Rear Safety Light for Bikes with Larger Seatpost/ QR PR5

I am new to the forum. I have a QR PR5 with the aero seat post. I have shopped around and not been able to find a rear safety light with a strap that is long enough to accommodate the seat post. QR sells the aero box but my 2015 will not accept it and the light seems small. Has anyone addressed this on their bikes? Thanks in advance for the input.

Buy this https://www.specialized.com/us/en/accessories/stixcomptaillight/106131 or this https://www.specialized.com/us/en/accessories/lights/stix-sport-tail-light/106132

and the aero seatpost strap https://www.specialized.com/us/en/equipment/accessories/stix-aero-strap-mount/117244
.

http://forum.slowtwitch.com/forum/?post=6233035#p6233035
.

Another option is to use the Dinotte adapter, which basically gives you a section of round post to attach lights to: http://store.dinottelighting.com/spare-parts-for-taillight-mount-kit-p49.aspx

The PVC pipe trick works okay as well. Dinotte’s taillights are THE best, without question. Anything that’s less than 100lm is simply not worth it.

For my Specialized Transition and now Shiv, I bought this:

http://www.lightandmotion.com/choose-your-light/vis-180/vis-180-silver-moon

along with this for the aero post:
http://www.lightandmotion.com/accessories/adapters/vis-180-aero-post-pad

Only with the light had a better blinking option. It’s bright, but it just slowly oscilates between super bright and less bright.
Seems less visible to me.
But I keep it due to it fitting so well

https://www.amazon.com/Serfas-CP-R4-Thunderbolt-Headlight-Taillight/dp/B00OPHF0XG/ref=sr_1_2?ie=UTF8&qid=1488997070&sr=8-2&keywords=serfas+light

I have something similar to this and I just strap it to the back of my helmet rather than the bike
.

NiteRider Solas comes in a 150 lumen version and has a rubber strap that fits the post of my P2 (which looks a lot like the post of your PR5).

https://seesense.cc/

250 lumens for the rear, 420 lumens in the front with the Icon + models.

It comes with a number of straps, one of which is quite long.

I use the Moon Shield it comes with an aero seat post mount.
http://www.moon-sport.com/...uct-detail.php?id=11

http://www.moon-sport.com/gimg.php?size=583x373&location=/file/product/product_main201.png

I use the Moon Shield it comes with an aero seat post mount.
http://www.moon-sport.com/...uct-detail.php?id=11

http://www.moon-sport.com/gimg.php?size=583x373&location=/file/product/product_main201.png

Thank you everyone for the great suggestions.

What pvc trick? Any pics

What pvc trick? Any pics

http://forum.slowtwitch.com/forum/?post=6233035#p6233035

Did something similar to this but basically just cut off t pvc pipe almost right down the middle for my seat post. Works well and doesn’t slide around side to side.

If the strap’s not long enough, you just need to loop an O ring through it to extend it. Go to my pic in this thread

http://forum.slowtwitch.com/gforum.cgi?post=4532426;search_string=nickag%20o%20ring;#4532426

You can loop as many O rings together as you need to make it longer.

The link that Mickison gave you.

That Serfa tail light fits perfectly behind the PRfive seat post. And, the elastic bands wrap all the way around without any problems. The thing fits so well that it almost looks like part of the frame/seatpost straight out of the factory.

I have the QR Box on a 2015 PRsix but I don’t use the box’s light. I prefer the Serfa because it fits so well and it’s so bright.