I made a mount for mine, one halfords bike computer mount that cantilievers the computer over the stem from the bars and the seat post clamp from an old rear light that fitted the torch body. Bolted together and with a cable tie for security it's more than solid enough.
I have learned that if you make a jury rigged mount too solid it shakes the light to bit's, it needs a fair bit of spring in it, the metal body of the torch against the bars even with a bit of tube around it is going to break the solder on the circuit board or even break the LED off inside the housing.
I'm interested and surprised by this. I use Tescos all the time, but my mainstay is a Hope 1-LEd. The tescos have survived, but I do tend to use them just as helmet lights where they're protected from vibration by a combination of hi-tech polystyrene and my spongy brains.
I guess that either the "waffer-thin" rubber bits on the hope 1 mount, or something in their internal construction must guard them against this fate There's definitely not much spring in it.
Either that or your Tesco torch must've been unlucky
... I did attach a Tesco 2xAA torch for a 40 miler using a seatpost reflector mount and a jubilee clip ( not much sprig in that mount!) and it survived fine (and is still fine after several more journeys).
