yes the naro hp is VERY tight.
basicly just pull it really hard.if not pluck it off with some plyers vey gently.
if you are 360deg modding it its and idea to dril the hole out on the gear to make it a little more free...

i was the same when i got my first naros... you just need to pull hard :P

as for 360modding

try looking through these 2 sites and see if you find something, if not ask on their forums im sure you will get a good answer

http://www.robotwars101.org

http://antweight.hostrobot.co.uk/