Rear Light Woes.

[Sheffield_Tiger]

An alternative is to wear a light - but one designed for wearing, not clipping on a bike light that then flops down or gets covered

The Oxford X4 is pretty good at what it does - on a pack or on a back
http://www.towsure.com/oxford-pro-commuter-x4-fibre-optic-rechargeable-rear-light

But...obviously if you ride in a more horizontal position, then it's still more use as a landing light..

 

[flake99please]

I use a couple of Cateye X rear lights on either side of my seat stays. They sit just above the rear cassette.

http://vid16.photobucket.com/albums...bile Uploads/2015-10/IMG_2712_zpsojt6z0hr.mp4

 

[Sheffield_Tiger]

Another thing I've done is to take a pair of those wrist/ankle bands with the red LED's, and cable tie those to the seat stays.

Works well as a secondary light

 

[Wobbly John]

In reply to the OP, If your frame is big enough, you could fit a light to the seat tube of the frame, so that it shines out between the seat stays above the brake bridge. I've got 2 lamps doing this on my 23" frame.

 

[chriswoody]

You could always attach a light to the saddle rails as well. On my folder I don't have a rack so it was the only practical alternative. Cateye conveniently make one which then let's you attach any of their lights. Sadly in Germany many of their lights are not legal and so impossible to get hold of. (Try to buy on line from popular shops and they refuse to send them here!) So I've got an Exposure Tracer light which also has a seat rail adapter, though you need to buy it separately. A seriously bright light and thankfully legal here.

 

[ufkacbln]

Treat it like a handlebar!

There are a number of handlebar extenders like this one from Topeak

They adjust to fit a range of handlebar sizes so seatpost is no issue

You can fit them with the bar horizontally or vertically as you wish

It is possible to fit this, angle the silver rod down and have a pair of rear seatpost mounting lights below the seatbag