Headlight keeps recharging below 14.5

[xs650custombuildzz]

i got a 1981 xs650 that has a strong headlight. I found out couple weeks ago that when the headlight isnt plugged in, it doesnt use some of the voltage created by the alt. so it "overcharges the battery." voltage measured at the battery is 17,18 volts when headlight isnt plugged in. i plug it back in and its at 13-14.5 volts at the battery. what im getting at is im looking to replace the headlight i have with a 7" LED light bar headlight. im not sure if my battery will overcharge if i replace this strong headlight i have now.

has anyone experienced this issue and do you think i could replace the headlight?
Thanks for reading

 

[aldo5468]

First, find some way to double-check the accuracy of your meter reading - if your meter operates off a small battery and it's nearly dead, the meter may not read accurately - ask me how I know! If it is accurate, your voltage regulator may not be doing its job.

 

[xs650custombuildzz]

First, find some way to double-check the accuracy of your meter reading - if your meter operates off a small battery and it's nearly dead, the meter may not read accurately - ask me how I know! If it is accurate, your voltage regulator may not be doing its job.

its a new regulator and meter.

 

[xs650custombuildzz]

when the headlight is plugged in the whole system is working properly

 

[Jim]

its a new regulator and meter.

New doesn't necessarily equate to accurate and working properly. Just sayin'.....
17-18v is overcharging.... no two ways about it. Since the regulator "regulates" voltage....

 

[mike in idaho]

Is the regulator properly grounded?

 

[RustiePyles]

The electrical system of the bike is designed to have the load of the headlight in the circuit at all times. Your system is a 12vdc system, so 13-14vdc at the battery is what its supposed to be. Why would you want to run without a headlight anyway? Most states require the headlight of a motorcycle to be on at all times while you're riding. But if your battery is overcharging, your voltage regulator is not cycling and its allowing the battery to charge constantly. What kind of charging system and regulator rectifier do you have?

 

[RustiePyles]

If you want to install a low draw LED light and need to simulate a load, just measure the impedance of your headlight and the new LED light. The difference in impedance (load) can be simulated with a resistor of the proper size added to the circuit.

 

[Team Junk]

It sure smells of a ground problem at the regulator or battery grounds. Clean grounds.

Is it the right regulator ? Pictures

 

[Team Junk]

Why would you want to run without a headlight anyway? Most states require the headlight of a motorcycle to be on at all times while you're riding.

I think what he is doing is looking at what the system does. Good thing since there is a fault. In the end I think he intends to run the light bar at all times like the regular headlight.

I suspect he may have a PMA.

 

[Paul Sutton]

My experience: The stock 81 SH regulator controls at approximately 14.3V whether or not the headlight is on as long as the motor is running above 1500rpm. 17 - 18V should never be seen.

 

[xs650custombuildzz]

The electrical system of the bike is designed to have the load of the headlight in the circuit at all times. Your system is a 12vdc system, so 13-14vdc at the battery is what its supposed to be. Why would you want to run without a headlight anyway? Most states require the headlight of a motorcycle to be on at all times while you're riding. But if your battery is overcharging, your voltage regulator is not cycling and its allowing the battery to charge constantly. What kind of charging system and regulator rectifier do you have?

with the headlight connected it recharges correctly. im not trying to run it without a headlight i want to change it to an LED lightbar headlight

 

[xs650custombuildzz]

I think what he is doing is looking at what the system does. Good thing since there is a fault. In the end I think he intends to run the light bar at all times like the regular headlight.

I suspect he may have a PMA.

i have a pamco ignition if thats what ur wondering

 

[xs650custombuildzz]

It sure smells of a ground problem at the regulator or battery grounds. Clean grounds.

Is it the right regulator ? Pictures

i believe the reg. is off of mikes

 

[Team Junk]

Is it a stock alternator with brushes or a aftermarket PMA from mike's ?

 

[xs650custombuildzz]

Is the regulator properly grounded?

you might be onto something there i will check tmrw, i think its grounded right to the battery tho.

 

[xs650custombuildzz]

just to be clear, this is not a stock xs650 its a cafe racer with a dif headlight

 

[xs650custombuildzz]

Is it a stock alternator with brushes or a aftermarket PMA from mike's ?

it is an stock alt from ricks motorsports electric off of PU

 

[xs650custombuildzz]

Is it a stock alternator with brushes or a aftermarket PMA from mike's ?

with brushes

 

[Team Junk]

stock with brushes.

Aftermarket PMA