HID’s (High Intensity Discharge) explained

Introduction to HID’s:

HID is an acronym for High Intensity Discharge. HID is a more efficient way of producing light than the conventional filament-based bulb. Most light bulbs that we use everyday are filament based, which is a tiny spiral of tungsten metal inside of a sealed quartz glass bulb filled with halogen gas, which combines with tungsten vapor when a current is applied and emits light. Halogen headlamp bulbs produce from 800-1300 lumens of light with a color temperature of approximately 3200k. Here is something that you might not know, a halogen bulb is approximately only 9% efficient.

HID lights work on a different principle. Electrical current is used to produce an arc of light between two electrodes inside a sealed capsule containing xenon gas and other elements like mercury and metal halide salts. Too complicated? Basically think of it as a bulb with no filament, and only filled with Xenon gas, which produces light when electricity is passed through it.

HID’s require complicated electronics known as ballasts and ignitors. Which is basically the small box that comes in the HID kit. HID’s are approximately 85% efficient, which is way more than its halogen counter parts. Even the best halogen headlight bulbs provide outputs in the range of 1300 lumens from a 55W bulb. HIDs are able to provide output in the range of 3200 lumens using a 35W bulb, which is nearly triple the usable light of a halogen light.

Main HID components:

The HID capsule is similar in appearance to a halogen bulb, but upon closer inspection we can see that they are quite different. The Ballast controls the current to the HID bulb. A typical HID bulb needs 85 volts of current at 35 watts to function, though newer capsules accomplish this with only 42 volts. This high demand of power is why the ballast is important in the HID kit.
Ballasts often appear as small metal cases roughly the size of a deck of playing cards. An ignitor works with the ballast and provides several thousand volts of rapidly pulsed current between the electrodes to start heat up the materials in the bulb. You can see the ignitor work by simply turning on an HID system — the quick flash you see is the ignitor providing the ultra-high voltage needed to start the HID system.
Ignitors can be contained within the ballast assembly to reduce complexity, or they can be a separate assembly just before the HID capsules.
In summation, there are 3 main components to an HID lighting system: -The “bulb capsule”, this produces the actual light -Ballast: turns the bike’s 12V into 85V for the capsules to work -Ignitor: ignites the metal salt in the capsule at startup

HID HEADLAMP:

HID systems are not just the capsules and ballasts/ignitors. HID systems rely on special headlamp designs to maximize their light output. Why is this important? read on.

HID capsules do not spread their light 360 degrees like a filament-based bulb does. This means that the lenses and reflectors must aim the light in a very specific way or there will be large hotspots and dark areas. Looking head-on at an HID capsule, there is a yellow/orange area pointing downwards. This area always points down, regardless of how the capsule is rotated. HID headlamp systems actually block this area entirely. If not blocked, a strange yellow area would be projected on the ground, causing the rest of the headlamp to appear discolored. Some systems spread this yellow area out across a very wide area so as to make it hard to see.

There is also something known as a return-wire shadow. The small ceramic insulator that runs the length of the glass will actually cause a dark spot if the capsule is viewed head-on.

Clear Projectors The projectors appear to be perfectly clear and have a smooth surface. Clear projectors give better forward illumination at the expense of spread (side-to-side illumination).

Ribbed Projectors The projectors appear to have bands or ribs across them horizontally. This helps spread the light to the sides more effectively, but decreases the forward distance you can see.

In short how good a projector is, is decided by the lens system used. 

HID capsules undergo a process known as color shifting. The first 100 hours may have the light producing a more yellow looking color, this is completely normal and safe. After the first 100 hours of operation, the salts will begin to change their color slightly as they are “broken in”. By the time the 500 hour mark is reached, the color will have shifted up by as much as 250k. The coloring will be slightly more blue. Colorshiting will continue until the bulb no longer function. The shifting is extremely gradual and low.

An important fact to consider is that higher color temperatures will make things appear differently. Street signs are designed to be viewed with particular color temperature lights, and a non-standard color may alter their appearance. The same applies to road markers and emergency vehicles.

HID SAFETY & LONGEVITY:

HID systems are complicated and potentially dangerous if you are careless and sloppy in their installation and use. They can also wear out very quickly if you do not install and maintain them properly. This section will discuss how to keep yourself safe, and how to ensure your HID system functions for years to come.

The ballast and ignitor is carrying roughly 23,000V at 85W. You should never work on an HID system that is plugged in and turned on. Disconnect the system and remove it from the bike if possible.
You should never, under any circumstances, open up the electronics. A short-circuit could send stored charge in a capacitor into your body. You also risk damaging the electronics. Ensure that your wiring is well-insulated and has good grounding points. Any tears in the insulation should be repaired immediately. Inspect your wiring regularly for any damage. Good grounding points will help the system function properly, and will keep you safe.

Handle the bulbs with care. The tiny glass bulbs are pressurized at nearly 100ATM,  breaking this will send glass flying into your skin, and will release toxic gases. Wear gloves if possible. This will keep the oils from your skin off the bulb.

HID systems can last for more than 2500 hours if installed and cared for correctly. Although HID systems are somewhat of an “install and forget” component, there are some simple tasks you can perform during and after installation to improve longevity.

First and foremost, mount and secure everything tightly. Loose components will vibrate and wear out more quickly. Capsules should seal tightly into the headlamp housing, and should have virtually no play when wiggled. Ballasts and ignitors should be securely fastened as well.
Periodic inspections of the system will help you find any problems. Double-check that the wiring is not cut or torn, and that insulation is still holding. Wiggle the electrical connectors to ensure they are still snug.
Follow the 5-minute rule. If you must power on the system, let it run for at least 5 minutes. This ensures that the salts reach their optimal operating temperature. Short usage times will severely decrease the useful life of the salts, meaning colorshift will occur much more quickly. If you turn the system off, keep it powered down for at least 5 minutes so the salts can properly return to a powder.
Never run the HIDs for more than 3 hours at a time. After 3 hours, let the system stay powered off for 5 minutes or more before you turn it on again. This may make nighttime ride more tricky, but it will give you a chance to pull over and rest.

CONCLUSION:

HID systems are a great way to improve your nighttime visibility and even improve the looks of your bike. With nearly three times the usable light of a halogen bulb, you are making an investment in your safety. Be weary of aftermarket HID kits, there are many cheap systems that use poorly-designed components. Stick with the big brands, and make certain they are reputable and legitimate sellers. You truly do get what you pay for in HID kits.

HID headlights have received mixed reviews from bikers as they produce quite a lot of glare for other bikers/drivers and can be quite blinding through rear view and side view mirrors.

The best benefits of xenon HID lights are the most obvious direct benefits that they offer. They are a lot more durable than halogen lights. They can withstand a greater amount of vibration and shock from the road due to there being no filament. There is also much greater life span. Xenon gas will last up to 10 years; this is about 3 times longer than halogen. As an end result this will save us money and any trouble dealing with a blown out light at night. Of course with a light that is 3 times as bright you may think that it also consumes 3 times as much power…Wrong! Xenon lights consume 25% less power than standard headlights and produce 200% more light.