Has anyone fitted a 35/35 watt halogen headlamp bulb to their D14? Although these bulbs are available I'm concerned that the alternator may not supply enough current to cope with the extra wattage. Standard bulb is 24/24 watts. Any advice appreciated.
Is it 6 or 12 volts look up the alternator output then work from there.
Having checked you have 50 watts output with the ignition and charging you will be pushing the system. Go for 24 watt halogen bulb and led rear. You could change to 12 volt this will increase the wattage you can draw from the system.
Thanks for the info. I've managed to locate 6 volt 25/25 watt halogen headlamp bulb which will improve matters. Conversion to 12 volt would be a real pain, new alternator (no idea where from) rectifier, ignition coil, bulbs & battery (12 volt battery larger than the small 6 volt so modification to battery carrier to fit it) I'll stick with 6 volt as hardly ever used at night..
The D14 Wipac alternator is quite capable of sufficient output at 12v so no need for replacement. All that is required is a regulator/rectifier unit, 12v bulbs/coil/battery etc and a small amount of wiring re-adjustment.
The battery does not need to be as large as the 6v original as it will be properly regulated, in addition there are (expensive) reg/recs with a built in capacitor that could possibly allow running without a battery entirely.
Many thanks for the useful info. However, at 80 years of age I only use the bike in daylight so will stick with the 25/25 halogen bulbs so other road users can clearly see me.
More on this subject. Has anyone fitted a LED headlamp bulb in a D14 Bantam? My concern is that as an LED takes far less amps than a standard or halogen bulb the alternator may overcharge the battery with the headlight on. Normally m/cycle alternators only use 2 or 4 coils when only the ignition or sidelights are on and uses all 6 coils when the headlamp is on. If this is the case with a Bantam it could overcharge and boil the battery. I am not an motorcycle electrical expert so any expert advice appreciated.
Morning Alan l have d14/4 and totally recommend led lights you need to replace all including speedo light.
I junked the wico pacey set up with electix world system using a capacitor and no battery the bike needs a fair spin to start from cold but works fine and lights are better than bsa could ever have dreamed off.
As keeping original wipac system perhaps better to up grade to a modern voltage regulator.
Hope that's of help.
Just one other thing led lights are polarity sensitive
The switching in and out of coils from the alternator when the bikes were built was because that was the only cost effective (very rudimentary) regulation available at the time. Nowadays, regulator/rectifiers are relatively cheap and do a much better job with much simplified wiring.
My D14 , I converted the original wipac alternator to 12v and reg rec.
Worked well ,
I used a gammatronix unit that used the contact points.
All lights worked well with standard bulbs , I kept these original
Quote from: Y13 Alan G on 17 Dec, 2024, 10:26 More on this subject. Has anyone fitted a LED headlamp bulb in a D14 Bantam? My concern is that as an LED takes far less amps than a standard or halogen bulb the alternator may overcharge the battery with the headlight on. Normally m/cycle alternators only use 2 or 4 coils when only the ignition or sidelights are on and uses all 6 coils when the headlamp is on. If this is the case with a Bantam it could overcharge and boil the battery. I am not an motorcycle electrical expert so any expert advice appreciated.
Hi Alan I use Halogen bulbs in my scooter they are brilliant, got them off the internet from China, I think but they are very good.
TTJohn