Screw mounted tail lights.

[Portis]

Can someone recommend a tail light that attaches to a bracket on a rear bike rack? I have a bag on the rack, and can't use the seat post as the bag blocks visibility from the rear.

[tsl]

Cat-Eye 1000/1100 mounts to a US-standard reflector bracket or similarly drilled rack. (Two holes, vertical orientation, ¾" on-center.)

Caution: The screw that ships with the light is too long. It intrudes into the battery compartment. Before mounting, with no batteries in the light, screw the screw all the way in, piercing the battery compartment. Remove screw, poke a thin knife or a file into the battery compartment to remove the plastic the screw pushed through, so the batteries will slide in and out nicely again. Then when mounting the light, use a washer or two to take up the extra space.

If your rack has two holes in a horizontal orientation 50mm or 80mm apart, that's the European standard. Try a B&M from The Touring Store (http://thetouringstore.com/BUSCH%20&%20MULLER/BUSCH%20MULLER%20HOME.htm).

[tsl]

Actually, the DiNotte mounts to a rack nicely too. Just wrap the O-ring around twice. The battery bag velcros anywhere on the rack. I have mine on the underside of a crossrail, resting on the fender.

It's shown here on my Tubus rack with the B&M taillight. I like the B&M because it has a huge built-in reflector (for legal compliance) and a low-battery indicator light.

[HardyWeinberg]

planet bike superflash (http://ecom1.planetbike.com/3034.html) has a rack-mount bracket (http://ecom1.planetbike.com/3108.html). The light should be <$20 at your fave e-vendor. Get the bracket from PB though.