Primary Clutch TRA 7 800R Blew Apart

So here is the scope.....riding up in the Snowies about 9,000ft. The sled is a 2008 Summit 154 Summit 800r with HPS Can, DJ Clutch Kit. The rider mentioned mid that he felt vibration in the handlebars, later mentioning the vibration had gotten worse and there he wasn't hitting full RPM. He could barely get it above 7,100RPM, so he asked me to take it for a spin for the last leg home. Sure as poop the sled felt almost fine at idle, but the more it crept up in RPM the more vibration I felt... so much where at around 6,500RPM it almost hurt your arms to hold on.

Well the next morning we looked over the sled checked the usual suspects of ice, belt, driveshaft etc.... only to come to the conclusion that the rider had the spark plug wires on the wrong side. So we swapped the spark plug wires and the sled felt like less vibration and was hitting full R's (apparently Mavrick Motorsports informed us that the wires can be on either side)

Anyways we unload after a morning of wrenching on a few sleds to hit the hills... about 1/2 mile trail up the sled locked up shut down and came to a immediate stop... first thinking the engine seized up we slowly pulled the starter only to fell it not move but the sled inch forward, but didn't think about that. So while figuring out how to limp the sled home we noticed the belt locked half way into the primary and further inspection showed a primary roller arm had broke and locked the primary open. Knowing this was our last day we pulled the sled back to the trailer and the rider went back to the cabin to enjoy a day of R&R.

So the last two night's I have been pulling the primary apart inspecting and cleaning everything. So here is my question... What happened? I have some pictures coming in a minute. I first thought a roller went out, then maybe a cotter pin inched out, but now it appears that the out sheave primary bushing went to crap (not the spring cup one)... the ones that DJ, Winter Brew, and others have been preaching to us to change on the 07's and 08's to update with real 09 stuff. To me from looking at that bushing and comparing it with other ones it has almost wore down to the point where it doesn't even seem to be there, if you look at it has almost wore down to the primary's bare aluminum. From there I think all that slop cause a whole chain of other things to stress. I think it caused maybe the roller bushing to loosen up to then causing everything to get out of wack making the arm catch, lock and crack.

What do you guys think... am I off... did something else happen I am not aware of? Please HELP...

Also what do we need to replace, do we have to replace the whole clutch? ... it looks the inner sheave is fine as well a the out cushion/ramp half. You will see from the pictures the snap ring in the outer sheave bearing came out bent the aluminum and the aluminum is all messed up. If I am only replacing parts does the clutch need to be balanced now? Please help!

I have also noticed there has been excessive isoflex grease spay out of the crank seal compared to the other XP Summit 800R's in the group. I haven't put a dial indicator up to the crank ( I don't have one or bore gauge to check the bushing spec's) , but would poor run out on the crank cause the primary to grenade?

What are your thoughts.

Lots of pics to come!

Thanks
Shawn

Look at the wear on the inside of the primary bushing!

These appear to be the good pieces

If you look at this pic you will see the big divot in the inner side where the arm locked into the clutch. Is that ok? Just rebalance?

teeroy said:

Joey, are some '08 clutches better than others in the materials used? I have just torn mine down for inspection after 1700 miles and there is no visible wear, rollers and bushings are all in good shape, I am even running the original spring cup that came in the primary. the second one we tore down only had a bad roller, other than that it was in great shape too with just over 1000 miles on it. but one other machine in our group has had bushings wear quickly, it is on it's 3rd spring cup and recently had the bushing changed again on the sliding half and he is at 1400 miles. all three machines are using your kit....any ideas why two have been good, and one keeps wearing out? mine was a late '08 build, the other two are early production models with serial numbers one apart.

Click to expand...

It's got to be Joey's clutch kits j/k j/k j/k joking LOL.... I am sure he has gotten that one before... Hey Mr. DJ your clutch kit caused me to break an arm from all that weight you told me to ad to ride my Mountain sled in Iowa. You owe me a new snowmobile.

Anyways without a measurement does the sliding half bushing look fine? or am I freaking out? I might grab one of those arms from you Joey, unless I find a local dealer that has one in stock like yesterday.

Thanks
Shawn

I had one of my dalton cotter pins on my sled break at the ends during last inspection... put the old ski-doo one back on.

I would like to think it was one but we had the primary apart 3 days before that inspected the pins, made sure they weren't moving laterally and tightened them up just a hair for security. Also I would think if one of those let go I would have seen a little more odd wear on the ramp and the roller specially.