@PiercingTheDarkness - we’re on the “same channel.” I’m thinking the same thing and now also want to do runtime with active cooling!
To add to the data points, unlike S21D which always seems to settle/level out at around 9-10 minutes, my M21B with GT-FC40 runtime curve levels out at 2 minutes, whereas M21B with B35AM settles at 15 min. Both lights have 12-group UI.
BTW, the BAM’s Tmax is the lowest of my Convoy’s, around 46° C at 12 min into the Turbo runtime, then it settles down to 42° C at 30 min once temp regulation kicks in. I’ve learned something more about Convoy temp regulation algorithm from this discussion. Very interesting.
I have some good news to add to the data points. I did a Turbo runtime with a cooling fan next to the S21D and it does make a difference. From 100% start, output dips to 46% at 10 minute mark (vs ~37% non cooled), then it actually started rising over next 20 minutes, to 53% at 30 min (non cooled never rose from 37%).
During the run, external temp at the head of flashlight hit a high of 54° C at 4 min, but subsequently cooled down to ~43° C the rest of the time. Non-cooled hit “Hi” on IR gun (meaning above 60° C) within first 5 minutes, and stayed there the rest of the run.
That is interesting, but in actual use it’s most likely still going to be stepping all the way down, unless used somewhere with cooler temps or it’s a windy night.
If the turbo is reset, without cooling, it responds as if on a timer every single reset.
Zeroair’s graph is strange though because if it’s a temp stepdown then how could that be at only 35.8°C unless his sensor is inaccurate. I’ve tested the same models in some of his reviews and even with a fan my recorded temps are much higher
1. Agreed 2. Agreed. I might have an answer; something I haven’t posted yet but basically my S21D hits a high by 3 minutes or so and stays high above 60 C for the next 30 min. That’s why it never recovers to be higher than 37% despite of the presence of temp regulation. As for the clock work leveling between 9 and 10 minutes, I agreed and have no idea why. Maybe the algorithm is: once T=55 C, decreased to x output over next 7 minutes and stays there? 3. Agreed. I have the Rowenta fan on Turbo mode right next to the flashlight. Don’t know how he got 35.8° C.
Does anyone know if I can use a OP reflector in my C8+ with W1?
First I wonder if it will creat a nice beam or not, but ive also noticed that the hole diameters are different between the smooth and OP reflectors. With smooth being 9mm and OP being 7mm.
Would I just need to make sure to ask for the correct centering gasket?
I have 7 and 9mm paired with Osram W1's and 7mm has tight and concentrated hotspot where 9mm has corona and needs some adjustment, adding some spacer to lift reflector more up. It is not focused properly at all this option
Im not sure I fully follow you.
I currently have a C8+ with W1 (green) and smooth reflector. Hole diameter unknown.
I want to try an OP reflector to see if I like how it changes the beam.
Looking at Convoys Ali Store, there are two listings. One for the 9mm Smooth Reflector, and one for the 7mm OP Reflector.
This leads me to believe that my current smooth reflector must be 9mm. The OP Reflector I’m looking to replace it with is only available as 7mm though.
I don’t understand why the Smooth vs OP have different sized holes.
Does anyone have experience with s2+ 519a using 5 degree flat and 10 degree bead tir? Are they more throwy than orange peel reflector? Any rings/artifacts?
or any other 26800 lights 
