Headlight Aiming

[DiggerJim]

Okay, so I've put a couple new lights on (44W LEDs) & needed to aim them and figured I'd check the headlights as well since I've replaced those with HID bulbs.

 

I go looking for the aiming rule & find 2 that seem to have a fair bit of consensus around them (can't find anything that refers back to the federal regulations that must exist). Both of these two have you sit on the bike a specified distance from a wall (like your garage door) and measure from the ground to the middle of the bulb or light housing, mark that distance on the flat surface in front of you, measure two inches down and focus the lights there. That gives you a 2" drop over the distance you are from the flat surface.

 

The rub is that there are 2 different distances that seem to have some traction out here - either a 2" drop over 25 feet or over 17 feet. Obviously these will result in radically different beam angles. The two references seem to show up with equal frequency except that the 17' distance appears to all trace back to our own Paul Glaves whereas the 25' distance seems to have scattered sources.

 

So, I did mine at 25' & found that the headlights were about dead on so that's a data point in that distance's favor. For now I've aimed the LEDs at that distance as well. However, I'm looking for something definitive as to the "right" drop over distance I should be aiming for.

 

Anyone know what the right distance to measure is?

 

[dirtrider]

 

Morning Jim

 

From the BMW service manual --

 

 

10 meters is 32.8 feet

15cm is 5.9 inches

 

[EddyQ]

Well that equates to 2.7" in 15' or 3.6" in 20'

 

Although, it doesn't seem clear what the cutoff is.

[DiggerJim]

Well that equates to 2.7" in 15' or 3.6" in 20'

Although, it doesn't seem clear what the cutoff is.

Which makes Paul Glaves' 2" in 17' or the other web resources recommending 2" in 25' both too shallow an angle. Which suggests that people following those directions are potentially blinding other cars (or at least making things a bit unpleasant for them). Now I'll have to re-aim my bike lights 'cause I did them 2" at 25' which is about 1/2 as much as the service manual suggests.

[g_frey]

Varying loads make for varying adjustments and don't even think about all the different power bulbs or accessory lights. I usually just set them for each trip with the load on the bike. Love those HIDs.

[dwfindley]

Sorry if I sound confused, but what is the consensus on distance? Is it now the BMW recommendation at 5.9" at 32.8 ft? This is helpful folks.

[DiggerJim]

Sorry if I sound confused

LOL! Aren't we all? The BMW recommended aiming got me a lot of light flashers from oncoming traffic (I have twin 35W HID bulbs in my low beams and twin 44W LEDs mounted under the mirrors). I went back to 2" @ 25'. Paul Glaves' 17' measurement cut off too much light for my taste & left too much of the upcoming road dark.

[dwfindley]

Thanks Jim -- I will try the 2" 25' measure on my 2011 RT. I have front lights on the calipers and PIAA mounted under the headlights. I think checking these settings is a good thing. Thanks much.

[macx]

I've been wondering about that - I've got my ajuster turned as low as it will go and it still looks too high, AND am getting too many flashes from oncoming. (2011 RT)

 

Gonna have to ask the dealer to see if they can't do something to allow it to adjust a little lower - am sure they're gonna have to take some tupperware apart, but the next time in for warranty check at 12k (i'm just hitting 10k since May 1 this year) should be a good time to hit em up on that.