What size is the bolt inside the drive chain sprocket?

[stuckonreplay]

What size is the bolt inside the drive chain sprocket? The one that is where the roller chain spins on. I know the tool came with the kit but mine didn't so can someone tell me what size it is? Thanks.

 

[JonnyR]

i think its 3/4 inch

 

[bairdco]

19mm socket.

 

[MotorBicycleRacing]

i think its 3/4 inch

3/4" socket will fit a 19 mm nut as it's almost the same size.
You do need a thin wall socket to fit that nut.

The tool that comes with the kit isn't worth using unless you
are desperate.