Steve Saunders Goldwing Forums banner

Status
Not open for further replies.
1 - 8 of 8 Posts

·
Premium Member
Joined
·
537 Posts
Discussion Starter #1
imported post

Can anyone tell me how much voltage it takes to operate a headlight [ quartz bulb] 12 V 60/55 W ? While riding my 1987 1200A will show only 12V. If I pull the fuse for it, the voltage goes up to 14 V plus. Is this right?

Thanks guys Alski
 

·
Premium Member
Joined
·
700 Posts
imported post

If I understand your question, then here's an answer. The headlight takes about 11-14 volts - but that isn't really what your voltmeter is reflecting. If I understand how the voltmeter on the Wing works, what it's really showing is the amount that your system is charging to. So, the headlight pulls a lot of current (5 amps, right?), so when you pull its fuse, the system devotes that amount of power back to charging the battery.

Mine will hit 12 at lights, sometimes lower, but will pull about 14 at highway speeds.

I'm sure you'll get more answers about how much charge you should be showing....

Jack
 

·
Premium Member
Joined
·
2,491 Posts
imported post

alski425 wrote:
Can anyone tell me how much voltage it takes to operate a headlight [ quartz bulb] 12 V 60/55 W ? While riding my 1987 1200A will show only 12V. If I pull the fuse for it, the voltage goes up to 14 V plus. Is this right?

Thanks guys Alski
Alski,


12 volts @ 55 watts = 4.58 amps
14 volts @ 55 amps = 3.92 amps

12 volts @ 60 amps = 5 amps
14 volts @ 60 amps = 4.2

Your charging system runs around 0 amps into the battery at base idle & maybe 3-5 amps at 3000-4000 RPM’s .. With the cooling fan & lights running at 1000 RPM idle you will be lucky to have 12-12.4 volts at idle.. Traveling down the road at 3000+ RPM’s you should show between 14 & 15 volts system voltage with probably around 1-5 amps into the battery depending on battery state of charge.

Twisty
 

·
Premium Member
Joined
·
537 Posts
Discussion Starter #4
imported post

Uh huh! thats why me and electricity [that stuff u cant see] dont get along. I have done most everything mechnical but that electricity I just dont know. thanks everybody. I,m still in the "dark".

Alski
 

·
Premium Member
Joined
·
4,882 Posts
imported post

I think twisty is trying to remind us of ohms law... If I remember it right you put your legs in the lotus postion , hands on knees with palms up, look serene and say ohm very slowly
 

·
Premium Member
Joined
·
537 Posts
Discussion Starter #6
imported post

To ohm it may concern. An ohm is not a volt.

Alski
 

·
Premium Member
Joined
·
2,491 Posts
imported post

alski425 wrote:
To ohm it may concern. An ohm is not a volt.

Alski

Alski, when working with ~lectricty it helps to think in terms of water believe it or not..
Volts would be water pressure & Amps would be water volume (amount)..
Think in terms of a garden hose-- You need BOTH pressure (water pressure) & flow (gallons per minute) to water your lawn.. If you have lots of pressure but not much flow it won’t water very much & if you have lots of flow but no pressure it won’t go very far from the end of the hose..

It’s the same with those little electrons that like to travel through your wires. They need both pressure & flow (volts & amps)..
Do to battery design, wire size requirements, charging system capacity most motorcycles & automobiles use a standard voltage of 12 volts DC (actually 12.6 or so to be exact).. Problem is, you can’t re-charge a lead acid motorcycle battery at the same voltage it operates at so most charging systems operate at some where’s around 14-15 volts.. That also means the bike is operating at that same 14-15 volts when the engine is running at normal road speed.. Now voltage alone won’t light a light or operate an ignition coil, it also takes a certain amount of flow (amps) to maintain that 14-15 volts to a headlight (etc) when it is using the power.. So you need both the operating volts & the amps (flow) to make a light light, or a motor motor. A combination of the volts & amps is the Watts rating you see things rated at.


On your motorcycle, the charging system produces somewhere around 36 amps at 14-15 volts (that’s at probably 4000 engine RPM’s+).. Once all your lights & accessories are on & using power they probably use up close to 30 or more of those amps (flow) so that only leaves a few extra amps to flow to the battery. Now if your engine is running at 2000 RPM’s the charging system probably only produces 20-25 amps (a guess here).. If you still have all those lights, cooling fan, brake lights, radio, etc. on you are still using 30 or so amps, but your bike is only producing 20-25 amps.. To keep all those accessories operating the remainder of the amps must flow back out of the battery into the bikes electrical system.. Any time you are using more power than you can make the (bike’s) system voltage starts to drop do to old mr. Ohm’s law so that is what you see in your voltmeter reading..


Ask all the questions you want to here & some of us willtry to try to answer them for you..


Twisty
 

·
Premium Member
Joined
·
4,882 Posts
imported post

amps = watts/volts therefore a 36 amp light on a 12 volt system = 3 amps

never could get my legs into that @#%%@# lotus position

a 12V 60/55 W bulb takes.... 12 volts however at 60 watts it draws 5 amps

if all of your accesories , lights etc, draw more amps than the alternator is producing you will draw the needed power from the battery. as the battery discharges its voltage drops. when you disconnect something and the system is drawing less than the alternator produces, the voltage goes back up (and the battery re-charges).
 
1 - 8 of 8 Posts
Status
Not open for further replies.
Top