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Where do you attach yours? I have a dropper post and a small saddle bag. Therefore the only option appears to be on the collar of the dropper. This is below the top of the wheel though and therefore affects the light quite badly. Am I missing somewhere blatantly obvious to attach a light?
It’s an Exposure TraceR if that makes any difference. I was going to attach to the body of the dropper, but had possibly unfounded concerns over wear. Suppose I could ditch the saddle bag and attach to the saddle rail, but I got the bag so I could avoid a backpack
I use a Trace-R on the road bike just below the seat collar When I use a big saddle bag, but on the MTB (and for a bit more visibility when commuting in heavy traffic) I use a seat stay mounted Moon Nebula.
Exposure do a saddle mount for the Tracer. You might be able to squeeze it in between your saddle & saddle bag depending on size of bag/fitment type etc...
Have you got a helmet mount or a way to attach it to your helmet?
Turn it upside down (so it still points straight back) and mount it to the top of the RH seatstay. You might have to pad the stay out a bit with rubber - a bit of old inner tube wrapped round it works well. Should sit just to the upper right side of the wheel so it'll still be nicely visible from a driver's perspective.
Thanks all, crazy-legs has the best fix for me I think. Not buying another light as I don’t have the cash, my saddle bag is flush with the seat and no helmet fixing either.

Homebrew Bar end folding light mount.
I've found drivers are often a lot more considerate when I have a helmet mounted light.
No idea why, perhaps because they don't recognise I'm a cyclist or think I'm a horse rider until up close.