LS through a convex lense?

Has anyone tried focusing a LS (post collimator) through a lense, say from a cheap camera or something, to get a tighter beam - useful for something like...mountain biking! Would that even be feasible?
I've found the collimated beam to be bright, but not penetrating enough. What's the difference between the "new" and the "old" optics I hear people discussing?
Any suggestions would be helpful.
Thanks,
Dan

I have found that a 3/4" clear acrylic ball will give you a tightened beam on any of the LED's I've held it up to. I just tried it over a LS and and it formed a nice round even spot beam. With one of these balls as a lens, you can't believe the uniformity of light within the beam and at the edge, it just cuts off completely. Plastics stores like Tap Plastic sells these in 1/2", 3/4" and 1" diameters. I believe you can cut the balls in half and use a hemisphere for roughtly the same effect but then you have to polish the surface of the cut. These make a cheap replacable lens. They are so clear that I don't think the light loss is too much. A 3/4" ball held up to the ARC AAA will give you a perfect circular beam of about 30" in diameter from about 10' away. Don't know if it would work for your application but it's an inexpensive experiment.