81 Ironhead Electrical Problem

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Apr 7, 2008 | 05:35 AM

nicksorg

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81 Ironhead Electrical Problem

Hi guys. Now that spring is here in New England, last week I took the bike out for a short ride. On Saturday I took it out again and it died at the end of my street. It wouldn't start, no lights, etc. I'm going to test the battery tonight and see if itis charged. I'm also going to pickup a starter relay as I've had to replace them in the past. Can someone give me steps to test the relay? Mine has 5 blade plugs.
Thanks
Nick

Apr 7, 2008 | 01:12 PM

piniongear

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From: Houston Texas

RE: 81 Ironhead Electrical Problem

What year model is it?
Does the starter turn over (spin)? If yes, forget the relay....it works.
If your battery died then the starter will not turn over of course. And why did it die?
A little more info is needed for someone to help you.
If the bike is newer than 1974 I will have to leave it to another member to give you some tips.....pg

Apr 7, 2008 | 01:29 PM

supr2nr

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From: West Tennessee

RE: 81 Ironhead Electrical Problem

PG is right. Did the bike's motor just stop running at the end of the street or did it stop running and loose all power to everything? If it just mysteriously lost power to everything it's likely a ground issue. Meaning the chasis ground could have come loose or the cable could have broken.

Check the obvious first. If the bike has power (the lights come on) but the motor does not crank or turn over at all when trying to start it then it might be a starter relay or a short in the starter circuitry.

One time on my bike I clamped the handlebar controls down to much and it cut the starter button wire enough to touch the metal on the bikes handlebar and short out everything. It would trip the circuit breaker and then lights wouldn't come on and it wouldn't turn over at all.

Apr 7, 2008 | 09:11 PM

nemesistech

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RE: 81 Ironhead Electrical Problem

These problems are fairly easy to figure out with only a test light. If you dont have a wiring diagram, trace voltage back from the battery and see where you lost it., check grounds.

Apr 8, 2008 | 07:15 AM

nicksorg

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RE: 81 Ironhead Electrical Problem

Thanks guys. It totally died on me at the end of the street - engine, lights. I put the battery on the tender last night and checked that its charged this morning. I turned the key on and nothing - no headlight. I'll start tracing it tonight.
Nick

Apr 10, 2008 | 01:23 PM

nicksorg

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RE: 81 Ironhead Electrical Problem

I started checking wires and moving them around.It looks like there it is a problem with the negative battery cable. Wiggling the wires around it got the lights on again and when I hit the starter button, it shorted out. I'm going to pickup a new set of battery cables tonight and go from there. Once I disconnect & reconnect the battery, do I need to polarize the generator?
Thanks
Nick

Apr 10, 2008 | 11:11 PM

piniongear

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From: Houston Texas

RE: 81 Ironhead Electrical Problem

Most likely there is nothing wrong with the ground cable itself, but rather a bad and dirty connection.
Remove the cable at the (-) Batt post and clean the battery post with some stainless steel wool.
Do likewise for the barrel of the cable end. Once they are clean, apply a light coating of grease to the post and tighten down secure. I bet everything will be fine after that is done........pg