I used a 17 tooth bearing mounted idler sprocket for the chain tension device which was bolted to the inner slider tube. Note that the motor is mounted ahead of the axle and the jack shaft is behind the motor. Try to get as much weight as possible ahead of the axle rather than behind the axle because with a solid axle and dual wheel drive without a differential, the buggy has a tendency to want to go skid forward on a hard surface when making a sharp turn. The more weight you can keep forward the better it is to improve steering bite. With a differential like on a car, steering is easy because the rear wheels can turn at a different rate since the turn radius is less on the inner wheel than the other wheel.