Looking for a source of a 12v MR-16 bulb with excellent color rendition

Planning a high beam for a bike light system. Will only be used when flying downhill. Probably a 15 degree beam would be good. Something around 15-20 watts. Probably drive it with 4 LiIons, so 14.8 volts. That should get a good efficiency but still have good bulb life, right?

Thanks for any info. I haven't looked into incans in a while.

these might be what you are looking for

http://www.solux.net/?gclid=CNSbrv6O34oCFQbpYgodIBr02g

any halogen MR-16 rated for 12V and 2000 hours life should perk up reasonably well at ~14V. won't be pushing the edge, but should be nice output with a good margin of reliability(50+ hours life I would expect). If you plan on running 4xLi-Ion stay away from bulbs rated for 5000+ hours because they will actually just be dimmer, but last longer.

The Solux lamps in the link above may be too much power...like you said, a 15-20W would be more ideal... and I have no idea how they come up with a 5000K bulb... They "claim" that the 5000K bulb is a 10V bulb overdriven to 12V to achieve 5000K with a 500 hour life.... which doesn't work the way we know bulbs (a tungsten filament won't give much better than around 3500K before "POOF", and that's with only about an hour expected life, if that)