriously fragile. Of course, you have made certain that the voltage across the battery is greater than 12 volts with the engine running?

I have known for a while that my battery wasn't in the best condition. Days on the trickle charger would never result in a "green Light" on the charger. I'm wondering if the first thing I should swap out is the battery? Is there anyway to test the assimilator?

When I put the multimeter on the battery with it running... the volts don't increase.

Johnnymac · Apr 7, 2012

Do you guys think that since I now know that the coil wire was shorted..... could this have cause the issue with the warning light being permanantely on.? What I mean is.... could this short have blown the assimilator?

L.A.B. · Apr 8, 2012

Johnnymac said:
Do you guys think that since I now know that the coil wire was shorted..... could this have cause the issue with the warning light being permanantely on.? What I mean is.... could this short have blown the assimilator?

Seems unlikely.

gtsun · Apr 8, 2012

Have you been charging the battery out of the bike? My Deltran "smart charger" will not charge if the batt is connected to the bike.

batrider · Apr 8, 2012

My assimilator died when I forgot to mount the spring properly and the body of the assimilator was rubbing against something. The vibration must've caused the fragile nichrome wire "resistor" inside the assimilator to open up.

Was the assimilator hitting those fancy rocker covers too? For a new assimilator (solid state version) see the SS3AW from CoolCat Express. Only $19.95. They now have these in positive ground too for $23.95. I am using the negative ground standard version with two wires reversed.

http://www.coolcatcorp.com/Merchant5/me ... y_Code=OBM

Positive ground version:
http://www.coolcatcorp.com/Merchant5/me ... y_Code=OBM

Johnnymac · Apr 8, 2012

Would a faulty assililator prevent the battery from charging? When I put the meter on the battery and rev it up, the voltage does not increase. Had a look at the assimilator though, there is no spring. It is just hanging there by the wires dangling under the tank.

VintAge · Apr 8, 2012

pvisseriii said:
Now what about out from the reg/rec unit at the battery in DC.

The all-important question.

Ron L said:
It is no doubt the warning light assimilator. It is typical for the warning light to stay on when they fail. They are notoriously fragile. Of course, you have made certain that the voltage across the battery is greater than 12 volts with the engine running?

Asked again, since the question wasn't answered yet, though I would substitute "battery voltage" for "12 volts" just for complete accuracy.

Johnnymac said:
When I put the multimeter on the battery with it running... the volts don't increase.

Answered, sort of. It behooves to know exactly how this test was done and what the actual voltage measurements were before you condemn items out of hand.
1) What is your resting battery voltage? A fully charged battery should show 12.6 volts. Less than 12 volts after a complete charging (and surface charge removal during a light load test) probably indicates a bad battery.
2) If the battery voltage seems good however, what is the reading with the engine running at both idle and say 2500 rpm? If the resting voltage stays the same with the engine running (especially at the higher rpm although, with an alternator, you should see charging at idle), then you're not charging and since you see AC from the alternator you may have a regulator problem. This was where pvisseriii was going originally and I just think you should be sure of your testing.

Electrical issue

Johnnymac

pete.v

Johnnymac

pete.v

Hobot

Johnnymac

Johnnymac

Hobot

pete.v

Johnnymac

pete.v

Hobot

Ron L

Johnnymac

Johnnymac

L.A.B.

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gtsun

batrider

Johnnymac

VintAge

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