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Headlights...why only one side is on?

Discussion in 'New Riders and Riding Tips' started by nosuchthing, Nov 8, 2005.

  1. Hi,

    I have a question which I'm not sure if its been asked before, but why do some motorbikes, eg R6, ZX-6R, have one side of the headlights on and not both?

    I know the side thats not on is for high beam, and that you ride with the headlights on all day, thus may drain the battery, but, it seems odd (and looks odd) not to have both sides on at the same time.

    Your thoughts?
  2. i agree mate,
    i've often wondered what the real reason is.
    perhaps in part it has just become a style of its own???
  3. "I'll call him ..... Blinky the motorbike!"
  4. Wasn't there a law somewhere (europe??? america??) that stated motorbikes could only have one headlight on at a time? Think the reason was that with 2 headlights on, car drivers would get confused and think it was a car from further away instead of a motorbike ....

  5. One is low beam one is high beam. That's my understanding of it anyway. Because they are 'Hard wired' on only one displays while they are riding around. When they switch to high beam both lights come on.

  6. Didn't it start with the Ducati 916?
    I remember that for a while they had to fit a single central headlight to comply with ADRs. Not beautiful.
  7. Found it .... European law:

    Pre-1997 motorcycles with double headlights are only allowed to have one light burning on the dim setting. Post-1997 motorcycles may have both lights burning. http://www.timberwoof.com/motorcycle/faq/europe.html
  8. Because they arn't Honda's :p :LOL: :LOL:
  9. Yeah I thought my bulb had blown when I first saw that and took mine back to the bike shop... :p

    I think it looks stupid and would much prefer to have both on

    Do Honda's have both on?
  10. nope but the 02 zx9r dose
  11. There's often also a technical reason behind it.
    The sum of consumers (lights/indicators/ignition/alarm systems/ blackbox/ABS etc etc) determine the output-rating of the alternator. The more output is needed (particularly on a permanent base), the more windings are needed. Copper windings need space and create weight.

    About 280Watts output are standard for a 600cc bike. It hardly leaves any headroom for accessories.
    The Strom has a lousy 360watts (and drives both headlights).
    Headroom for accessories is fairly minimal.
    The new BMW GS12 Adventure delivers a massive 760Watts output (permanent rating) in comparisson. It'll easily take a set of driving-lights/ GPS and have oodles left over for all sorts of gimmicks (until overdone and the the ABS-system crashes again due to lack of power-feed, the reason BMW came up with that new "powerplant" in the first place).
  12. I am sure the VFR has both on, the Yamaha FJR does for sure.
    Interesting why they do this, makes a bike look one sided at night. :LOL: :LOL:
  13. i know all CBRs with 2 headlights only have the 1 on with lowbeam
  14. The Sprint ST I used to have only had one light on low and two on high although a common mod was to alter the relays so both worked on low.
  15. Thanks for the reply peoples.

    I still think it's strange myself to only have one light on. Makes the bike look odd and normal car drivers probably think we haven't been stuffed to get the light fixed.
  16. Having both on would stop people telling me I have a headlight out :roll:
  17. perhaps its the same reason cars with 4 headlight globes only run 2 in low beam...
  18. The idea of only one low beam isn't exactly enthralling to me. As I live outside of Melbourne, my riding is on country roads where good headlights are essential. To have a low beam restricted to one light doesn't make the experience any more pleasurable. I'd rather max light visibility without dazzling oncoming drivers/riders.

    A lot of bikes that I've owned had terrible lights, so I used to strain the alternator friendship by mounting driving lights. When I had a Kawasaki ZZR1100 it had one globe in the headlight. A standard 45/35w it was, which I thought was criminal for a 280 km/h bike (even if you can only go at 100 kays). I wasn't game to go over 60 km/h at night. I put a 130/90 watter in it. It improved, but not by much. 100 km/h night time riding was marginal.

    The CBR1000 that I have now has two globes. Standard hi beam is 45 watters. I removed them and installed 60w Narva "plus 4" globes. Helped heaps but still not that flash.

    These days I avoid riding at night if I can help it, due to this very reason. If I'm gonna clout a roo or a wombat, I'd like the ability to at least having a go at avoiding it, by being able to see it...
  19. I get people regularly telling me one of my lights is out... A mate told me that an auto elec (or someone bike handy) can switch the assembly around so that one high beam globe exists on each side, and in turn the low beam. Sounds like a bit of mucking around though, doesn't bother me too much.
  20. my bike has the one headlight on and when i first got it, i used to hate its look and got sick of people telling me at traffic lights one of my globes was out! :x

    But it's just grown on me now and from what i've read online, the single globe in there is supposed to be brighter and more luminous due to the reflector design than the previous model. I've only ridden a few times at night and even on high beam the lighting's not all that confidence inspiring to follow the speed limits any higher than 60km/h.

    I think safety's taken a bit of a back seat in preference for 'following the latest fashion fad' in this case perhaps?