i made the same swap on my ported shee, well, my rear sprocket is stock, im not sure if 41 is stock, i forget. it made a huge diffrence, i think it was all positive. i now am able to take advantage of the power i have, it pulls much more than the 13 did, the 13 would wind out to quick. you will have to shift less too sine the gears will last longer, that and the top end speed was increased quite a bit, or so it feels. good swap in my opinion.
edit:my tires are only 20's so that could make a diffrence in results