Power drain with headlight on..

[Anonymous]

Have a 1981 GS550T in good running order. I have noticed that when I have bike at idle, and then turn on high beam, that engine rev's drop by at least 1k. Is this normal? If bike is warm and has been run for awhile, engine revs only drop by 500. Should I check for bad connections or wires? I will be checking the stator this winter..

Thanks

 

[earlfor]

Re: Power drain with headlight on..

Since you have a 1981 model, I assume your headlight has no on/off switch and the only choice you have is high or low beam.
I think the most likely fault would be a corroded connector on the high beam wire inside the headlight shell, or corrosion on the socket that the headlamp plugs into. Next most probable would be the switch contacts for the high beam. No, a loss of 1000rpm is not normal for turning on the high beam.

Earl

Have a 1981 GS550T in good running order. I have noticed that when I have bike at idle, and then turn on high beam, that engine rev's drop by at least 1k. Is this normal? If bike is warm and has been run for awhile, engine revs only drop by 500. Should I check for bad connections or wires? I will be checking the stator this winter..

Thanks

 

[Anonymous]

Re: Power drain with headlight on..

Actually I do have an on/off switch as well as a high/low beam switch. I assume that the problem most likely remains the same. So I will take apart the shell and check the wire connections on the headlamp. I already looked in there, and man what a mess of wires 8O ..any info on which to follow?

Since you have a 1981 model, I assume your headlight has no on/off switch and the only choice you have is high or low beam.
I think the most likely fault would be a corroded connector on the high beam wire inside the headlight shell, or corrosion on the socket that the headlamp plugs into. Next most probable would be the switch contacts for the high beam. No, a loss of 1000rpm is not normal for turning on the high beam.

Earl

 

[Anonymous]

rhpassmore, I looked at the Clymer manual wiring diagram. The headlight has three wires running off, they are BLACK/WHITE, WHITE(I think), YELLOW. The Yellow is the one that runs to the High beam side of the switch, the white is to the low beam. If it is corrosion in any of the places earlfor mentioned these are the wires to check. Oh and what I think earlfor meant about the ON/OFF switch is that it is locked in the always on position.


Hope this helps

Moonshine550t

One more thing that Yellow wire branches off and runs to the Highbeam indicator.

 

[Anonymous]

Thanks for the info, I will look.
And as for the ON/OFF Is it always in the on position? I have On (up) and Off (down) switch as well as a High/Low beam switch.

rhpassmore, I looked at the Clymer manual wiring diagram. The headlight has three wires running off, they are BLACK/WHITE, WHITE(I think), YELLOW. The Yellow is the one that runs to the High beam side of the switch, the white is to the low beam. If it is corrosion in any of the places earlfor mentioned these are the wires to check. Oh and what I think earlfor meant about the ON/OFF switch is that it is locked in the always on position.

Hope this helps

Moonshine550t

One more thing that Yellow wire branches off and runs to the Highbeam indicator.

 

[Anonymous]

Yep, that is how my On/OFF switch is, the little plastic cover thing has a tab on it that keeps it from moving up and down. I had to take the little screw that holds it on out to turn the light on and off. The previous owner of your bike might have cut the tab off. I don't have to worry about that tab I can't even find the cover anymore.


Moonshine550t

 

[SqDancerLynn1]

HOW fast do you have the idle set for it to drop 1K RPMs If it drops 50-100 thats different it could just be the load from the stator trying to work harder to keep up with elect load, could be bad connections too.

 

[Anonymous]

idle ar 1500.

HOW fast do you have the idle set for it to drop 1K RPMs If it drops 50-100 thats different it could just be the load from the stator trying to work harder to keep up with elect load, could be bad connections too.

 

[earlfor]

1500 is a little high. It should be around 1000.

Earl

idle ar 1500.

 

[Anonymous]

Actually the reason your RPM's drop when you turn on your headlight is b/c the voltage drops going to the ignition coils. the system voltage drops when the load from the headlight and tail light is applied, then add the resistance from the undersized wire that suzuki is known for and you probably would be lucky to have 10 volts at your coils at idle. when you figure that the coils typically tranform 12 volts to 30,000 to 50,000 you can see that at 10 volts the colis are only able to produce a fraction of the intended voltage. Now, a spark plug will spark at a given voltage (usually alot lower then the coil can produce), but the current isn't there so the spark is considerable weaker. 8O
The stator in a GS series is a permant magnet type and does not turn harder when more load is applied to the electrical system. when the electrical demands is low on your bike,( battery fully charged and the headlight off) the regulator just bleeds the excess voltage off to ground. that's why suzuki runs one winding of the stator to the headlight switch, with the headlight off you only have 2/3 of the wattage from your stator available. That's one of the biggest advantages of the electrex stator rectifier system,, they forget all that and just regulate all three phases of the stator and eliminate about 15 feet of undersized wire and 5 or so dirty and old connectors. Much more desireable system and less wasted energy!



Sorry about all the technical mumble jumbo,, but I've spent alot of years in the automotive service industry and understand the electrical systems well!! I hope this helps!!
Matt

 

[Anonymous]

So what you are telling me is to buy a electrex stator?


I will be replacing the stock one tis winter.. we'll see what happens - --

thanks all for all the input!@