the general rule while learning any song, is, when you have some problem with timing, SLOW IT DOWN

if you can play it perfectly on time at bpm 40, and your fingers are fast enough, you`ll be able to play it at 100, 120 etc, etc...
some time ago my teacher asked about a song i think i can play very well. i said "under the bridge" he asked me to play it at bpm 40. i couldn`t do it. after a week of practice it came to me. and completely changed my perception of the song, groove in it etc. etc. timing is not all just chops and hands, it`s also in your head.