LED headlight replacement for H4

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Zombie Master
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LED headlight replacement for H4

Post by Zombie Master » Tue Sep 05, 2017 12:33 am

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
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hal
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Re: LED headlight replacement for H4

Post by hal » Tue Sep 05, 2017 2:46 am

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

'74 R90/6
'97 R850R
'05 Subaru Forester

Wobbly
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Re: LED headlight replacement for H4

Post by Wobbly » Tue Sep 05, 2017 3:17 pm

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.
After 20 years as a professional bike mechanic and 30 years as an engineer I know just enough to be dangerous !

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Zombie Master
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Re: LED headlight replacement for H4

Post by Zombie Master » Tue Sep 05, 2017 4:42 pm

Excellent Wobbly....I'm turning my disco lamps off permanently!
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dougie
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Re: LED headlight replacement for H4

Post by dougie » Tue Sep 05, 2017 5:41 pm

Zombie Master wrote:
Tue Sep 05, 2017 4:42 pm
Excellent Wobbly....I'm turning my disco lamps off permanently!
And lose the onboard vibrator! :lol:
I've spent most of my money on women, motorcycles, and beer.
The rest of it I just wasted.

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Zombie Master
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Re: LED headlight replacement for H4

Post by Zombie Master » Wed Sep 06, 2017 1:10 am

dougie wrote:
Tue Sep 05, 2017 5:41 pm
Zombie Master wrote:
Tue Sep 05, 2017 4:42 pm
Excellent Wobbly....I'm turning my disco lamps off permanently!
And lose the onboard vibrator! :lol:
http://www.viberider.com/
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dougie
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Re: LED headlight replacement for H4

Post by dougie » Wed Sep 06, 2017 9:33 am

Zombie Master wrote:
Wed Sep 06, 2017 1:10 am
http://www.viberider.com/
:o :shock: :o :shock: :o :shock:
I've spent most of my money on women, motorcycles, and beer.
The rest of it I just wasted.

Rob
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Re: LED headlight replacement for H4

Post by Rob » Thu Sep 07, 2017 2:51 pm

Zombie Master wrote:
Wed Sep 06, 2017 1:10 am

http://www.viberider.com/
"Deal closer"... :roll:

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

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Zombie Master
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Re: LED headlight replacement for H4

Post by Zombie Master » Fri Sep 08, 2017 2:31 am

If you have to ask....you wouldn't understand.
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ME 109
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Re: LED headlight replacement for H4

Post by ME 109 » Fri Sep 08, 2017 6:52 am

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.
Lord of the Bings

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