Every now and then you get a clutch that is REAL stuck.
99% of the time you can get them off without resorting to a few solid blows to the end of the clutch puller with a hammer, but then there are the times common sense lapses and out comes the hammer. Here is proof that the hammer should stay in the tool box.

[attachmentid=31027]
My zr600 rolled over 10,000 miles so I tore the lower end down to replace the bearings, you can see the cracked race on the right (pto) center bearing.
Not sure if it did any real harm, but it did allow for crank end play.

Oh, and I remember this incident. It was at about 6,500 miles and I had tried heat, impact gun, grease and nothing budged it. I had a ride that I wanted to make that weekend and I figured it was my last resort before cutting it off. This was 3 or 4 good thumps with a dead blow hammer.

My guess is your impact gun did more damage than a dead blow. I use a dead blow hammer every single time I take mine off.

I can almost 100% guarantee you that the damage is from the dead blow.
The broken part of the bearing is right at the half clip that holds the race from any lateral movement (acts as the thrust bearing). Now that I have the crank apart I can see that the crack is almost all the way around the bearing recess for the clip. This damage could only be caused from excessive force from pto side to mag side (like smacking the puller with a hammer). Also worth noting is that the locator pin had damage that was from front to rear, not side to side.

Not that an impact could not cause damage, but it would be more of a rotational twist of the bearing or race, I suppose it could cause a lot of stress on the locator pins for the bearing races or even possibly put the crank out of phase if it could hammer hard enough, but it would not cause the damage that I have.

I even had the head of the engineering dept here looking at it the other day (They love looking at any mechanical failures so they can over analyze it) and they agreed that it came from an excessive force from behind the bearing.
Their advise, don't hit it with a hammer (all that education and thats the best they could say).

I use a dead blow hammer every single time I take mine off.
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I'm gonna have to agree i think there was only one time i was able to get mine off without a hammer, but i try to take it easy with the hammer. But it can't be that serious if you put 3500 miles on it and nothing happened either that or you were really lucky.

Now that I have it apart I feel that I am very lucky. The race finally started to crack through from other parts of this main crack and the rollers were just starting to get marred from the uneven surfaces. It probably did not have another couple hundred miles left before the rollers would have been chewed up enough to get spit out.

I imagine that the crack started back during the hammer incident (I didn't hit it for all I was worth, but I did really lay into it few times) and has slowly gotten bigger over the past couple thousand miles. It only had another 1/2 inch to go before the crack extended all the way around the race.

I service the clutches often on my machines (at least once a season) and most of the time they come right off if I follow this procedure:
-- Fill the clutch bolt cavity with 5 or 6 pumps from the grease gun.
-- Use a good quality ball bearing tipped puller.
-- Use a breaker bar with a pipe on the end of it.
-- Find a way to lock the clutch (I built a bar that will go through the clutch towers and rests on the rear belly pan support).
-- Give it he!!
I typically have 9 out of ten just pop off.

Back when I was a little younger I worked for a Polaris / Ski -doo dealer as an assembler. One of the techs was fond of running a length of rope into the spark plug hole to essentially 'rope lock' the cylinder and hold the crank stationary and then use a breaker bar to tighten the clutch puller.
To this day I can not see how that is a good idea, but that is how Polaris trainig showed him how to do it.

Thanks for the tips, hopefully ill have the same luck you have had with that procedure. With a bar through the clutches though, not too sure about that rope lock thing. You sure must have been happy you tore it down when you did, just imagine all those pieces of metal flying through the motor. OUCH.

OUCH is right! Geez, who'da thunk 8,000 RPM could be so unkind.

Have to admit the majority of times a shot from the hammer pops our clutches off. Watched a friend use this method many times and he is an ex AC dealer. :crazy:

ya know...i pop my clutches on and off often, when i used to grass drag i`d average 7 to 10 times a week between two sleds, now at least 2 or three times a season just to mess with stuff. anyways, i torque em to 65 ft pounds, i used my holder and a breaker bar and they come off with minimal effort. i think a lower torque puttin em on helps alot....and no , i never had one come loose.

OUCH is right! Geez, who'da thunk 8,000 RPM could be so unkind.
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Yup, I'm afraid thats what it would have looked like.
That looks expensive :(

To mess up the locating pins, You'd have to really smack it. Not to mention I would think something else would be loose too. You might want to look for something else being wrong too. It just doesn't seem right. You guys use a Rubber dead blow correct. Or hard plastic?
That's what I use anyway. I have on occassion put on a metal regular hammer, but just light taps to try and knock it off. I've never had to hit them full swing. Good luck

I have never used a deadblow , I always use a small ballpeen hammer