id look into the lehner 1930 motors, or the neu 1509 motors. they are very lightweight, and super powerful, but you need the dough for those. they lahner goes for $238
here is a crt .5 with a lehner 1930
http://video.google.com/videoplay?do...arch&plindex=0
considering the crt .5 in the video was on 2s lipo, which is equivelant to a 6 cell nimh pack, that motor has power. weighing in at only 230 grams, its one of the lightest motors of that size available, considering the feigao L size motor weighs in at ~310 grams.
BTW, id go with a new crt .5 because if you buy used you dont know what the things already been through, like condition of the diffs, etc.
also, that 1930 would be insane on 4s lipo, check out this esc.
https://www.unitedhobbies.com/UNITED...idProduct=4691
if you use that esc, you will need a pistix adapter
http://www.rc-hydros.com/pistix.html
id personally go with this lipo, or something similar, (note the price)
https://www.unitedhobbies.com/UNITED...idProduct=4129
hell, ive seen lipo chargers for <5 cells go for $30 at
www.truerc.com
you can get the motor at
www.finedeisignrc.com
(chris fine is not the best dealer, so be CAREFUL!!)
god i hope this post was helpful.