Convoy M21D can sustain 1300LM for two hours.
If you need very powerful and very flood light Nightwatch NSX3 or NSX4 are that. For me best mountain bike light is my old Fenix BC30 which can sustain 1200lumens for over hour. My new favourite for biking are M21C and M21B with FC40. M21B 5000K FC40 have good balance between flood and throw. Also there is now M21B with XHP70.2 which will be also very floody. Best flood light which I have are NSX3 and Astrolux S43. For helmet light I think to try S21A with LH351D and TIR optic if I need more flood or throw.
I have experience with this. I used a D4SV2 W2 floody optics that’s giving me constant brightness and Anduril allows setting a higher temperature. I don’t like the W2 for biking because 5800k is not comfortable. I’ve switched to the Sofirn IF22A 4000k. This uses Anduril too so I set the temperature to 60c and it gives a very nice bright beam in high CRI. It’s USB-C rechargeable.
I tried the Sofirn IF22 (temp changing) and that’s not bright enough because of step down. I tried S2+ 219B 4500SW/3500SW and those are barely enough and I wouldn’t use it unless you are on familiar pavement road. However the 2 above are still better than 95% of what the biking community offers in terms of brightness.
- 900 lumens is needed because you are going fast and unlike cars which can absorb road impacts and water puddles. I also need other cars to notice me as if I am another car.
- You can 3D print a visor for it so the spill doesn’t blind cars and people opposite of you.
Flooder and mid thrower for the bar and a D25S on the helmet. The DQG Tiny 26650 v.1 projects further than my other TIR triples/quads (get to better utilize that battery size of which I don't otherwise have much use for). Btw, there's next to nothing on this light on BLF. It's a simple enough interface for biking.
The S21A can also be the flasher with all the mode options.
The D25S is great and is probably really all I need.