LED headlight replacement for H4

[Zombie Master]

84 R100

I installed an LED replacement for my original H4 bulb today. It's much brighter and more conspicuous than the original. I'm wondering about the effects on the charging system. The LED draws 20W on low and 40W on high beam. Could this be a problem for the voyage regulator or charging system? When running my heated vest on tour, I had a rotor fail and would like to be able to run heated grips and a vest. Any thoughts?

Here is what I installed:
https://www.cyclopsadventuresports.com/ ... _p_83.html

[hal]

This draws less than the origional H4 which draws 55/60. So the effect on your chargin system is positiv.

[Wobbly]

I agree with Hal. Most of the new, super-bright LEDs draw around 45W. The OEM bulb drew 55/60W; newer bulbs can go up to 100W ! It's marked on the bulb, so check it.

You burned up your alternator because you tried to pull more electrical power than it was capable of creating. (Realize that the max alternator power is only created while running faster than 2500 RPM. So you still might need to turn your vest OFF at all traffic stops.)

Calculate It
Doing a power budget is very simple. You start with the rated power of the alternator, then subtract the wattage of ALL the items wanting power (headlight, tail lamp, ignition, gauge lights, grip heaters, heated vests, BBQ grill, disco lamps, etc.) Don't worry about blinkers, turn signals, or horn... they are not in use long enough to matter. You must end up with at least +25W remaining to charge the battery.

If you end up with less than +25W, then you'll have to 1) turn some items OFF permanently, 2) buy a lower wattage vest, or 3) buy a higher output alternator.

Lessons
1) You don't get electrical power for free.
2) Just because they sell an accessory doesn't mean your alternator can handle it.
3) The power budget is a guideline for highway use. If you ride around town at low RPM, and/or use your blinkers and brake lamp a lot, then you'll need to turn OFF some items to account for the lower alternator output.
4) You can gain ~15W by converting all your bulbs to LED, which always helps any power budget.
5) Don't forget about TIME. Power leaves the battery very fast, but it can take hours of riding for the battery to recover. Short trips generally never help the battery.

Hope this helps.

[Zombie Master]

Excellent Wobbly....I'm turning my disco lamps off permanently!

[dougie]

Excellent Wobbly....I'm turning my disco lamps off permanently!

And lose the onboard vibrator!

[Zombie Master]

Excellent Wobbly....I'm turning my disco lamps off permanently!

And lose the onboard vibrator!

http://www.viberider.com/

[dougie]

http://www.viberider.com/

[Rob]

http://www.viberider.com/

"Deal closer"...

Are these for NON-big V-twins that can't create their own???

[Zombie Master]

If you have to ask....you wouldn't understand.

[ME 109]

I think you need a 450 or 600 watt EME alternator.
Then you could also run a heated seat, kick ass halogen driving lights, and a coffee machine.
When my stator shits itself, that's where I'm going.