Thread revival alert.
Just realised that I actually started this one a few years ago!
This has always been a bit of a holy grail for K's.
I fitted a pair of HID bulbs to the GS last night and that's what has inspired me to impart my new found knowledge. My sight is nearly back to normal after looking into the lit headlight!
They are a pair of 50w 6000L H7 bulbs with slimline ballasts and an anti glare, dip bulb. Last bit is important.
Bought the kit second hand from a guy on the ukgs forum.
Did a bit of research first and it can be a bit of a minefield.
Firstly, the legislation. They are not illegal on bikes exactly. It's a gray area.
On cars they must have self leveling lamps and a washer. Bikes are not mentioned.
What they must be is, correctly adjusted, not cause glare and if more than one bulb, be the same colour.
Still on the legal thing, your 100w bulbs are illegal in the UK and probably many other countries, too. Anything over 55w is.
Many of the problems with fitting HID is that the, ahem, older person tends to go for China's finest because they are cheap. Been there, nearly done that.
These can cause glare and a thing called 'candleing' which means your headlight is scrap. Components are maybe not up to the motorcycle environment either.
HID is a popular mod on the GS and many have had them for years, passing the MOT without any problems.
The man to talk to is called Les Wassal, he's based in the UK and he runs a site called HID50.com. Very approachable if you want to ask stupid questions.
The main reason I'm sharing this is because he has a page on his site explaining why H4 bulbs are difficult to replace with HID. I've never found anyone else to give a satisfactory answer.
He claims to have found a working compromise for H4 lights and immediately I thought of all of you dinosaurs.
Can't put the link in from my iPad but look for the page 'What bulb'.
Tell him I sent you. Feel bad buying a second hand kit after enquiring about a new one!
It's as much about being seen as well as seeing. Was cut up on a roundabout twice yesterday. Once by the driver of a cattle truck eating his ice lolly and again by a teenager trying to grope his girlfriend as he enters the roundabout. It's a dangerous world out there.