I had my 2005 c/c ds reworked with new batteries and 400amp controll + 4.0 cables by the now defunct K&H Freedom carts...best they could do was 22 mph...sent the motor to plumquick in NC and they had it back rwound in 3days..installed ion 20 minutes and now get 25+mph with good torque for $225 plus shipping. They know what they are doing...check their web site and then give them a call.
