I want to purchase a new rear light for my bike. I only ride in daylight. Therefore I will be using the blinking mode. The light will be installed on the seatstays. The bag takes up too much room on the seatpost. Some of the reviews state that it is blindingly bright.
https://www.amazon.com/dp/B07YFF4857...v_ov_lig_dp_it

Don't Spend any $$ Until you see the light in Person.
I have Been Burned by others that said the light is Great.

Another rider was looking for a new tail light last fall. I informally reviewed most of the bright tail lights -- run times, mounting method, etc. The only one I could recommend was the Cygolite.

Ha, those amazon reviews are extreme. The mounting bracket is sturdy and reliable, I have no idea how people are breaking theirs or losing their light. How?!

Get the 200 or the 150.
I have the Hotshot 150, and really like it. A 200 lumen light will appear to be a bit brighter, but not 25% brighter than 150. Vision is similar to hearing, where sound has to double to be just 6 db louder.

The 150 has a noticeably brighter beam than my old Hotshot 2W, and it's also spread out more than the 2W, so aiming isn't critical.


My only complaint is the Cygolite USB rubber plugs, used on most of their current headlights and taillights. These are a bit annoying to plug back in, and seem to fall out occasionally, hanging down from the light. I cut a "rubber band" from an old inner tube, and it fits around the outside of the tail light to help hold the plug in place. That works. (perhaps a piece of electrical tape would work.)

It's a great daytime light! It's visible even in noon sunlight, and really eye catching in sun+shade conditions. Other riders in my group were way ahead on the road, perhaps a quarter mile away. Their blink instantly caught my eye. I want drivers to notice me when they are far back, so they have time to react.

I run the single flash mode, which is a short, sharp full power flash. The other flash modes aren't as effective in the daytime, I think.
The other control button changes the speed of the flash. I have it set to 2 flashes per second, and this mode lasts a long time. I'm guessing 15+ hours? This single flash mode has the best battery life, too.

At night
The flash is too bright at night for a group ride! Way too bright for riders behind me. I switch it to steady mode, and then the second button dials down the intensity. When riding solo when it's dark, I use the "waa-waa" flash, which ramps the brightness up and down. Less annoying to drivers, and distinctive.

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The seatpost hard mount works great, easy and secure. Another rider has the supplied smaller size mount on the seat stay, and that works fine. He has round seat stays. Some bikes have oddly shaped stays, which might not work as well?

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Headlight too
I have the Cygolite Dash 520 headlight. It's perfect for me.
The rubber stretch band works with the under-bar-tape brake cables, and allows the light to be pointed up or down as I ride. Hard mounts for handlebars are really annoying to fit on.
The flash mode lasts about 9 hours (per cygolite) and I run it all the time during the day.
The 520 lumens is good if I'm still out after dark, but the full power only lasts an hour. (the half and quarter power are usable, and last 2 or 4 hours, approx.)
It has a low power flash or steady mode from 4 non-directional supplelmental LEDS. I rarely use these, but they would be nice on a bike trail to warn oncoming users without blinding them.

Thank you very much for your informative reply. After this purchase, I will concentrate on purchasing a front light.

Can anyone testify to what it's like to follow the 150 lumen light? I want to be seen by drivers, but I don't want to hurt the eyes of riders who follow me, especially since most who do catch up with me, so the light gets brighter and brighter as they ride.

if secured & positioned respectfully, no. I would rather you display a very bright light than to have a near wth encounter.

I agree that light is too bright for a fellow cyclist riding on your wheel. But if you ride solo, it’s fine.

I just bought that light last week but I haven't been out with it yet. I don't do group rides very often but if I do I'll just change the setting to steady or the "waa-waa" flash rm -rf mentions. Rapid flash is annoying in group rides even with dimmer lights.

Can A Light Be Too Bright? Yes it can, but more is the position of the light itself. One night I was driving in downtown Austin and had a very, very bright handlebar mounted light shinning right in my eyes from a bicycle coming from the other direction. I am not sure if it was intentional but it did in fact leave me momentarily blinded as it flashed by.

Garmin's radar is an excellent tail light.

Thanks for your responses. If I turned the light on when I was with a group, I imagine I'd turn it off pretty quickly, thanks to comments from other riders.

No.