AH, emzed.. I have been down this road before and have only found opinions and no definitive answer. I will carry on looking myself too but please let me know if you find an official answer (i.e. from a test manual).
I am positive you don't need lights on a bike before lighting time, you would need a horn, but before the 3 years before an MOT how can you be judged?
I will make enquires and get back to you on that one........
There is no definitive evidence that lights on/fluorescent jackets/ sam brownes or any other "daytime conspicuity aid" has any impact on accident rates. There is some evidence to show that in low sun conditions, spring and autumn at dawn and dusk headlights can actually increase accident rates but the effect is marginal and it is a special case.
I usually ride with sidelights on as I have a pair of 2 watt Leds for sidelight bulbs, they show an intense point of very white light that is quite noticeable as a point source, I also assume that no one has seen me and expect them to pull out in front of me, move out without looking etc.
![Have you got your lights on? (2) - Forums [Biker Match]](/images/backgrounds/strips/8mobileLQ.jpg)
![Have you got your lights on? (2) - Forums [Biker Match]](/images/backgrounds/strips/8desktopLQ.jpg)
