Strange knocks from driveshaft on left hand side

[srx700lt]

I'm working on a Sidewinder S-TX -22, when bringing it out from storage it hade a noticeable knock from the driveshaft. It sounded like and felt like it was on the left hand side. So I installed a new bearing and expected it to solve the problem. But I still have some knocks and noise and today I removed the secondary clutch to be able to se and feel the tunnel better. Still a noticeable knock that I can feel when I put my hand on the side of the tunnel by the break disc when i spin the track by hand.
I also opened up the chain case today and it looks to be in good order. The sled has only made about 1000km.
Anyone have any suggestion what is the issue?
Is it possible that the new bearing isn't seated properly?
Or has anyone had any similar issues?

 

[KnappAttack]

I'm betting either track noise, disc and/or brake noise. They do make a heck of clatter when on the stand. The track hits the top arm, the drive sprockets hitting the track do as well, and the brake disc on the splines and the pads in the caliper.

Take it out and ride it and see how it does and quit listening to it on the stand. They sound horrible when on the stand and I noticed it worse on the newer sleds with the tall spindles with the different suspension settings on the front arm. I thought I had a chain case problem on my 23 and it was the studs hitting the front arm guides making a heck of a racket.

 

[Norse]

Check all wheels for alignment and damage, maybe check for even wear on the hyfax. It is noisy on a stand, but should be much more quiet out in the field.

 

[srx700lt]

Ok, I did some wrenching yesterday and I found out that if I loosen the track the tooth on the drive sprockets misses the hole in the track, it hits the track between the openings when I rotate the track by hand. It looks like the pitch differs between the drive sprockets and the track. I can see that the tooths position in the hole in the track moves if I rotate the track forward and backwards. The drive sprockets is marked Arctic Cat 2602-912 and they seam to be 2,86 pitch. The track I forgot to check but will do that in the end of the week when I'm going back to my cabin. Meanwhile, does anybody know where I can find a cross-reference between Arctic Cat and Yamaha part number?

 

[KnappAttack]

The drive sprockets always have lead to them by about 10 thousands per tooth. This is done to keep each tooth engaging the next lug coming onto the sprocket when under power. When just turning by hand, the track is always trying to outrun the drive sprockets and climb over the sprockets. If you have the track loose it will try to climb up over the lugs after a few revolutions on a dry track. This is why we run the track tight and with lubrication and in snow.

If you have not changed the pitch on the track or the drive sprockets everything is OK. The only way you would have a major mismatches if you or someone else changed the pitch of the track or drive sprockets. Tighten the track and go ride it.

 

[sideshowBob]

I agree with Knapp as well.
But....If you are not the original owner of the sled then it is possible someone may have swapped tracks from a 146" 2.86" pitch driver track to a 144" which is a 2.52" pitch track? Unlikely but anything is possible. a quick measurement of the distance between the track windows should tell you which track you have then you could also measure the distance between the tips on the track drivers themselves, compare the two and they should be very close to the same distance.

 

[srx700lt]

Ok, I have measured the track and the drives and to no surprise they are correct. But the track was very tight when we got it back from service last time and the sled was barley used last winter so I didn't think about it much. But once I replaced the bearing on the left side and reset the track tension to the numbers in the manual, it all works well. I may hear some noises when letting of the throttle and rolling to a stop but it is just minor noise now. And as a bonus point the skid suspension works much better with the correct tension on the track.
So thanks for your feedback guys, my girlfriend is now comfortably riding the sled.