I don't see why that wouldn't hurt as long as your rims can take that skinny of a tire. I have huge wide hybrid tires on my bike right now, but next week I'm slapping some skinnier slicks on it. Lookin' to gain at least a little speed.
Probably wouldn't hurt to dump that suspension fork too. They eat up alot of pedaling effort that could be transferred to your rear wheel when you really stomp on it.