The original 9mm pultruded carbon fiber tubes were cheap tubes with no tortional strenght one crash and they cracked length wise. (unidirectional fibers)
The 10mm tubes are role wrapped and have much more torsional strength.
New motor ends needed to be 3d printed from PLA, luckly drilling out the central hub arm holes from 9 to 10mm went well using a bench press.
The motors, distance between the holes is just under 10mm which means the tubes and the 3mm bolts have a bit of an interference fit.
Printed bungs on the ends of the tubes to help support the compression force when the motor ends are placed. 4mm Aluminum pegs fix the arms into the central hub.
4x 3mm bolts (22mm long) compress the two parts onto the end of the arms and fix the motor.