Eyc headlight problem

sms wrote:
On 4/12/2021 1:59 PM, wrote:

snip

My bike had old halogen bulbs on PBP 2007. I believe one of those two
lights was a special series light so the dyno would send power to one of
the lights first and then only send power to the second after getting up
to speed. I think B&M or whoever made the lights specifically made
those second lights to use in that way. But with my newer B&M LED
lights I just wired them parallel. No one bothered to make that special
second light for LED because everyone thought LED was good enough with
just one bulb. No need for two lights with LED unlike with halogen
where the second bulb in series was kind of necessary. Equal full power
to both lights simultaneously. Now at lower speed both lights are weak.
But since LED lights up at fairly low speeds, it only takes about 7-8
mph to get both LED lit up to full brightness. So no real downside
because I never ride slow enough to not get both lights going full brightness.


In honor of Frank I decided to stick my 12V tire-driven dynamo light set
on my beater bike. Very classic. But awful. At first I thought that I
had some kind of wiring problem because the output sucked so bad.

I hooked up a small 12V SLA battery and it brightened up considerably so
apparently the dynamo was not putting out enough current, though the
unloaded voltage exceeded 20 volts. The drag with the lights connected
was unbearable.

Going to give up on that experiment.


Certainly if you want more power out of a bicycle dynamo system, you’re
going to have to put more power into it. I’m imagining the setup on my
buddy’s Fiat 124 Spyder in the late 70s. Bosch halogen headlights, plus a
set of Bosch driving lights with the 100W halogen bulbs. Turned night into
day, but sucked a good 300 W out of the battery. LEDs are a game changer,
but you probably still aren’t going to want to have the dynamo sucking more
than 5-10 W out of your efforts, which might get you 500-1000 lumens,
which, if you have decent optics, should be more than enough for nearly
anybody.