Another primary clutch failure

[lakercr]

Out on the lake this weekend with a buddy of mine. First pull rolling on from about 30 mph, and this happened to him at about 100.

Things I know:

• STM weights
• Dalton B/G primary, Dalton B/O secondary
• 22/41, 8JP
• 1.25 Ice Ripper track
• Rollers had a bit of play in them and were going to be swapped out

It's been posted before, and I'll say it again -- these primary clutches NEED to be inspected frequently, and I would not be doing any hard pulls unless you know everything is 100% in your driveline.

I have no confidence in the stock primary, and won't be running it next season.

 

[1nc 2000]

Third picture really shows how worn out the roller bushings are.

 

[Shagnos]

I would not have even ridden it with the rollers that bad. I check my rollers daily and always carry 3 spares.

 

[lakercr]

Yup, that's the point I'm making here - these things need to be checked closely and often.

 

[hibshman25]

Thread title may be a little misleading, as the clutch castings were not the problem. Any clutch that has weights travel past rollers will likely sustain damage.

Are STM weights shorter than oem? As a conservative measure maybe mfgs could make weights a bit longer so when the rollers start to wear, there is no chance of the weight traveling past the roller.

 

[cannondale27]

Why couldn't a limiter be added to clutch to prevent this? Maybe check weights with just pin in and use a spacer to limit travel. Yes would leave some on table but safer and could gear to make it up.

 

[sideshowBob]

"Clutch Component" failure that result in catastrophic clutch failure.
IMO: These Winders have so much power that they need to be geared, depending on their flash, so they don't fully shift the stock clutches fully on a regular basis.
JM.02c

 

[TPAY243]

Was this a stock or tuned Winder? If it is stock and no tune you have every reason to be upset. But if your running a 300 horse tune on this thing with after market clutch parts it pretty much is what it is and the old saying comes into effect if you want to play you got to pay. These clutches were not designed for what they are being used for. Once you get a clutch to work the belt will be next then the drive train and so on down the line and then the tracks will be coming apart. You guys are making a lot of pony's with these things and something has to give.

 

[KnappAttack]

Any bushing wear in the rollers and they need replaced, but some people don't know how much a little is. Once they start getting even just a little bit of play on the axle, they need to come out. Even just letting off will allow the clutch to shift out and weights swing by the rollers when the bushing is wore out.

Expensive lesson for the fellow in this case.

Tune or no tune it makes no difference if the bushing wears thru. Once they star to wear, they will chunk out in no time at all.

 

[cannondale27]

Any bushing wear in the rollers and they need replaced, but some people don't know how much a little is. Once they start getting even just a little bit of play on the axle, they need to come out. Even just letting off will allow the clutch to shift out and weights swing by the rollers when the bushing is wore out.

Expensive lesson for the fellow in this case.

Tune or no tune it makes no difference if the bushing wears thru. Once they star to wear, they will chunk out in no time at all.

We all agree with that but its not reality for some. Either like you said its not realized how wore the rollers are or its a big ride and what was good at beginning of ride is shot by the end. Obviously this new Primary has at least one or more design flaws. This almost never happened with the old Primary. You were comparing Overdrive between the two earlier. Well here is how they got it. So like I asked. Why cant a limiter be installed in clutch?

 

[1049triple]

We know that roller bushing is the trouble. We just need to inspect them at least every 1000km. In my case I open the clutch almost 3 time a week, and sometimes 10 times a day, so for me this is not a problem. My rollers with duralon bushings are lasting more than 3000km. I dont think installing a limiter is the answer. People will only wear the roller more as they will think it is an insurance. Some people are even looking for more overdrive... Again, the simplest way is to inspect your clutch often. We run top horsepower machine. We should take the time to inspect things carefully at that power level. People that only want to put gas and pin the throttle, sorry but this isn't the sled for them. That's the reality.

 

[Crossfire12]

Big HP 270-300 hp ,etc,should have Pro 4 or TAPP , you pay for HP if you want that much, stay stock, run stock components, safer.

 

[hibshman25]

We all agree with that but its not reality for some. Either like you said its not realized how wore the rollers are or its a big ride and what was good at beginning of ride is shot by the end. Obviously this new Primary has at least one or more design flaws. This almost never happened with the old Primary. You were comparing Overdrive between the two earlier. Well here is how they got it. So like I asked. Why cant a limiter be installed in clutch?

I am not a clutching guru but i like the idea of a mechanical stop to physically limit travel of sliding sheave to a point that weight can’t pass a severely worn roller. Maybe a bushing/collar on spider shaft for cover to bottom out on?

 

[KnappAttack]

We all agree with that but its not reality for some. Either like you said its not realized how wore the rollers are or its a big ride and what was good at beginning of ride is shot by the end. Obviously this new Primary has at least one or more design flaws. This almost never happened with the old Primary. You were comparing Overdrive between the two earlier. Well here is how they got it. So like I asked. Why cant a limiter be installed in clutch?

The limiter is the two sheaves hitting together and it works as designed. The problems arise as the bushing goes south and the wee bit shorter weights run past them, or the bolt on the roller breaks and/or the nut vibrates off and the bolt falls out of the roller allowing the roller and axle to dislodge from the spider.

 

[stevewithOCD]

My STOCK rollers with my STOCK set up wore out quicker then when i tuned it.
Of course i went through 5 sets total. I changed them so much the nuts wore out.
So now i have a whole bag of new nuts & a gallon of Loctite.

I have more Loctite on my clutches then belt dust now...