Arduino and robotis dynamixel servo

Forum 2005-2010 (read only) Hardware Interfacing
3

Serial.print(0x03,BYTE); // 4.Length of string
Serial.print(0x03,BYTE); // 5.Ping read write or syncwrite 0x01,2,3,83

(RX-64 user guide)
LENGTH 
 It is the length of the packet. The length is calculated as “the number of Parameters (N) 
+ 2”.

You're wrong on the string length. The write command use 2 parameters so you should send 4 as the length (number of parameters + 2)

You never release the bus at the end of the function so there is a bus contention when the status packet is sent by the servo.