durga build question

[foxhound1]

i just finished building my tamiya durga db01, i have a castle creations sidewinder with a 5700kv motor and a spectrum radio. I got it all programed, but when i hit the throttle it sputters as if the belts were slipping or as if something was not connected correctly. I went back and tightned the diffs to see if that would help, but nothing changed. If someone could please help me i would appreciate it. thankyou