Search:

go fit some LED's it will be fine.

whats the bike?? usually the problems arise with farm bikes that dont have any smooth DC, now the good old incandescent light is just a bit of glowing wire and isnt too fussy, LED and discharge tube...

also dont use an LED unit on a bike that has no regulator/battery set up. they get really annoyed when hit with uneven DC

one of these would be the go, think 20% off this weekend too...

dontr use the jaycar ones they leak water in heavy rain let along river crossing, same with the supercheap ones