We've attached gears manny ways in 7 yrs of competition, and the best way so far is by on e of 2 methods, 1) using a hex broach to put a "X" diameter hex in the gear and using a piece of hex stock on the shaft. Keep gear in place with a snap ring. 2) If no broach is a vailable then bore a hole in the gear and weld a "Craftsman" 7/16, 1/2" socket in place and use a apiece of hex on the shaft. Works extremely well and the gear is easily removed and serviced. Also used this "hex coupling" on the output of the trans unit to make it easy to separate the trans from the drivetrain for fast servicing. We could remove the trans in under a minute last season.
