Headlights using conventional bulbs (should) have the reflector/lens/shroud designed for the light coming from the small area of the bulb filament, LED H1 and H4 bulbs have a far larger area as the light source so you will probably find the beam pattern will be terrible and there will be a lot of light scatter to places you don't want it such as the sky or 5 foot in front of the bike. It will probably fail an MOT for not having the proper dip beam pattern but you could always put conventional bulbs in for the MOT.
Yamaha made a bit of a mess with the headlight design but I doubt LED bulbs will be any improvement
So i'd be wasting my money using LED's then
Okie dokie, back to the drawing board then. I think I might just customise an LED lamp/torch thing I've got and wire it to the main battery with an extra switch on the handle bars, just to get me through the darker winter mornings.
It's a pain in the arse as I only need it for half my journey to work as when I get into the town there is plenty of street lighting, but I've nearly crashed into the trees a few times on the first half due bendy country roads, pitch black, wild animals and no road markings to use as road position markers
