[Jim]

Be sure the gears are lubricated with a sticky grease.

Turn the drivetrain by hand; sequentially removing items from the system. You may find one think mis-aligned that is causing the lion's share of binding

ALWAYS ALWAYS ALWAYS use a fresh, fully charged battery. V=IR, low volts and these new motors become "amp hounds".

When you hit the pits at your first regional, be prepared with a game plan to quickly and methodically approach this problem.

Good Luck