Ooooh, you're lucky it didn't smoke. The L1 head has no electronics. If you stick that on a 2x123 body, you're in serious direct drive mode, my friend. The regulator in the L1 is in the body of the light. Guess if you smoked it, you can upgrade to a high dome L1 /ubbthreads/images/graemlins/grin.gif
Mr Bulk,
The L1's tailcap has a resistor that probably wouldn't survive extended periods of running in the L4. It will run but you're most likely exceeding the power rating of the resistor. I know, I know. I too am in search of that dimmable L4. Haven't found it yet. Actually, I haven't had the time to pursue it. It can be done.
CM