Chaincase lower sprocket bolt on 600 Edge

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Canuck_600

New member
Hey guys, i have a 2002 Polaris 600 Edge X, and yesterday and today were my first days out riding this year.
i put on around 260 miles, then as i'm going about 20 mph by houses, there's a "clang clang clang", and sure enough, the bolt that holds on the lower sproket in the chaincase broke. the head of the bolt snapped clean off, and now half the bolt is inside the driveshaft, and needs to be taken out
the bolt head and the bell washer also got taken for a ride around the case by the chain, so my chain tensioner was wrecked.
The worst part about all this tho, is that it happened to me last year, about 1500 miles ago. dealer replaced everything for free, saying edges had this problem, and sent me on my way
now it happened again, and i was wondering if anyone has any idea why that bolt would break? or any idea how to prevent this from happening again?
thanks a ton
 
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switch07

Member
I had a 01 edge 600 and never had that problem once in 12000 miles. My wife is still riding her 01 supersport with 7000 miles and no problems. I would make sure it is a grade 5 bolt, and use loctite thread lock on clean threads. Good luck.....
 
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daytripper

Member
I have a 06 600 classic. Same thing happen to me last year. The stock bolt is a 5/16 #8 grade bolt. I drilled it out and replaced it with a 3/8 #5 grade bolt. The #8 grade bolt is stiffer and has no give compared to a #5 grade bolt. By the way, a dealer told me to do this. This is what he does.
 
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t unit

New member
This is a common problem on these sleds. It is from the the torque on acceleration and from hard braking. The stock bolt isnt strong enough to handle it. Mine broke on my '99 about 6000mi ago, I upgraded the bolt to a grade 12 allen screw. Havent had a problem since.
 
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Canuck_600

New member
hmm, should i got for telling him to put in a grade 12 bolt? or the 3/8" Grade 8?

this is the stock bolt: SCR-5/16-18 3/4 HXHD/NYL,GR8-P
so 5/16" grade 8, and that doesn't hold obviously lol
i'll hopefully get a chance to talk to Ken's today and see what they say about it, and i'll tell them about the grade 12 and bigger grade 8

Daytripper: you haven't had any more problems since you put in the 3/8" grade 8?

thanks a ton guys
Happy New Year too!
 
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cih7250

New member
Drilled and tapped hole from 5/16-18 to 3/8-24 used longer 3/8 bolt (grade 8) and a little bit of blue threadlocker, all is well in chain case town.
 
srt20

srt20

Active member
I have had to do this, and my buddy did it last week. Use a grade 5 bolt. It is softer and has more give to it. A grade 8 bolt is harder and therefore more brittle. Grade 8 snaps easier. You can use a right angle drill and an easy out to get it out. You shouldnt have to remove the shaft at all, unless you screw up. The bolt snaps off from acceleration, which tightens the bolt.
 
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dopp

New member
the same thing happened to my wifes sled three days ago
busted the side out of the chaincase
$300.00 in parts
 
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makintrax73

New member
One partial solution to this problem that I have tried - place an additional small washer under the stock beveled washer. From the way this bolt is breaking so often the lower gear is side loaded which shock loads this bolt. The problem with the stock set up is if you torque the bolt to spec. the stock bevel washer is crushed completely flat. Now you have a situation where the the beveled washer cannot provide additional "spring" because it is already crushed flat. You also have all that stretch concentrated on the very small portion of the bolt between the last engaged thread and the head of the bolt.

The small washer between the bevel washer and the shaft was recommended on some boards as a way to: 1) Keep the bevel washer from crushing flat and 2) lengthen the amount of bolt between the last engaged thread and bolt head - just like a longer spring can stretch farther without breaking this increases the area over which the shock load is spread out.

Also - the hole in the bevel washer is much bigger that the bolt that goes through it. It cannot hurt to try and make an attempt to center the bolt in the hole when you torque it. If you think about the physics of a shock load with an off center washer it may cause a flex along with the stretch. If that occurs it is just like bending a paper clip back and forther - once that crack starts it is only a matter of time. I don't know if this helps but it defenitely cant hurt!

YMMV
 
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Canuck_600

New member
Yup Dopp, that happened to me twice last year
the bolt head blew a huge hole in the chaincase, wrecked the chain, broke the chain tensioner, and boy was i mad haha

so since it just happened to me for the third time, i'm fixing it permenantly
My driveshaft is being drilled and tapped for a 3/8" bolt as we speak, and that's supposed to be the best permanent fix
the new sleds have 3/8" bolts on the lower one, so polaris obviously realized it was a problem lol
you could also update the edge driveshaft to the new aluminum driveshaft if you wanted as well
the aluminum shaft doesn't flex as much, and it has the 3/8" bolt for the lower gear
 
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