Headlight Adjustment ????

[pro10is]

Ok, I'll take a stinkin' shot at this. No guarantees. If I get it wrong blame it on too many late night parties before trig class.:cheers:

Assumptions:
Spyder GS/RS/RS-S Headlight Height: 32.375" on average w/200 lb driver. (This could change considerably with a heavier/lighter driver, cargo load, tire pressure, performance shocks, etc.)
BRP Specs for Headlight Adjustment: Adjust for a low beam height of 24.0" to 27.5" (25.75" halfway point) at 33' with a 200 lb driver.

If the Headlight Height is 32.375" and we assume if the low beams were adjusted to shine on the wall at this height at 33' (or any realistic distance), they could considered to be parallel. Yes I know there are other factors involved, but this is just a reference point for a parallel beam adjustment which we'll call 0°. BRP calls for the proper height adjustment to be 25.75" at 33'. So the delta is: 32.375" (parallel height) minus 25.75" (BRP Adjustment Height) for a difference of 6.625". Using right angle trig where side "a" is 6.625" and side "b" is 33' (or 396"), angle "A" or the head light adjustment angle can then be calculated out to be 0.96°. So BRP is effectively saying that the low beams should be adjusted downward by only about 1° from parallel.

Now that we know the adjustment angle we can use it to interpolate the low beam adjustment height for other distances. (I'll spare you the math):
[TABLE="width: 500"]
[TR]
[TD]Angle
[/TD]
[TD]Distance[/TD]
[TD]Low Beam Height Adjustment[/TD]
[/TR]
[TR]
[TD]0.96°[/TD]
[TD]33'[/TD]
[TD]24.0" - 27.5"[/TD]
[/TR]
[TR]
[TD]0.96°[/TD]
[TD]30'[/TD]
[TD]24.6" - 28.1"[/TD]
[/TR]
[TR]
[TD]0.96°[/TD]
[TD]25'[/TD]
[TD]25.6" - 29.1"[/TD]
[/TR]
[TR]
[TD]0.96°[/TD]
[TD]20'[/TD]
[TD]26.6" - 30.1"[/TD]
[/TR]
[TR]
[TD]0.96°[/TD]
[TD]15'[/TD]
[TD]27.6" - 31.1"[/TD]
[/TR]
[TR]
[TD]0.96°[/TD]
[TD]10'[/TD]
[TD]28.6" - 32.1"[/TD]
[/TR]
[/TABLE]

The closer you try to adjust it the harder it will be. The beam center point will be harder to determine and the height will be trickier to set. I wouldn't try it any closer than 20'.

This is just an exercise in math and other factors can change these numbers so use at your own risk, but this should at least get you in the ball park. I still prefer adjusting the desired height relative to the current position and then testing it out on a long, straight stretch of road at night. That's how I adjust mine.

 

[Bob Denman]

:shocked:
That was very informative... :thumbup: I think! :shocked:
This really is a serious question, and I've been probably guiltier than most in making a joke out of it; mostly because I've never played well with Mathematics... :gaah:
But I think that you've got it nailed down! :2thumbs:
So Randy...Give us back Holly or we'll boot you out of the Spyderlover's Hall of Fame!

 

[bluestratos]

When I installed my HIDs I marked the garage door (inside) off of resonably level slab. When I was done with the install I set the lights to that hieght but to be sure I went out that night into a church parking lot and set them up according to the book. It showed I was way to high so I reset and went for a ride. The lights were so low the road ahead was way too dark. I went home and reset them to the taped marks on the garage door. This is where I have left them since and no cars are flashing so I bet I am close. I want to take our car out and test in real time to see if I can move up a smidge or not. Low beam is not bad but high beam still seems to be off. I am getting some PIAs next week from the same vender I bough the HIDs from so I hope I can use these to fill in abit.

 

[pro10is]

When I installed my HIDs I marked the garage door (inside) off of reasonably level slab. When I was done with the install I set the lights to that height but to be sure I went out that night into a church parking lot and set them up according to the book. It showed I was way to high so I reset and went for a ride. The lights were so low the road ahead was way too dark. I went home and reset them to the taped marks on the garage door. This is where I have left them since and no cars are flashing so I bet I am close. I want to take our car out and test in real time to see if I can move up a smidge or not. Low beam is not bad but high beam still seems to be off. I am getting some PIAs next week from the same vender I bough the HIDs from so I hope I can use these to fill in abit.

The problem with aftermarket HID bulb replacements is that the OEM halogen bulb reflectors were not designed for them and the focal point may change. The light may scatter. This is precisely why BRP's optional HID kit includes new reflectors specifically focused for the HID bulbs they used and is thus so expensive. It's also why aftermarket HID replacement bulbs are not DOT approved. The better aftermarket HID bulb manufacturers try to laser adjust the light source in an attempt to match the original halogen bulb as close as possible but that's not easy or precise. So adjusting the height for non-BRP HID's is going to be tricky. Still, with some luck, you can get very good results.

 

[zlkenz]

light alignment

a quick but fairly accurate way with only ten feet level ground infront of the spyder is to measure the height from the ground to the centreof the low beam lights and mark it on the wall then mark two inches below that as your target top edge of your low beam line. the spyders have anice sharpcut off line so an accurate way to check when you are sitting on it.

 

[billybovine]

euro vs. na

a quick but fairly accurate way with only ten feet level ground infront of the spyder is to measure the height from the ground to the centreof the low beam lights and mark it on the wall then mark two inches below that as your target top edge of your low beam line. the spyders have anice sharpcut off line so an accurate way to check when you are sitting on it.

This would be close for euro lights but I would go for 2 1/2 inch for north american lights.

 

[pro10is]

I posted this chart last Friday based upon mathematical calculations. This weekend I finally had a chance to try it out on my RS-S and it works so you can now use the chart with confidence.

[TABLE="width: 500"]
[TR]
[TD]Angle
[/TD]
[TD]Distance[/TD]
[TD]Low Beam Height Adjustment[/TD]
[/TR]
[TR]
[TD]0.96°[/TD]
[TD]33'[/TD]
[TD]24.0" - 27.5"[/TD]
[/TR]
[TR]
[TD]0.96°[/TD]
[TD]30'[/TD]
[TD]24.6" - 28.1"[/TD]
[/TR]
[TR]
[TD]0.96°[/TD]
[TD]25'[/TD]
[TD]25.6" - 29.1"[/TD]
[/TR]
[TR]
[TD]0.96°[/TD]
[TD]20'[/TD]
[TD]26.6" - 30.1"[/TD]
[/TR]
[TR]
[TD]0.96°[/TD]
[TD]15'[/TD]
[TD]27.6" - 31.1"[/TD]
[/TR]
[TR]
[TD]0.96°[/TD]
[TD]10'[/TD]
[TD]28.6" - 32.1"[/TD]
[/TR]
[/TABLE]

The chart is for GS/RS models only with a stock headlight height of 32.375" (32 3/8") on average (w/200 lb driver). If your headlight height is higher or lower due to mods just let me know and I can supply you with a custom chart that will work for you. Also if someone can give me the center line height of the RT headlights I can calculate a chart for those too. Thanks, Jim

 

[Bob Denman]

Thanks Jim! :clap: :firstplace: :2thumbs:

 

[arntufun]

Thanks Pro10is !!!!!! :firstplace: Your one of the reasons why my IBM stocks are almost $200.00 each. :yes::firstplace::yes:

 

[wyliec]

Thanks Pro10is !!!!!! :firstplace: Your one of the reasons why my IBM stocks are almost $200.00 each. :yes::firstplace::yes:

Randy,

I'm sure glad I went back and read your original post. I think pro10is would have been all over me if I asked what I was going to.

 

[ICE]

RT center line with Elka Shocks

Hi Jim, the center line of my RT is 35 inches without rider. Appreciate the math...there's a reason I've owned IBM stock for over 30 years.

 

[Bob Denman]

opcorn:opcorn: nahhhh... Switching to barbeque!

Can't wait to see what the chart will look like... :thumbup:

 

[pro10is]

Ok here's the RT chart. Thanks ICE for the RT headlight height.

Assumptions:
Spyder RT Headlight Height: 35.0" (This could change with a heavier/lighter driver/passenger, cargo load, tire pressure, performance shocks, etc.)
BRP Spec for Headlight Adjustment: Adjust for a low beam height of 25.3" to 28.8" (27.1" halfway point) at 33' with a 200 lb driver.
Calculated Angle: 1.15° downward

[TABLE="class: cms_table, width: 500"]
[TR]
[TD]Angle
[/TD]
[TD]Distance[/TD]
[TD]Low Beam Height Adjustment[/TD]
[/TR]
[TR]
[TD]1.15°
[/TD]
[TD]33'[/TD]
[TD]25.3" - 28.8"
[/TD]
[/TR]
[TR]
[TD]1.15°
[/TD]
[TD]30'[/TD]
[TD]26.0" - 29.5"
[/TD]
[/TR]
[TR]
[TD]1.15°
[/TD]
[TD]25'[/TD]
[TD]27.2" - 30.7"
[/TD]
[/TR]
[TR]
[TD]1.15°
[/TD]
[TD]20'[/TD]
[TD]28.4" - 31.9"
[/TD]
[/TR]
[TR]
[TD]1.15°
[/TD]
[TD]15'[/TD]
[TD]29.6" - 33.1"
[/TD]
[/TR]
[TR]
[TD]1.15°
[/TD]
[TD]10'[/TD]
[TD]30.8" - 34.3"
[/TD]
[/TR]
[/TABLE]


If for any reason the height of your RT headlights are higher or lower than 35" just let me know and I'll calculate a custom chart for your specific RT. Thanks, Jim

 

[Bob Denman]

:2thumbs::2thumbs: :bowdown::bowdown::bowdown::bowdown: :firstplace:

 

[BLUEKNIGHT911]

HEADLIGHT AIMING

Make this easy on yourselves, if you riding/driving and its dark turn on you're lights ....if you can see you are good to go....they are doing their job.....the last time some official checked my headlights for accuracy was........Never.........Less Stress is Best.....Mike.....and Scotty you weren't suggesting that Holly weighs 200 lbs were you ??? :roflblack::roflblack::roflblack:.......

 

[billybovine]

other users of the road

Make this easy on yourselves, if you riding/driving and its dark turn on you're lights ....if you can see you are good to go....they are doing their job.....the last time some official checked my headlights for accuracy was........Never.........Less Stress is Best.....Mike.....and Scotty you weren't suggesting that Holly weighs 200 lbs were you ??? :roflblack::roflblack::roflblack:.......

If the oncoming driver has to look away because of excessive glare and accidently stears into your lane I think that is a problem.