For a lightweight option, an Ultrafire C3, Trustfire R5-A3 or a Uniquefire G10 with an XP-G R5 emitter will give you decent throw and flood - runtimes are good on AA but not so good on 14500 li-ions (its easy to carry 2 or 3 spare batteries though - I do) - (I use two C3's on my helmet) - if you want more output and a floodier beam again, go for a Fandyfire 2160 or a 501b with an XM-L T6 emitter, or for ultralightweight, something like a Xeno E03 XM-L T6.
To use the Princeton headlamp, the first click turns on the low red light, the second click turns on the high red light. There is no flashlight. You have to hold down to get the white light. You don't have to go through a bunch of modes every time I've been looking for a headlamp like this for a while and I liked it so much that I bought a second one.
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You can get the magicshine bike lights with a headband - I guess thats what you need.
http://www.alpkit.com/gamma
absolutely brilliant for the price. probably not bright enough for use on the bike though.