Traditional cantilever brakes can pose a special problem when trying to mount a headlight at the fork crown. For very lightweight headlights made mostly of plastic, like many of the Busch & Mller headlights, the standard Busch & Mller cantilever mount will be strong enough, at least if you're using fairly large tires at low pressure. But many people are using 90PSI tires, which pass a lot of vibration through the fork and that vibration can lead to metal fatigue and failure of the mount. This new mount from Robin Thorn can solve the breakage problem, as long as your front brake is set up with a high enough yoke. Look at the fork from the front. If the hole in the fork crown is below the yoke, this mount will work.
If you use a Schmidt E6 or Edelux headlight, and if you use a wired taillight, you shouldn't use this mount. The slot is 10mm wide and there's not enough space for the taillight ground wire to connect.
See Peter White's Installation Page for moreinfo...(will open in new window)