I'm getting a Magicshine clone with a red lens to use as a taillight. Basically I have an 8" length of 1/2" pvc pipe rigidly zip-tied to the back of my saddle and the lamp will use its O-ring mount on this little pipe. It would be much more convenient to my setup if I could attach it upside down. My concern is that there is only one screw holding the lamp to the mount; and since it will be upside down, that screw will have to support the weight of the lamp in addition to its other duties. I'm sure the weak link is going to be those few threads in the aluminum shell of the lamp. Possibly I could reinforce the setup with a ziptie attaching the lamp to the mount, but the heat of the lamp would probably melt the ziptie. Possibly I could wire the lamp to the mount sorta like a fireproof ziptie. Possibly I could permanently attach the mount to the lamp with glue or epoxy or some such (I'm not really familiar with bonding agents). How would YOU do it? Thanks for your help.

Wow, that's going to a bright tail light.

The Red Lens is plastic and knocks down 50% of the brightness.
I drilled 5 very small hole in the lens to make it brighter.

Mine is upside-down on my handlebars, and I haven't been that concerned about it. It might be a good idea to reinforce the mounting somehow, just in case.

I have a feeling that something could be done with the plastic mounting, without being too affected by the heat. Mine doesn't get all that hot honestly, and I have the spare length of power cable wrapped around the base of the light. No ill effects so far.

At least. A red lens over a white light make the light red by blocking all other wavelengths (colors). Red LEDs, on the other hand, only put out red light so they're much more efficient for the purpose.

The forces that screw will have to endure due to road bumps, potholes, and general vibration will be far higher than the static weight of the light. If it can withstand the former, I wouldn't be concerned about the latter.

Interesting information! Actually I already have one Magicshine taillight (which I guess uses red LED???) I'm going to mount the headlight with red lens side-by side with the taillight and then walk about a half mile down the road and compare the two for brightness. If the red-lensed clone doesn't do the trick, I will probably try the idea of drilling a few small holes in the red lens. Seems like it would crack or something . . . we'll see . . .Thanks!

You don't have to walk that far. The plastic is tough. Won't crack with a sharp very small drill bit.

Check the cable hole underneath to see if its watertight.
You might find swapping out the white LED for a red one will be just as bright on low. But will likely cook on high.

I think this would be beyond my capabilities. But I am curious--What do you mean by it would "cook"?

MS and the assorted clones usually run at just over 2A (the XML LEDs are rated at 3A but they all run at 2/3rds of this, probably helps when you have poor wiring, no thermal paste, crappy batteries etc). Red leds like listed below max at 1A.

SingFire Cree XP-E R2-N4 180lm Red Light LED Emitte On 16mm Star - Free Shipping - DealExtreme

Thanks for the info--