'84 250R bore size? Urgent!!

Hey guys, could someone look at a manual and tell me what the stock bore size for an '84 ATC250R is? I have an '81 CR250R that I'm working on for a buddy and his cylinder is wore out and I want to see if a spare '84 cylinder is the same. The '81 is 69mm.
Thanks in advance for the help.

Regards,
Josh WInter

[kimmer250r]

The bore size for a 81 is 70mm and the bore for a 84 R is 70mm. The cylinders should be interchangable.