Upvote:3
It will vary a bit depending on the aircraft version, but in general, the overhead bins on the CRJ-700/705/900 series (I've flown on all three) are quite small and will not accept carry-on bags that would fit in the overhead bin of larger aircraft like A320/B737.
I would either take your smaller bag, or just check a bag and then you don't have to worry about it.