front light bulb help

[lt-drzsm]

ive just changed the front bulb, but it seems to go dimmer when im off the throttle and bright on the throttle, is this normal? ive checked it all out and its all fixed up still, the stock bulb did it aswell so i changed it to try fix it, thanks in advance. ps its an 06 sm

[10guy]

A slight dimming is no big deal, what is the condition of your battery?

[lt-drzsm]

A slight dimming is no big deal, what is the condition of your battery?

good think, it starts every time, ive had no issues with it before

[npm]

Have you done the "free power" mod?

https://www.thumpertalk.com/forum/sho...ght=free+power

[lt-drzsm]

Have you done the "free power" mod?

https://www.thumpertalk.com/forum/sho...ght=free+power

not yet, so you think its the battery? ill charge it and see if the helps

thanks

[npm]

I don't think it's the battery, the battery is only capable of putting out 12-12.5 volts even fully charged. The free power mod takes out some of the bad connections that are known voltage drops/restrictions in the charging system. To say it another way, after the power mod the voltage of the system should be higher. In some bad cases I think the gain has been a volt or maybe more. Higher voltage will make the bulb burn brighter.

Some of you electrical geniuses chime in here if I'm not right.

[lt-drzsm]

im not too worried about the power (electrical), i just want to stop the flickering if i can, if its normal then ill leave it alone

[William1]

Does sound like the battery is a bit weak. Whether the free power mod will make a difference is not known but it is a good thing to do anyways. If the battery is weak, the voltage at idle and low rpms is low, at higher rpms it can climb. It can vary from about 12.8 volts to 14.5 or so.

[lt-drzsm]

Does sound like the battery is a bit weak. Whether the free power mod will make a difference is not known but it is a good thing to do anyways. If the battery is weak, the voltage at idle and low rpms is low, at higher rpms it can climb. It can vary from about 12.8 volts to 14.5 or so.

which would make the light brighter? so charging the battery should help then? now i know how you got all that gas:applause:

[npm]

If the battery is weak, the voltage at idle and low rpms is low, at higher rpms it can climb. It can vary from about 12.8 volts to 14.5 or so.

Not be be too dense here but are you saying if the battery is low it will reduce the charging out put?

[10guy]

Do the free power mod, it will allow you charging system to more fully charge the battery. This describes it here.

Not be be too dense here but are you saying if the battery is low it will reduce the charging out put?

No not reduce the charging output but will not be able to bump the electrical output into the system up maximum because it itself is not up there. Your charging system puts out changing voltage depending on the rpm (to a certain point that is), higher rpm higher voltage. If at idle you are putting out 12.3 volts, if you have a fully charged battery it will be able to chip in the rest to make it 14.2 or whatever. If the battery is weak it may not be able to contribute any to it if it puts out 12.3 or less.

Ask if either of you don't understand and I'll try to explain it another way.

[lt-drzsm]

Do the free power mod, it will allow you charging system to more fully charge the battery. This describes it here.

No not reduce the charging output but will not be able to bump the electrical output into the system up maximum because it itself is not up there. Your charging system puts out changing voltage depending on the rpm (to a certain point that is), higher rpm higher voltage. If at idle you are putting out 12.3 volts, if you have a fully charged battery it will be able to chip in the rest to make it 14.2 or whatever. If the battery is weak it may not be able to contribute any to it if it puts out 12.3 or less.

Ask if either of you don't understand and I'll try to explain it another way.

that makes sense to me, thanks for clearing that up.

[10guy]

that makes sense to me, thanks for clearing that up.

No problem:ride:

[Shawndude]

A battery is almost always a load on the charging system, as you cannot get current flow from lower Voltage to a higher Voltage (same as oil, water, air pressure).

A weak battery is like having an extra headlight bulb running, as the battery itself is using up the power, trying to charge up (but it can't). A healthy battery puts little load on the system....but it's always a load with a running engine, unless you're dropping under the battery voltage (you shouldn't).

The charging voltage is dependent on the load, as the capacity of the system is fairly limited. Once the regulator is fully shut off (maximum output state), that's all the output you can get out of the system.

You say the headlight is flickering. It shouldn't flicker, it should just dim at low RPM, with the brake lights on and maybe turn signals, and get brighter once you raise the RPM and turn off the brake light.

If it's actually flickering like a candle, I'd test the generator.

[William1]

If the battery is weak, the light will be dimmer at idle and noticably brighter when you rev it. A strong, healthy battery the light will not change much if at all. Test by putting a meter on the battery and tuinning the bike. You want to see about 13.5 volts at idle and it go to about 14.5 when reved. A weak battery could be in the low 12 range.

[Noble]

Yes, back to basiscs and the original question. Does the headlight dim at idle or flicker? 2 different things - different problems. If just dims at idle, use a volt meter at the headlight to measure voltage at idle and higher RPM. Something around 12 volts at idle is expected (it will always be a little lower than the battery). Moderate RPM around 13 or above is good. That is normal. If you are seeing significantly lower voltages, there is something wrong.

If you have continuious flicker at idle that goes away above idle, you have lack of battery load stabalizing charging system. Bad connections someplace or bad battery.