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Dim Headlight

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56pan
Posts: 33
Joined: Fri Jul 13, 2007 8:05 am
Bikes: 1956 FLH
1997 FLHTCI
Location: Eighty Four, PA

Dim Headlight

#1

Post by 56pan » Wed Aug 16, 2006 9:10 pm

Description: When my '56 is at idle the headlight is not very bright.

When my '56 is at idle the headlight is not very bright. But when I rev the engine it gets very bright until it goes back to idle. I have converted to 12 volt using a Cycle Electric generator with the regulator attatched at the end. It is the standard regulator, not low input. Any help? Thanks.
Bill



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Re: Dim Headlight

#2

Post by 108 » Thu Aug 17, 2006 12:18 am

56pan, You should have about 12.5 volts or more at the battery with everything turned off. If its near dead or has a bad cell. the voltage may just be going too low at idle. Also in the opposite direction, if voltage at the battery in going over 14.5 or so when you rev it up , it may be flareing up from too much voltage. I've also seen dim lights from custom wireing that was too small a guage . Voltage at the bulb terminals should only be a few tenths of a volt less than at the battery.

56pan
Posts: 33
Joined: Fri Jul 13, 2007 8:05 am
Bikes: 1956 FLH
1997 FLHTCI
Location: Eighty Four, PA

Re: Dim Headlight

#3

Post by 56pan » Thu Aug 17, 2006 9:28 pm

With the bike running I have 12.5 at the battery. I have 10.5 at the headlight at idle and 14 volts at rev at the headlight. Also, when I turn the ignition on the headlight is out. When I start the bike the light is on. And at idle the generator light is on dim But when I turn the ignition switch to lights the headlight stays on, tail light comes on and dash lights come on and the generator light goes out. Even at idle. Figure that one. Thanks.
Bill

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Re: Dim Headlight

#4

Post by Panacea » Fri Aug 18, 2006 1:57 am

Do you have a jumper between the ignition terminal and the lights terminal on the ignition swith by chance? Or some other way for power to back feed thru the switch?..MW

PanPal
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Re: Dim Headlight

#5

Post by PanPal » Wed Aug 23, 2006 4:07 pm

What is the voltage on the battery with the bike not running?
My battery died (6 volt) and the bike would not start. No headlights with the switch on. I was in a Wall-mart parking lot and went and bought a 6 volt light battery . A very small battery from the camping section and a pair of jumper wires. I jumped the little battery to my dead battery and turned the switch on. My gen and oil light on my dash lit up, but if I turned my headlights on there was nothing. The bike fired up first kick and lights were strong running off the generator through a cooked battery. But they would dim at low idle as with yours.

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Re: Dim Headlight

#6

Post by Kuda » Wed Aug 23, 2006 6:21 pm

You're runnin' on borrowed time PanPal! If you haven't already, make sure you replace that battery with a fully charged one soon. Running a dead battery is seriously hard on a generator/regulator, and it'll kill one or both fairly soon...

-Kuda

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Re: Dim Headlight

#7

Post by PanPal » Wed Aug 23, 2006 9:12 pm

I have a new battery now. I only rode a few miles and it didn't run perfect but it did get me to a shop with the correct 6 volt battery. I was in Kentucky at the time and would not recommend this as a long term repair but it was better than pushing at the time. What actually happens to cause damage to the generator or regulator? Does this also happen with a mag and no battery?
56pan says he has no light until the bike is started. I had the same deal with the dead battery.

56pan
Posts: 33
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1997 FLHTCI
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Re: Dim Headlight

#8

Post by 56pan » Wed Aug 23, 2006 9:34 pm

You misunderstood PanPal or I didn't explain clear enough. I have a 12 volt system. I turn the ignition to on. There is no lights on because there isn't suppose to be unless I turn the ignition 1 more click to "light on" position. The lights work with ignition in "lights on" position. Nice and bright. Battery is good. Now, I have ignition turned to "ON" position with no lights and start the bike the headlight comes on automaticly. Not the tail light. Tail light will come on when I switch to "Lights On" position. At idle with ignition in "ON" position the generator light will come on lightly. Flickering. But, I turn to "Lights On" position the generator light stays off at idle. Real head scratcher. Thanks.
Bill

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Re: Dim Headlight

#9

Post by Kuda » Thu Aug 24, 2006 11:59 am

"What actually happens to cause damage to the generator or regulator?"

Simply put, they overheat. The gen isn't strong enough to charge a dead/weak battery and will overheat.

"Does this also happen with a mag and no battery?"

Nope, unless you're running waaaay too many lights....

"56pan says he has no light until the bike is started. I had the same deal with the dead battery."

Different situation. He's probably got a short somewhere. Your bike just didn't have enough juice to light the headlight until it was running.

"Now, I have ignition turned to ON position with no lights and start the bike the headlight comes on automaticly. Not the tail light."
Is it by any chance your high beam that comes on without the switch being turned to lights? That could be an internal short in the headlight bucket or at the hi/lo switch. If you've got stock or near stock wiring, check your wires near the distribution panel and near the ignition switch. You've likely got a short that's powering the headlight without the switch on.
"At idle with ignition in ON position the generator light will come on lightly. Flickering."
Yep, it's almost certainly a short, just a question of tracking it down. Start with the panel, ignition switch, and if you don't find it there start with the headlight ground wire and back track to the bulb, then back to the switch. It could be backfeeding through the ground wire, not good... Good luck!

-Kuda

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Re: Dim Headlight

#10

Post by fourthgear » Thu Aug 24, 2006 12:15 pm

56pan
As kuda says and try cleaning your ign. switch contacts, there is a thread on it a while back , you would be surprised how dirty contacts Will change voltage readings. Thats if you have a stock type switch , not sure how some after market switches are made . I have the newer electronic type and you would not believe the diff. on switching. Very smooth operation and no hesitation on switching from ign. only to lights and ign.

nickpipe
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Re: Dim Headlight

#11

Post by nickpipe » Sun Aug 27, 2006 11:28 pm

Here is a simple explanation of what the regulator does on your pan, reguardless of weather it is 6 or 12V. Think of the regulator as a valve on the end of a 1/2 inch pipe that is connected to a pump( your generator) With the valve closed the pump puts pressure(Voltage) in the line. The faucet( Regulator) allows a certain amount of water( Current in Amps) to pass depending on load. As the faucet is opened ( current load increased) The pump is able to keep up as long as the demand factor ( capasity of the generator) isn't surpassed. The pressure will stay the same ( 12-6VDC). As the load increases the capasity of the pump(generator) is surpassed ans pressure(Voltage )begins to drop. The regulator also has a working capasity and if surpassed for long enough, unlike water through a pipe electrisity has to deal with resistance to flow and the result to resistance is heat. if the heat is great enough for long enough it burns the components of the regulator out and stops regulating flow. The battery in the system is like the expansion tank on a water pump. it stores unused power till needed and once full the regulator eases charging by regulating the field current in the generator andoutput is slowed. If the battery is dead or has bad cells the regulator never fills the battery and will eventualy die trying.
56 pan if you have 12+volta at the battery and only 10+ volts at the headlight you have a serious resistance between the battery and the light. More than likely the Ignition switch, or even a short in your wiring. I have changed the wiring on my bikes and now run a wire directly from the battery through a relay to the headlight. The ignition switch controls the relay and the whole system runs as normal minus the resistance the switch is notorious for.
Just my 2 Cents worth
Nick

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