track tension and chattering

[sledneck_03]

my track chatters on the stand, what is the track tension on a 155 suppose to be??? i know the book says 3/8"-1/2" but what works best?? i tightened to track to 1/2"-5/8" and changed my sleds and the noise never went away. it even clicks when your driving over 5-10mph.......

like you would hear chattering in this video but you dont on this one and its a 144 of my sled.
http://www.youtube.com/watch?v=EGlPHP9WTB8

 

[defysgravity]

Follow the book....you need to ride it on the snow and listen to see if it's still ratcheting, then make your adjustments.
Could the noise be from your drivers contacting the clips as it spins the track?

 

[winter brew]

I don't think the noise is tension related..??? Is it the track clips chattering on the hyfax at the very rear of the rail??

 

[C S Fever]

Hey sledneck it probably isn't a big deal the most important thing is to not get it too tight, it robs major amounts of horsepower. Just make sure that things are even side to side and that it loose enough to let her run but still not rachet

 

[ElectroTech]

If you have front idlers still its the track running over them and slapping the sliders, this is also why the sliders wear where they do. Just try pulling the front idlers.

 

[AKSNOWRIDER]

polaris has a team tip for the tracks on a stand...they say they are supposed to be noisy..they also say dont run the series 5 tracks on a stand...I will see if I can find the team tip for you....here is what it says....
2008 700 and 800 RMK 155 / 163 Track Vibration on Stand / Track Tension Settings
The involute/convolute driveshafts installed in these snowmobiles are designed for a track that has been “brokenin”.
When the track is new and run (dry) on a stand, it may exhibit a tendency to climb the center drive, causing
vibration. If this happens, lubricate the track and driveshaft interface by spraying it with water. This will stop any
tendency for the track to climb the driveshaft.
There should be no noticeable vibration with the involute/convolute driveshaft, even when new, when it is run
on snow.
Additionally, it is very important that customers adhere to the specified track tension requirements as outlined in
the Owner’s Manual. Proper track tension is critical for maximum efficiency and performance. Track tension
controls the approach angle of the track to the rail beam in powder conditions.
Track Tension Specifications (Reference appropriate Service Manual for adjustment procedure.)
Deep snow performance will be optimized when setting the track to the specified tension. Looser track tension
settings will cause the track to “bunch-up” in front of the rail beam tips, causing an improper track approach
angle and poor performance.
The first sign of a loose track on a snowmobile using the new involute/convolute driveshaft will be different than
the traditional racheting under acceleration heard with standard driveshaft - track setups. The rider will now hear
the racheting noise during hard braking, whenever the track is too loose and in need of tightening.
Remember the track tension must be checked and adjusted after the “break-in” period and checked periodically
to ensure maximum performance.
SUSPENSION MEASUREMENT
IQ 121
136 Coupled
136 Comfort
7/8″ - 1-1/8″
(2.2 - 2.9cm)
M-10 128 7/8″ - 1-1/8″
(2.2 - 2.9cm)
M-10 136 3/4″ - 1.0″
(1.9 - 2.5cm)
IQ RMK / Switchback 3/8″ - 1/2″
(1 - 1.3cm)

 

[EricW]

If there is a section of the hyfax that is loose on the rail it can chatter pretty good too. If you get the weight off the track you can tap along the hyfax with a small hammer and punch and hear the loose spots. Makes a lot of noise.

As far as the loose track for more power thing, i think there is another consideration as well. Imagine the track leaving the drivers under power, the paddles are dug in (thats why they bend as they try to resist) and the part of the track closest to the drivers on the bottom side could actually be trying to push the rest of the track along the rails to mid way of the rear wheels. As that track is being pushed, the paddles are actaully trying to come together (reducing the C to C of the paddles) and causing the track to hump up between the paddles from the drive force. If this actually happens, then a loose track will be allowed to hump up (dont mean to keep saying hump) more than a tight track absorbing and distorting drive force rather than putting it to the ground.

On the top side of the skid a loose track will be allowed to rise higher in the tunnel (the track is oblong trying to become a circle) reducing the clearance between the paddles and the tunnel roof. This could close down the void needed for snow to pass through causing more parasitic drag and robbing more HP to perform the same function as a tight track that doesn't rise up and thus has more clearance.

Just something to ponder as you watch the boring commercials during the big game. EW

 

[sledneck_03]

If you have front idlers still its the track running over them and slapping the sliders, this is also why the sliders wear where they do. Just try pulling the front idlers.

yah i noticed the only place they wore was in the middle of the two outer wheels.........hmmm ill have to try it and move my scratchers almost to the front.

i also took a couple air tools and weighed them to 10lbs then i did what the polaris book says and tightened my track two full turns on the bolts to have it between 3/8th and a 1/2" that it specified.

the rear slides are cut at a 45 and are about a inch from the end so its not clicking on anything there....ill just try it out tomorrow.

also it clicks when driving as well as on the stand. ill take a video tomorrow and post it if its still making the noise.

And my rmk does not have a center drive but it has the two sitting inside the rails and they dont go threw the holes in the track.....

i checked it thoroughly and nothing is rubbing but there was two VERY large ice chunks on the top of the front arm that looked to be hitting the inside nubs.........i had to hammer them with a hammer to break them. if thats what it was ill be pissed. three weeks of trying to figure this out and its ice???