New to the LED idea, need a bit of help

[weldman66]

Hello,

It might have been asked before here so please forgive me for the redundancy. I've heard many talks in different forums about the LED lights and would like to clear up any misconceptions in my mind. I'll will be asking these questions in pertaining to my motorcycle.

I'm looking to lessen the load on my overworked charging system on my '86 Yamaha Venture Royale. I really dont have a technical head for electrical systems, I have a general understanding in that so many watts take up so many amps on a charging system. My understanding is that LED lights take less watts to produce an equal amount of light that is produced in a standard bulb.

That being said is this true? and by how much is the decrease. I'm looking at trying to upgrade the charging system on the bike and need all the help I can get.

Thank you in advance   Brad

[Rob]

Hi Brad, and welcome to the boards.

You have the right idea. LEDs draw less current than incandescent bulbs, and so they'll put less of a strain on your charging system.

Here's some fairly simple math to help illustrate:

Watts = Volts * Amps, and Volts is usually 12-13 for vehicles, we'll use 12 to stay consistent with other discussions you may see.

So if your charging system is rated at 600W for example, you have the ability to source (600/12 = ) 50 Amps.

To give you an idea of the difference LED lighting can make, you may have to do some calculations., if only to compare apples to apples, or in this case Watts to Watts.

A typical brake light may have dual filaments, and be rated 21/5W, meaning it dissipates 21W when the high filament is lit, and 5 when the low is lit.

LED solutions vary (there's not really much standardization yet) but typically draw less than a few hundred milliamps depending on the size of the array, placing you in the 1 Watt ballpark. Check the specs on the solution you're considering, and multiply milliamps * 0.012 to get Watts, or multiply Amps * 12.

The other big win with LEDs is life expectancy. The LEDs themselves have a lifetime of at least tens of thousands of hours, versus the few thousand hours for a filament bulb. The assembly needs to be well-constructed in order for the lifetime of the unit to equal the LED lifetime though, so don't buy cheaply made retrofits. If you build your own array, seal it in epoxy to keep it from shaking apart under road vibration.

[weldman66]

Hello Linear,

Thank you for the welcome, I am going to try this conversion over to the LED lights I have just 1 more question. I have heard in a previous discussion about running an inline regulator for lack of it's technical name.

My question is can I put this directly in line after the fuse box and have it regulate the lighting system or do I have to chase wires and install several separately. I dont plan on on putting LED's on all the lights I'll be leaving the tail light bulbs in as I want the radiant light abilities of the 1157 for the rear tail light assembly.

I do appreciate your input  Thanks in advance  Brad

[Rob]

Without looking at a diagram, I'm hard pressed to offer any specifics. But I think your statement

I'll be leaving the tail light bulbs in as I want the radiant light abilities of the 1157 for the rear tail light assembly.

rules out the simplified arrangement you describe.

The other thing to remember about a regulator circuit is that it's using some power to do its regulation--there's no free lunch. So if you're budgeting power from your charging system, the regulator approach may not give you the wins that a cheaper, simpler, resistor current limiter will.

(standard disclaimers apply, etc. Since we aren't talking specifics consider the above a general observation rather than a hard and fast rule.)