Some come off easily, some do not... the 900's were spec'd out at 96 ft. lbs., and also came off with difficulty.
I no longer use the typical puller to remove the clutches and now use the hydraulic method.
I have, and use, the Perks "no wrench" clutch puller with water...some people are successful with a bolt. Hand force on the tool is all that I've needed on my machines. (I prefer Cascade Clutch Performance or Indy for Balancing and will only use them)
I also only fill the cavity by tipping sled on its side so no air is in the cavity.
http://perksbalance.com/products.html
This hydraulic method is more friendly to the crank and clutch as hydraulic pressure pushes on the entire pto snout... rather than just inside the bore of the bolt hole.
But... if the clutch hub is cracked or otherwise compromised prior to pulling... you can still break the clutch... but, IMO, better now than on the hill.
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