On 2/12/2018 5:00 AM, Sepp Ruf wrote:

No, Joerg is claiming that ordinary StVZO tail lights that are visible from
500 meters in Europe are not good enough for his and fellow Californians'
impaired sense of vision, and why he feels tail lights that feature 5000 ft+
visibility are preferable. And he is trying to confuse what can actually be
powered by dynamo with what he "remembers" seeing, back then, on inspecified
cycles in traffic.

The StVZO lights are woefully inadequate. Don't forget that you need one
that is visible in the daytime as well. You don't need a 1500 lumen tail
light, but many are ridiculously weak, 10 lumens, or even less.

One that looks reasonable is
https://www.lezyne.com/product-led-sport-laserdrive.php with flash
modes up to 250 lumens for daytime flash mode. But I don't see a way to
mount it to a rear rack.