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[Dennis C]

Sorry I forgot to answer the original question, Fishermanfeg the current draw of LED daytime running lights is low enough not to worry you Bullet just connect them to a DC supply that is switched by the ignition.

[Adrian]

There's no reason why the AC output for the headlight couldn't be fed through a reg/rectifier unit of its own, with a built-in capacitor (Boyer single-phase Power Box or the Sparx SPX023). However, the Thunderbird alternator (except on E/S models) sacrifices one of its lighting coils to make way for a charging coil used for the CDI ignition. Of the remaining five coils, I'm not sure if it's 2 to power the feed to the rectifier for the DC system and 3 coils reserved for the AC headlamp supply, or whether it's 3 for the DC supply and 2 for the headlamp. I've not seen a breakdown anywhere of the power output for the uneven "halves" of these alternators







As the Thunderbird will need external day running lamps (no casquette, so you can't just replace the pilot bulbs with LED equivalents) it might just be easier to run a feed to them directly from the battery via a handlebar-mounted switch, and run the earth to the nearest convenient point on the frame. If the lamps aren't too big you could fit these in place of the front indicators where they are mounted on the Thunderbird's headlamp brackets, and move the indicators to the bottom fork yoke, otherwise handlebar-mounted types seem popular. A pair of brackets would be needed to re-fit the indicators, part nos. 801164 & 801165, as on the classic Bullets.



A.

[Scalyback]

I'm almost tempted to poet the Bally theory of operation (pinball machines)



Anyway, those displays in the 1980's with the vacuum tubes (like the green ones in battery hungry calculator before liquid crystal) use the eye refresh rate as Les H said.they also rely a little on the eye registering bright light in the same way that you get an after image if someone flashes a light in your eye.



out of the 8 digit displays, only one digit would be lit at a time, but the frequency meant that you did not see a flicker. with the 8 digit display, and also updating the score, the displays were only actually lit for 17% of the time!



SO?running led's on ac will use half the power, as they are only on half the time but have the same brightness. It's like running a film at 100 frames per second. you will only register about every fourth frame and the brightness will be the same!



Even better, get the bi polarity LED's which have full wave rectifiers in them. If nothing else, they will work on both positive and negative earth bikes.

Any comebacks and you willget the theory of bally operation and... I willbe asking questions afterwards!

[Dennis C]

As it is now over 10 years since I retired from electronics perhaps I am a bit out of date, so I have just been browsing my old mate Pete's website and can see that LEDs have moved on a long way, he is the man who currently knows and is now listing bipolar LEDs which can also be used on AC systems.

dynamoregulatorconversions.com

[fishermanferg]

once again thanks for your replies now that I think back my last bike a Honda cm custom 400 1980 I had led lights on that but I ran it from the battery with a separate fused switch just like adrain suggested maybe the best way I have just wired in two rear pilot lights with normal lights and the seem to work ok

[jefrs]

Dear Les - nothing that I said was incorrect. Learn to read, there's a good chap.



I've used LED for years. I am using LED on the bike and on the car. You can use LED to conserve power but their light output is not always better, on a couple of occasions I've have to switch back to normal bulbs, especially where a reflector is involved - LED are directional.

I've used LED on DC and AC systems. Used straight on AC you get less than half their full /light/ output, nothing to do with flashing (I did not even mention flashing), half the cycle at rms voltage (try 0.68/2=0.34 x rated output) - this may not be as much light as the normal incandescent bulb puts out. An LED will come on around 0.7V, rise in light output to peak voltage, dim whilst voltage falls and cut off about 0.7V, remain dark a while and then repeat the process. A two quid rectifier from Maplins will be low power, a proper bike rectifier costs a little bit more and now we're modifying the wiring loom (the expensive part, time and labour); I find that stuff easy but most run away screaming.



I've got LED pilots on the bike. When I replaced the tiger eyes I got less smidsys. Then when I replaced the sidelamp in the headlamp shell I got more smidsys, or maybe I'm just lucky. That LED does not illuminate the reflector, it just twinkles and points up in the air somewhere: DRL need to be aimed at the cars - I shall probably switch that one back.



Me, I just put the LED in and see if it works, see if it is better than the original bulb - not always.

[Bertie the Bullet]

WOW far to much info... As Dennis said, the Bullet will cope fine with LED's, I run with lights all the time and also heated grips, phone charger socket, just wire them into a suitable 12v supply, job done.

[Dennis C]

Scalyback, come on Bally theory of operation indeed?, what do the yanks know about pinballs and flashing light?.

[Scalyback]

[Dennis C]