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Headlights .. this time ..

Posted: Sat Apr 10, 2021 10:51 am
by Taid
Because I planned various bits of electronic gubbery I converted the 350 to 12v Neg Earth ..

The original scheme was to use the original dynamo with a DVR2 so I have fitted LED lamps all round but in the end I have fitted a 12v 100W Alternator, so have the power for a filament bulb.

I don't specifically plan a lot of night riding, but who knows how the future will run. I am not sure that an LED headlight gives the best beam pattern so am wondering about a Halogen BPF replacement, but again, beam pattern bothers me. The original bulb has its filaments lateral to the bike, but all the halogen bulbs seem to have their filament along the fore/aft axis. The reflector and lens of the headlight unit were designed for the original construction so should I need to get a new unit designed for the halogen bulb

Re: Headlights .. this time ..

Posted: Sat Apr 10, 2021 11:25 am
by Reynard24
I have converted all my alternator bikes to quadoptic reflectors for use with an H4 halogen bulb. I believe the club sells these and they do give a much better beam pattern than a halogen BPF bulb in the original reflectors. If you have the space, I think the 1955 headlamp is too cluttered, you can use a Neolite reflector which is better still.

Re: Headlights .. this time ..

Posted: Sat Apr 10, 2021 1:06 pm
by Taid
Thank you R .. certainly looking into that .. of course, the lens is a different pattern, but probably only a rivet counter would notice, and it's not a show bike anyway ..

Re: Headlights .. this time ..

Posted: Mon Apr 19, 2021 7:51 am
by g5wqian
i use a lucas TVS 7" headlight and a bpf led bulb in 6v on my ajs mod30 , all works well and good beam pattern .

previously i had an unknown headlight unit and same led bulb , dip beam was ok but it put the main beam up into the trees , but with the lucas TVS [sold in red boxes] the light goes on the ground in front of me .

it works ok with orignal bpf filament bulb also , so i see no reason it wont work with a halogen bpf bulb as well .

obviously a modern H4 headlamp may produce better pattern etc if you want to go that way .

one thing i would say for 12v conversion and halogen is to check the voltage at end of wire to the bulb holder to make sure you dont have a voltage drop from the thickness of the wire used , on my landrover the wire seems resistive and i had only 11v instead of 14v [when alternator running] so i changed the wires and got much brighter lights even with a standard 55w halogen bulb .
leds dont seem to suffer this fate though .

check out these also , i use them on my landrover , clear lens with shaped reflector .

https://www.ebay.co.uk/itm/Classic-Mini ... 101224.m-1

regards
ian

Re: Headlights .. this time ..

Posted: Mon Apr 19, 2021 5:22 pm
by MATT
All my bikes are 12volt so that I could use a halogen lamp, initially I put one in with a lucas fitting from Paul Goff but was a tad disappointed with the main beam which was far too spread out, it showed up the top of the trees a treat! I then installed a wipac head light unit which has the standard halogen fitment, the difference was great, a nice cut off with no tree top illumination. If you do go down that route just make sure it is a left hand dip as the first one I bought at a jumble was not -- sob!
Matt.

Re: Headlights .. this time ..

Posted: Mon Apr 19, 2021 5:38 pm
by SPRIDDLER
MATT wrote: Mon Apr 19, 2021 5:22 pm I put one in with a lucas fitting from Paul Goff but....... the main beam which was far too spread out, it showed up the top of the trees a treat!
LED-lamp Final (640x475).jpg

Re: Headlights .. this time ..

Posted: Mon Apr 19, 2021 6:14 pm
by Duncan
If you plan on changing your reflector consider how deep the back is with a bulb fitted as this can be a limitation in the three piece headlamp, the current Quadopitics are okay as are the replica and some pattern Lucas, I think the early plastic bodied Quadoptics are tight which is a shame as they give a good light and beam pattern.

If you want a low current demand there are LED H4 bulbs (look for the ones with a half shield over one or the LEDs in the bulb) that give a useable beam pattern but are not as good as halogen.

Re: Headlights .. this time ..

Posted: Mon Apr 19, 2021 8:14 pm
by 56G80S
I've bookmarked this thread as I stuck with 6 volt for a long time but now plan to cut the wire on the AO II unit. I do little city riding and although I have the measly 42w (!) dynamo plan to fit an H4 unit. The comment about "resistive wire" is really helpful. My experience with LED headlight bulbs was poor but the rest of the Matchless will be LED and therefore may have scope for improvements at the headlight.

Thanks for the information.

JohnnyB

Re: Headlights .. this time ..

Posted: Mon Apr 19, 2021 11:34 pm
by Taid
If 'cut the wire on the AO II unit' means 'convert to 12v' .. I understand that although your voltage may be higher, you will get even less power from the dynamo .. put simply, the field coil, intended for 6v, with 12v across it will use twice the current, ie 4 times the power compared to running at 6v .. I was told that the dynamo will only produce (I think) about 30 Watts of usable power, which is why I eventually fitted a 12v alternator ... and am fitting a quadoptic and e4 bulb (yet to be used in anger)

Re: Headlights .. this time ..

Posted: Tue Apr 20, 2021 8:00 am
by Mick D
56G80S wrote: Mon Apr 19, 2021 8:14 pm The comment about "resistive wire" is really helpful.
Hi

If you are using 'standard' period wiring at 6V on your bike, ie 28/0.30mm x 2mm sq there should be no resistance issues when switching to 12V. If you see a significant voltage drop it will be down to poor connection(s).

Theoretically you can half the cross sectional area of the conductor when doubling the voltage with no ill effect.

Regards Mick