Scooterotica

I'm just in the process of doing an H4 conversion at the moment which is basically the same as Coaster's, (just a little more radical with the surgery on the old bulb holder ).
Apart from getting a better light, one of my objectives (I have a SIP speedo, hydraulic brake hose and indicators attached to the headset) was to get a little more room in the headset.

First thing was to check the focal lengths of the old BA20 bulb and the new H4 to ensure a half decent beam pattern with a standard reflector/headlamp glass. This worked out quite well by removing the metal collar from the old bulb holder (a CEV type) and modifying and the H4 bulb like this:





This is how it now looks mounted in the reflector assembly:



I sliced off the back end of the original bulb holder and used JB Weld to glue it to the back of the H4 connector, so I could use the original spring clip fixing:



And this is how it fits:



Fortunately I had a spare broken bulb holder to butcher and play with allowing me to return to standard if this setup causes any problems.
It should be noted that I have dispensed with the useless side/parking light so it might not pass the UK MOT.
I'm hoping that my SIL 12v stator/BGM regulator has enough grunt to power the 55/60w bulb, but at least I have a BGM LED rear light to give it a fighting chance.
Today is final assembly day so I should see if anything shorts/melts/blows up very soon!

I've never had the sidelight checked at the MOT but to get the focal point /beam correct I took the headlight off the scoot and wired it up to a battery ,then moved the H4 bulb in and out 'till it gave a good beam on the shed wall.

Minority wrote:I'm hoping that my SIL 12v stator/BGM regulator has enough grunt to power the 55/60w bulb, but at least I have a BGM LED rear light to give it a fighting chance.

Mine has coped fine with just a standard SIL stator in the past although I have since re-wound the lighting coils to help with charging the battery.

Well I've just finished adding an H4 to my GP. The only struggle I had was when the switch was on dipped beam both filaments lit up, albeit dimly. I found this was my fault. I connected Red to Red, Blue to Blue and Yellow to Yellow (as you would). Except that wasn't correct. I looked up the H4 connections and I'd wired the earth up to the dipped beam wire and vice versa.
I connected a battery to the loom and checked all the lights. My only concern is the rear LED. It lights when the headlight is on but is a lot dimmer than with the headlight off, the brake light is also very dim, there's not much difference between the 2.
With the headlight off it lights up OK, quite a bit brighter. I haven't had time to start the scoot and try it that way, it's kept in my kitchen and a bit of a faff to get it in and out.

Went out for my first night ride with the H4 conversion and was pleased with the result.
Given the limitations of the original reflector and glass I have a nice bright light with reasonable beam pattern and a proper dip/mainbeam differentiation.

I'm currently doing this on my GP. In my block connector the red is the earth - according to all diagrams I have seen. So I have the blue and yellow on the block connected to the blue and red wires from the switch. I have spliced a wire from the red (earth) wire on the block and I have been plugging this into the black terminals on the bulb holder. My only issue is what wire plugs into that red earth wire. I have been trying either one of the 2 blacks from switch/loom. I have no headlight - only a taillight. What am I doing wrong?

Sorry for being thick

The bulb holder earth wire needs to go to a good earth on the headset not to any of the black wires, these are the feeds for the rear light and speedo bulb only.

What he said

I've spent the afternoon doing this to my Series 2 and couldn't figure it out until I did as wack said above, in fact, I earthed it to the earth for the sidelight and it works great.

I shall have to start charging