AJS & Matchless Owners Club

Got a great led bulb, Neville! Good dip and main and is like a search light! The downside is after only about 10 hours use the main beam either flashes or goes out.another £10 wasted, back to the quartz halogen

alanjennings wrote:Got a great led bulb, Neville! Good dip and main and is like a search light! The downside is after only about 10 hours use the main beam either flashes or goes out.another £10 wasted, back to the quartz halogen

Not an electrician but I am thinking the low current drawn by the LED bulb means the connection needs to be scrupulously clean. Have had the same problem with my LED headlight bulb and a clean of the connections has sorted it. By contrast the rear stoplight seems to remain, on at very low power and only just visible when the switch (mounted low by the wheel) gets either oil or water on it.

Cheers Clive! Tried it directly on a battery- same result!

Based on earlier comments in this thread about a dynamo needing a load to function, would LED head and tail lights give enough load? Just wondering...

Cheers,

Malcolm

No it doesn't need a load to function. It will only generate enough power to satisfy the demand of the lights and the battery. A multimeter will only tell you the voltage, not how much current the dynamo will produce as there is no electrical load. A weak dynamo will give a satisfactory voltage reading on the meter but will not be able to supply the current necessary for the lights.
The output of the dynamo is regulated by the regulator (!) which is a kind of seesaw with the bike's electrical demand (circuits and battery) on one side and the dynamo output on the other. When the electrical demand becomes heavier (or the battery needs some charge) the regulator increases the dynamo's output until the two are in balance - i.e. resulting in a 'zero' reading on the ammeter (e.g. no current flowing in or out of the battery as the dynamo is providing precisely all the electrical power that's needed in the circuits at that time - no more, no less (hopefully).
The bike's ammeter only tells you how much current (amps) is flowing into or out of the battery at that precise moment.

Malcolm

I'd reinforce the advice about connections and although you've probably done this I personally run an earth wire from the battery to the headlight, rearlight and each of the indicators (retrofitted).

I haven't had Alan's failure problem nor the rear light problem with my LED set up but..................

I have gone back to the Quartz Halogen bulb as the beam pattern is better and the light seems to give more defintion than the powerful but flattening light I seem to get with my 6 volt system.

As an aside, now I've finished the oil changes and tidying up the indicator wiring (and they still work, also LEDs) I'm going to fit an auxilliary lamp in the foremost hole previously used for the front number plate. I plan to focus it to provide a better indication of the nearside of the road. It's 12 volt but I bought a step up transformer and separate switch; fitting a 6 volt relay to operate the 6 volt switch and turn on the 12 volt light is beyond my electrical "skills".

I've got a second one of these lamps and may fit it in the rearmost of the front mudguard numberplate holes with a spacer to raise it above the other lamp; household tap washers are great for this as they are tough, provide some vibration resistance but don't degrade easily.

Johnny B