I just gotta say, HOLY CRAP! .... I removed the stinger from my exhaust and richened her up just a tad..... WOW! Add a little bottom end? The different is night and day! (I think I might have lost a TINY top end speed though).
I'm just completely stoked at the difference, its a new buggy all over again!
make sure that you have 2 spare clutch screws, i got 5 mins run straight outta the box an BREAK goes the clutch screw, my mate got about 30 sec to a minute untill his broke. all that way to find a track an it took longer to pack up an unpack then we got to bash.
This happened to me yesterday. I checked the diff like everyone said and it was good but maybe 5 minutes into the very first tank the cap screw holding the pinion to the clutch bell snapped in half. Very frustrating but she's all back together now and I finished running that first tank today! I may never run any other RC again!