What caused this damage to my 3" track: X3 with Avid Drivers.

[cascadesnowjunky]

No drive shaft stub end failure. I helped take it apart and we checked that. I was really confused at how it could only damage one row. My first thought was something was caught in the driver but no signs of any damage to the driver. I also thought maybe the rear wheel had lost a bearing and moved over and was rolling across that row of nubs but the rear wheels and bearings are good. Very confused. I want to go back over and look closer at the driver alignment, if srx is correct and the drivers are installed on the wrong sides that could definitely cause them to be out of time. Very strange to say the least.

 

[YOOPERREV]

I'm thinking that the rails/skid may be bent and the damage is coming from the rear wheels.

 

[mountainhorse]

I think that Tincat's second picture shows the problem. Something is causing the track to want to go to the left really bad. That one row is severely pushed over to the right. I don't know what the track tension side to side is. I'd check it. The spacing on the drivers looks about right. Maybe the left hand driver could be moved to the left a little. That way the left hand track force would be shared by two rows of drive lugs in stead of one. That would be just masking the problem.

Robbie,

The driver directly over the problem involute-drive-nub is noticeably more
'proud' than the other driver... circled in this pic below.

Could this be the cause of the problem?

Something is riding up on the back-side (braking-side) of the internal-drive-lug and "squishing" the drive lug...
the oddity here is that it is only one line of drive-lugs... and all the
others in that row are unaffected.

If the track were moving to the left really bad... I would expect the compliment line of lugs on the mag-side outer... to also be 'squished'....but it is not. Also... for the driver to move to the right... the Mag side driver would also need to move to the right and again you would see the issue on the outer line of lugs.

Curious.

TNTCAT

Yooper may be on to something... hang the rear of the sled and look for any bending, check the suspension for any broken cross shafts or bent brackets... or maybe a rear wheel that has the bearing clip missing that is allowing it to move on the shaft.

What does the Upper idler look like? Is that securely positioned? Is the bearing for upper idler tight and rolling free?

What about the rub-loops on the top of the front swing arm... are those intact or constantly rubbing?
Out of curiosity... what is your track tensioning method... and how often do you do this?

Is the track centered in the tunnel with the center tooth in the middle of the drive window?
(ie, is there equal space from the edge of the track to the inside of the tunnel on both sides...
with the center drive centered in the window)

.

 

[cascadesnowjunky]

Mountainhorse I was there to disassemble with him and we looked at all the obvious like track running hard of to one side, c clips holding bearings on idlers, and loops up top skid. The bearings on the drive shaft are good as well as bearings in the rear wheels. We looked at the edge of the track to see if it had come way out of alignment and started to fray or melt on the edge frome rubbing on the inside of the tunnel and didn't see anything obvious. We appreciate all the ideas on things to check as we are both baffled. I am going over tonight to get hard measurements on driver spacing etc. It has to be something that happened fairly quickly, I have ridden this sled a fair amount and not noticed and abnormal vibration. Are there any more pictures or any specific things you can think to have us look at tonight?

 

[mountainhorse]

carefully re-inspect the upper idlers... easy to pull skid... and you can then clean/grease it as a side benefit.. allows you to check all of the skid components on the bench.

Also... gives you the ability to check to see if the drivers can be moved around on the shaft with no tension load on the track.


.

 

[roni87]

Checked the little wheels on the front track shock?

 

[rmkboxer]

why is it using the center holes, I have never seen after market drivers use the center hole, that looks like a dumb idea. why not do it right and use the clipped holes.

 

[mountainhorse]

Center drive is an option for those that would prefer not to trim the rails for tooth clearance.


.

 

[diamonddave]

Center drive is an option for those that would prefer not to trim the rails for tooth clearance.


.

And is what Jack Struthers at Carl's Cycle prefers....

 

[cascadesnowjunky]

Well, went back over there last night to check a few more things. The drivers are perfectly centered and the spacing between the two is spot on. Things that were checked are drive shaft bearings, idler wheel bearings, cross shafts, no bent rails, no bent tunnel, no rubbing inside tunnel or bulkhead, all c clips and spacers in rails and wheels are in place, no other abnormal wear like it was tracking way off, track clips are all good. It was mentioned by Carl's that it may have been a broken shock bolt that walked out into it, but all that was fine. It could not have been that or it would have tore them up not flattened them. With that comment I believe it was not a stationery object or like I said they would have been shredded. I am curious what Carl's says when he takes it down friday, I hope they have some idea. Definitely sucks to spend almost 2000 dollars and have this happen 300 miles later. Plus anyone that knows Tony knows he takes care of his stuff, he is very meticulous. Here are a couple pics of the measurements to check the centering of the drivers in the tunnel.

 

[black z]

Possible that the driver is slipping? Did you check track tension?

 

[rmkboxer]

And is what Jack Struthers at Carl's Cycle prefers....

interesting, so run a driver that you have to run a really tight track or run extroverts that actually work.

 

[LoudHandle]

interesting, so run a driver that you have to run a really tight track or run extroverts that actually work.

A tight track transfers HP and delivers more performance under power. The only advantage to a loose track is pushing the sled around in the garage. FWIW


The "A loose track delivers more performance" is an urban legend propagated by those that sell extroverts and anti stab kits (read:AVID).