Freeze the transmission shaft or heat the clutch basket. Sometimes a combination of both.I prefer CRC freeze-off. My 66's is a bitch to get off.

 

 

The reason it comes apart hard..is because the Taper was a More Precise fit... Critical for Operation... sloppy tapers cause many Problems... Do Not for a Moment believe that the tiny little key can Drive anything... if it could, that would be a Straight Shaft...

 

like PREZ said-- its the taper that holds the hub to the shaft not the key -- theres like 1 degree difference between the shaft taper and the hub taper-- this is what holds it -- also theres no reason whatsoever to tighten the hub nut down like its a nut off a GP3500 train -- a dab of blue loctite and a couple of burps with an impact is enough -- myself on my stuff i have never had a hub not come off - i tighten the center bolt on the puller and give it a wack and it pops right off-- never on the shell --

when we raced briggs alcohol karts the flywheel has a taper and a key - the 5 hp has no advance/retard so you use an off set key-- when you get into limited mod and open motors you use a degree wheel to set your timing when you find the amount of advance you want ( methanol uses about 5 to 7 more times of degree of timing than a stocker ) -- you lock the flywheel down and your good to go-- these engine turn 10,000 rpm and i have never had one slip timing --