Welcome to Netrider ... Connecting Riders!

Interested in talking motorbikes with a terrific community of riders?
Signup (it's quick and free) to join the discussions and access the full suite of tools and information that Netrider has to offer.

Recommended headlight adjustments

Discussion in 'General Motorcycling Discussion' started by Mr Owl PhD, Apr 14, 2016.

  1. #1 Mr Owl PhD, Apr 14, 2016
    Last edited: Apr 14, 2016
    Why do I ask? Well firstly let me say I'm referring to a standard 7" round H4 bulb headlamp whether what I have to say applies to other types I don't know, but this is my experience...

    Recommended setting is to measure the height from the ground to the centre of the headlamp and and make a horizontal line two inches below that measurement on a wall, then there are various suggestions as to how far the bike should be from said wall, 17 feet or 25 feet, but in my experience this distance is moot. I might also mention that having a passenger on the back or a full fuel tank does change the light position slightly but no so much that I found it makes a difference.

    I recently bought a Philips extreme vision 130+ H4 bulb that had a tiny bit of blue on the periphery so it give a yellow light that is not as yellow as standard but not white. After adjusting the light as per the recommended setting, I found to my surprise that while it was brighter it did not really illuminate the road very much further in front of the bike, if at all. The high beam though was noticeably brighter. Ok so I drove around like this for a few weeks moderately satisfied.

    Until just for the hell of it I adjusted the headlamp to be two inches over this line on the wall rather than two inches under. I thought that perhaps it might be a little uncomfortable for oncoming drivers so I made sure it was pointed straight ahead or a little to the left. After a short while I got around to actually testing it by having someone drive the bike towards me while I was on the street and in various positions across the road from the curb to the oncoming traffic, and it was then that I realised that having it four inches higher than recommended did not blind oncoming traffic, all it did was make the headlamps look like a bright pinpoint of light instead of not being visible at all, or barely so during the day.

    Further I note that it does not illuminate the road any further in that the bulk of the light seems to fall not very far in front of the bike, although it is a lot brighter. In the daytime when the headlamp was switched to high beam it was painful to look at and when switched back to low beam, it was definitely a nice bright light but not in any way glaringly bright. In fact it's a lot less glaring that at least half of the cars that ride towards me and being on a bike I'm obviously higher than most standard cars.

    The biggest change I have noticed at night is that warning signs light up like christmas trees which I've never really noticed before. Even in the daytime they light up. When I switch to high beam at night, it is clearly high beam, it is not overly high but does the job perfectly.

    What I'm getting at is that with this modern H4 bulb and the lamp adjusted 4" higher than standard specifications, the headlamp appears to work and do it's proper job as you'd expect it to. I hasten to repeat that I have check it in the day at various locations and there is certainly no problem at all with it's height. Further it seems that warning signs are meant to be lit up otherwise they'd not make them reflective. If I had not done this test myself I would have assumed that it would appear to be a high beam. But I'd have been wrong. I feel much safer and the light works much better.

    I've seen motorbikes in the daytime with their lights on and often I barely notice them which is why I've been thinking about a modulator. No one has flashed me and indeed I would not expect it because it is not at all like when people have their high beam on, if it was I would not leave it like it is. I was a bit concerned at first seeing the street signs lit up during the day, but after double checking it's not overly high in real life and so they must be being illuminated by peripheral light, which is what I guess they are meant to do.

    Defensive riding and being seen are the best things a rider can do for his/her safety and after a few weeks of this I feel a lot safer now. So I put this out there and I'd be please to hear anyone's thoughts about this.
  2. were you adjusting based on you sitting on it?

    and yes, recommended headlight settings are correct :p
  3. #3 Mr Owl PhD, Apr 14, 2016
    Last edited: Apr 14, 2016
    Yep, adjusted while sitting on the bike, and whether it is 'correct' is precisely my point. What exactly is 'correct' is it what the law says, or how it actually works. As it does in no way look like a badly aligned headlight, (unlike very many cars I see) there's no problem. I would have no worries with a police car approaching me from the front as I know it just looks normal. So perhaps the theoretical 'correct' adjustment, is not in fact the adjustment that makes the headlamp work correctly!
  4. #4 oldcorollas, Apr 14, 2016
    Last edited: Apr 14, 2016
    not sure I follow you.... the recommended adjustment basically makes the light hit the road X meters in front of the headlight.. ie where you need it. that may change a bit depending where you usually ride at night, ie, highway, pitch light further forwards.. suburbs, a bit closer perhaps...

    what you seem to have done, is to adjust your headlight so that the main part of the beam will be pointing UP ?
    methinks your adjustment regime may be a little off perhaps..

    the true test though, is if your headlights shine up toward the rear view mirror (or side mirror) of the car in front of you, and if the light is where you need it (ie, on the road, not on the signs above the roadway)

    aim it where you want it though :)
    can you roll to 10m from a wall, and take a pic of the light spread on both low and high beam? maybe the lens has weird spread?
  5. Also, ON/OFF throttling will make it look like you are getting smart with oncoming cars... so something for new riders to be aware of...

    Anyway, Good on you for doing a visual inspection using another rider. I have wanted to do this, but forgotten, CBF etc.. I'm a nomad rider now days so no easy access to riding mates. I normally go by: if drivers are dipping me, my beam is too high.

    Mr Owl made an interesting point about your aperture. Could you do as he asked: With the bike held vertically wheel it right up to a wall so that the front wheel is touching it and than mark on the wall where the centre of the headlamp is. Wheel the bike back 7m and put the headlamp on high and then low beam and take photos of each.
  6. First off those 130/90 are illegal from what I have seen on the Philips info sheet,there for racing only. Its a good idea to use a relay as there is usually a big voltage drop without one. Definitely not me, but I know someone with exactly that setup but with a relay and it is unbelievable the amount of light these through. This person got caught on a ride with others braking down and ended up doing a good 100ks to a place called Windgelo well late on a pitch black night. There was no chance of overrunning this light on hi beam till very very stupid speeds,way beyond kangaroo picking speed. This person rode around after fitting the bulb and set the light to hit the road as far as it could distance wise on high beam as slightly left. Thats DOWN on the road as far as possible on hi beam done at night. He has never had any flashers from other people coming the other way,like you do if there too bright. And he doesn't use high beam during the day like some idiots do, occasionally low beam in really crap weather. Seems I know a lot of stuff about this person,just a coincidence. You want to see the brick on the road or the pot hole,dead Kangaroo,not parallel to the road and dissipating or shining in mid air or worse, up in the air .
  7. #7 oldcorollas, Apr 14, 2016
    Last edited: Apr 14, 2016
  8. O ok, not the 130./90 watt highly illegal ones then.
    • Dislike Dislike x 1
  9. nup.. those suckers pull some decent amps through stock wiring!
    the +130's nowadays are not thaaat different to the high current bulbs of yesteryear...
    there are some evaluations on sites like candlepower..

    60/55 is at a specific voltage.. at vehicle running voltage, they could be more like 75/70, but still technically legal
  10. Sounds to me as though you should change back to the recommended setting (as recommended),and then simply raise the front wheel 2-4" off the ground whilst riding for better vis. ;)

    Personally I know little about light adjustment, but it seems as though you've gone to some decent effort to ensure that not only is the light right for you - but that it's also not uncomfortable for oncoming motorists. Kudo's for that!
  11. I just go for a ride at night and move the light accordingly to suit what I want to see :eek: