this graph can help.... maybe..
im glad you said big shaft on the GRRT, i've been trying to find out what size it is., got M6 for 40's, then i found a nut last night that didnt wanna fit, did it up, past the dirty bit of thread and now its fine, think the nut says 8, so M8..
the old 8x8's we had shed blades, the new ones are thicker and dont. didnt know they had been changed till i found out here, yay RCU
