WTF ? This is the second time we have twisted off a clutch shaft in the same way. WTF ?
This happened right after the speed runs at the airport on my brothers machine.
I just noticed it today. I noticed it because I always paint the bolt,wahser,clutch face so that I know if the bolt comes loose.
Does this happen to any of you guys ??
CO

Contact Comet

Imbalance issue? Weigh pucks..

Since it has happened twice on two diff machines I would think the issue is in the clutch. Fatigue, to many rpm for the clutch, to much power beyond it's rating, out of balance.

Just guessing, weld it up CO style and run it.
Is that a 94c duster? No doubt you will get to the bottom of it.
Can a new part be bought or do you have to replace the whole thing. Not familiar with them.

Time to slap that c102 on there

I have a 102c but it's on the death machine.



Yeah it has happened on two different machines now.
I don't know if it's a balance issue like hoser said but I doubt it. This was a new right out of the box 94c when I put it on. It's not some gibbled together brain fart test rig I was experimenting with.
Notice also that the "D" is all hammered out.
On the other one that twisted off I made a new stem on the lathe. There is a thread about it and I think that's the one I have on my machine with the homemade clutch pucks. It works well.
We have a brand new 94c sitting on the shelf that I'm gona install ------ WTF ??
CO

I had a Skidoo TRA clutch come apart on me, after that that the crank had some run out, twisted, it's kind of chicken or egg situation, did the run out on the crank cause the clutch to fail or did the clutch failure cause the run out, Either way, be sure to put a dial indicator on the crank snout before putting anything back on.

Good idea, I will do that and post.
First I have to find the tooling I used the last time to take one off. It was a challenge.
CO

Well that sucks
The way it was all chewed up I would have never guessed it was new. With it broke there are you going to be able to get it off. The D damage may have been done after it shears.
If under warranty I would send picks before you do something to get it off so they do say you did it. Ask them how your supposed to remove to ship back.
You would think if one was going fly apart it would have my back yard hackery at 8450 on two wore out ones frankensteined toghter.

Look forward to what you find

Sorry I may not have explained it correctly.
When I say new clutch, I mean it was brand new when it was installed. It has several rides. No chance warranty is still on it.
As for removing the back shiv, this won't be an issue as I have done it before. Just have to find all my tooling. There is a thread on the last one I did but the Engine was out and laying in the Engine stand. Might be more of a challenge with it still in the machine.
CO

Removing seems like a major pain, it almost seems like you would need to weld a nut on the end so it has something to push against.
or at second look maybe you would have to tap threads into what is left or is that the crank right there.

I just checked my notes. The other clutch that blew this same way was also on my brothers machine at the time. Hummmmmm.
Anyways I found the thread and this is how I will be taking it off: viewtopic.php?f=1&t=19501
I know what you are suggesting above but I'm trying to save this clutch and use it as a spare.
CO

Just publishing some vids to youtube.
Will post them here when done -- 30 min ??
CO

Edit:
Held the camera the wrong way damn: https://www.youtube.com/watch?v=Kjj6lH8a9ZQ
Take two: https://www.youtube.com/watch?v=loDhp2ymjv4
CO

Take 3: https://www.youtube.com/watch?v=HtYqRm_vIZU
Take 4: https://www.youtube.com/watch?v=igRELyAeyP4
CO

Wow!
I'll subscribe to the CO channel.
I gotta ask, what torque setting you using on that clutch bolt. A very very small dab of anti sieze would help ya there. You smacking that bolt pretty darn hard or so it seams. Kinda hard on crank shaft. I like the avgas comment, spit my coffee out this morning.
You should do more video. Most would find it helpful is so many ways.
Hope you find out why it was shearing off. One item to check would be weight position on run out. Post up some pics of the belt.
Like I mentioned I no noting about that clutch so more info for me the better. Maybe do a video on how it works. Some info on weights etc. Turn this into a teaching moment.
Thanks, Andoh

Forgot, since that is a new clutch with a set of paper work. Can you snap pics so it can be logged on this site for others. We can post a link to this on CSI central.

Not sure what you are asking in this comment.
Are you asking for the paper work on the clutch that busted or the paper work for the new one I'm about to install ??
CO

1) I'm using 60 ft/lbs torque on the bolt and actually use blue loctite NOT anti seize. None of my bolts come loose so if the felt marker lines don't line up then I know something is really wrong. Also that bolt I'm smacking is just the pusher bolt and it's pressing on a temp bolt that I've got screwed into the crank. The puller is pulling and the bolt is pushing. Shouldn't be any load on the crank.
2) Yeah I've got to look at this clutch shearing problem. First I've got to do what Kuma said and run a dial.
3) I'll post pics of the belt later today. Will also re-load that first vid that was sideways. It plays fine on my computer so not sure what happened on the upload.
4) You spelled your screen name wrong. Darn dyslexia.
CO

Hey, it was early this morning.
Anti sieze on the crank. Makes it easier to pop.
Instruction on the new in box unit.
Looked to me the old and new are the same unit.

The bolt torque may be different than stock 60 if that is what it is. I'll look at manual and see. Blue on that bolt I think is a good idea.

Sometimes the install info has cool data.
Adnoh, honda. Yep got it right.

Still want more you tube.

Ok found what I was looking for.
The bolt torque is 45-55. So 60 probably not a big deal.
Your brothers machine has a race Engine.
Max HP on 94c is 40 hp.

It does look like that shaft is a replaceable unit. I like the idea it can be shimmed at that point for different belt sizes.

The back set uses different part numbers.
So on and so on.

It does mention smacking it with a hammer for cover removal only. We all know removing them a lot of times it needs a smack.
I would recommend a very very little anti sieze only on crank and reduce to 50 on torque and still use blue on bolt. Then try to remove with puller and see how it works. If you don't like than clean and run in at 60.
One last thing clean up the crank in prep for new unit and test fit before installing bolt. Then put in bolt and torque to 30 and check run out, fixed plate running true. Then move forward with set up.

Pretty cool stuff once you start reading.

1) I wonder if that's the issue with this problem. A stock oddy Engine according to the dyno runs is about 33 HP. Now juice up the Engine a bit with some work. That 40 HP Max for a 94c might be a bit weak now.

2) Anti seize: As a millwright we were trained to NEVER put anti seize on a taperlock. There is a good reason for that. Taperlocks in sprockets and shivs use friction for holding power. If you never seize the crank your clutch can slip. You never seize straight bores.
I may be wrong but that's how I was trained back in the 70's.
CO

I just tried to reload that first video but it turned out the same.
Oh well I guess you have to turn on your head to view it if someone really wants to see it.

It's raining here now and probably will be for a week now. That's normal around here. I really wanted to go up to silver tip mine because I heard the road was open now. Oh well. I haven't been up there since the late 1970's. Damn.
CO

You would know that better than me about the anti sieze. No training here.

I got some pics to upload from what I found good info for site.

Hope you don't mind.

Few more
Getting my pop corn and cold ones ready for your up load.

Here are some pics of the belt you requested.
CO

Is the stem the part you need, # 3 in the diagram? Looks like it can be purchased. https://www.mfgsupply.com/205580a.html