The topic of the proper placement of a taillight can be a bit of a charged topic, believe it or not, in a group setting.
First of all, an avid enthusiast roadie (such as me, not to put too fine a point on it) knows the best way to be visible is not just to wear a bunch of neon green or yellow stuff (no offense, Tinkoff) when you’re on your bike. Now, after seeing a guy, barely seeing I should say, riding in a forest green jacket, possibly the worst color to wear on a bike, one must know the trick is to be loud and proud. Err… Anyway, bright red works great. Bright orange too… Yellows, even some of the blues – and white is a sure winner. Brown, gray, black (how I wish this weren’t so! I love black!), dark green… these are all bad. The additional trick, however, to really sticking out, is to look awesome. The more impressive one looks on a bike, the more you stick out. If you doubt me, you’d better check your awesome.
There are those times, however, where you just wanna wear black. For these days, I like to fly a light, just to make sure I give myself the best chance to pull into the driveway with the rubber the right side down. Also, while I absolutely will not ride in pea soup-thick fog, I will ride in less than perfectly clear conditions… For those days I want the brightest light I can get and the Serfas Thunderbolt is it.
My friends and I all use a Serfas Thunderbolt taillight. All of us. Rather than drone on about how bright it is, I’ll simply say this, a police officer once pulled over a friend of mine on his bike to compliment him on his choice of lights because the officer could “literally see [him] a mile away”. He had it on “low blink”.
It’s a bright frickin’ light.
Anyway, the normal placement for a taillight is either on the seat post or on the saddlebag, right?
Not if you use a Thunderbolt, you’ll blind the $#!+ out of anyone riding behind you.
This is the proper place for it in a group setting:
On the left seat stay, just above the dropout.
See, the norm for a group ride is not to look at the wheel but over the shoulder of the person in front of you and up the road, with maybe a glance down every now and again to make sure your wheel spacing is right… With a Thunderbolt on the seat post, even though it’ll be pointing down a little bit, it can be distracting at best, blinding in the worst cases.
Now, because you’ll be checking the wheel in front of you from time to time, the seat stay placement might seem worse, because it will shine up into one’s face, but it’s not. We all ride with our light there and we never have problems.
So please, think of the person on your wheel. Don’t blind them, dude.
If you like using a light, I would like to recommend the Thunderbolt. In my opinion, it’s the best bicycle taillight on the market, by a long shot. I bought mine, minus my club discount at the local bike shop, and Serfas has no idea that I’m giving their light a review.
Ride hard, my friends. Or ride your approximation of hard. That works too. Just ride.
UPDATE: My brother from another cycling mother, Titanium Henry chimed in down in the comments section to suggest going with the full-time on position rather than the blink to avoid blasting your brothers and sisters in chain rings with a strobe light show…
Fit Recovery 
This is great – thank you! A lot of my cycling is done home from work in the dark and so lights are really important – I hadn’t thought about the positioning at all (although less important as I am not riding in a group but I still don’t want to blind anyone behind me). Presumably in the UK it would be on the right-hand side, i.e. the side of the bike closest to the traffic? I’d be interested to hear your thoughts on front lights as well. Some of my cycling is on cycle paths where bikes coming in the opposite direction pass next to you and some riders have SUCH bright lights it is very unsociable. And I would claim not necessary when riding in a brightly lit city to have such bright front lights but am happy to be proved wrong!
I have a fairly bright headlight, but only because I use it once a year and only out in the middle of nowhere. The only light available is that coming from my headlight… Again, I stuck with Serfas, the True 350 USB Headlight. To avoid blinding oncoming traffic, including cars, I point it down a few degrees so the main beam shines about 10-12′ (3-4 meters) in front of me. I agree with your assessment, the ultra-bright 1200 lumen lights are only needed when riding single-track mountain bike trails. The 350 is priced intelligently and is good enough to ride by, but not ridiculous.
You’re also correct… That would be the right side for you.
And thank you kindly.
Painfully bright lights are illegal on-road in the UK (Road Vehicles Lighting Regs) but there’s little chance of police ever enforcing it. I agree that the right seat stay is a good place to put it. It has the advantage that it’s very easy to check it’s still working. There is a minimum height regulation but any bike with 26″ our bigger wheels will meet it… and see above about police.
Thanks for the clarification, MJ.
What do you recommend on the front?
I’ve got a Surfas True 350 USB… It’s not the brightest but it’s bright enough and it doesn’t cost an arm and a leg. I only use it once time a year. 😉
That placement doesn’t work pulling a BOB. It barely works to have it on my seat stay up higher. I know your discussion is about in a group ride and I understand the distinction. I have a PlanetBike on the BOB and a Cygo Hotshot on my seat post. My daughter says she can see me from 2 miles back. The problem with the Hotshot is that it doesn’t hold a charge as long as I’d like. I used it on my ride Sunday and it went out going to work yesterday.
I ride an gravel event called the Night Bison, a ride that traverse country roads and starts at sun down. All riders are instructed to put their tail lights on constant, not flash. Not only is it blinding at night with several hundred riders, but it will drive one (me) completely insane following a bunch of nuclear blast strength flashing tail lights for several hours in the dark!
That’s a very good point, brother. I think if you embraced your competitive, ass-kicker self a little more and got up on somebody’s wheel a little bit, you’d find that the blasts wouldn’t bother you quite as much because you’re looking beyond far enough that it won’t mess with you.
Still, interesting tip, amigo.
LOL — I actually do have that competitive component, but I have let it slide the past few years. It comes out now and then.
At night, the flash literally night blinds you, worse than the headlights from an approaching car.
I know you do, brother. I was just ribbin’ ya.
I love my serfas, (different model though) I run two of them at night, one on my back and one on my seat post or helmet. People tell me I look like a police car which is great for riding solo in winter…but yeah, I needed this post to remind me that if I ever ride with a group I will have to tone it down.