Some interesting thoughts on QD failures....

[Devilmanak]

After parting both 2013 and 2014 Pros, I am noticing a LOT of part number changes between the two years that Polaris has not acknowledged. (I read the post below about Polaris' solution to drive issues and they did not mention a few things.) To their credit, that seems to be their policy, on and off the race track. That is marketing, I am sure all manufacturers are like that. They do NOT like to acknowledge fault or product failure.
Everyone by now knows that the 2014 has a new quick drive belt, and new machined upper and lower sprockets. The backer plate is the same. The general consensus on failures (from Polaris) is lack of break in, which I am starting to seriously doubt. Yes, the 2013 sprockets were cast and a little rough, and would smooth out with some break in, and yes, (maybe?) the belt needs heat cycling to toughen up.
What people have ACTUALLY found is that when the belt rides against the upper sprocket lip, it gets hot and fails. (Do to misalignment, bolts coming loose, bearings going bad, etc.)
What started this thread, is that when I pulled the 2014 jackshaft, I was shocked at how LARGE a diameter it is, I do not remember the 2013 being so huge. I just checked the part number, it has changed. This is telling me that the 2013 shaft was too small for the load and was flexing, so they made it larger. If the shaft flexes, the upper sprocket will angle down under load, and make the belt walk into the flange, causing heat and failure.
Another thing I noticed is that Polaris parts costs have skyrocketed for 2014. A large percentage, the qd belt retails for $200 this year. The pullies/sprockets are expensive, and the lower is not available from Polaris when I checked last week. Are they bumping costs to try to cover losses?
Thoughts?
Chris

 

[rmscustom]

The QD belt was $200 last year. My dealer just traded me a 14 belt straight up for a new 13 belt I had from last year.

 

[Devilmanak]

Guess it depends where you buy it, Babbits lists them at $163, straight from dealer was $200. I know I sold takeoffs last year for $80-90, I just sold the 2014 for $160.

 

[Devilmanak]

The QD belt was $200 last year. My dealer just traded me a 14 belt straight up for a new 13 belt I had from last year.

And THAT is a good dealer!

 

[rmscustom]

Guess it depends where you buy it, Babbits lists them at $163, straight from dealer was $200. I know I sold takeoffs last year for $80-90, I just sold the 2014 for $160.

Not saying I paid $200 for the 13 belt but that was the list on it, same as the 14 belt.
And yes my dealer is awesome

 

[mountainhorse]

Devilmanak... Thank you for the great thread and for your insights.. not many with access to both.. apart.

What is the chance you want to "jump on the grenade" for us and cut open the 2014 Driveshaft to check for any internal differences that are not apparent when assembled?? (or maybe a very accurate weight comparison of the two with collars removed??)



.

 

[LoudHandle]

…….. new machined upper and lower sprockets.
……...
What started this thread, is that when I pulled the 2014 jackshaft, I was shocked at how LARGE a diameter it is, I do not remember the 2013 being so huge. I just checked the part number, it has changed…….
Chris

The only change to the sprockets is the bottom, the top sprocket remains the same; according to the online Fiche. So I'm doubting machined sprockets, although that was the rumor everyone was hoping to be true.

As to the jackshaft, the only change identified to date is the sprocket threads are relieved and the threads start further back in the shaft. Necessitating a longer bolt and allowing more bolt stretch, decreasing the point loading that causes bolt head head to shear off. I have not held one but would guess they have not changed the mid-span diameter (wall thickness? maybe) but not the diameter.

 

[Devilmanak]

I think the lower shaft is just tolerance changes.
You are right, the upper sprocketis the same part number as last year. And looking at them, they both look cast. Funny how Polaris tells us one thing, then it doesn't happen, then they change things that they never acknowledge. If someone would like to measure the OD on the jackshaft, I would be happy to compare. I could be wrong, but I HAVE held 3x2013 shafts and 1x2014 shaft in my hands, and from my memory, the od is changed.

 

[Devilmanak]

Devilmanak... Thank you for the great thread and for your insights.. not many with access to both.. apart.

What is the chance you want to "jump on the grenade" for us and cut open the 2014 Driveshaft to check for any internal differences that are not apparent when assembled?? (or maybe a very accurate weight comparison of the two with collars removed??)



.

Yah, not going to cut one up unless someone wants to buy it first, lol. I can get a weight on two of them though, I have 2013 shafts in the shop.

 

[LoudHandle]

I think the lower shaft is just tolerance changes.
You are right, the upper sprocketis the same part number as last year. And looking at them, they both look cast. Funny how Polaris tells us one thing, then it doesn't happen, then they change things that they never acknowledge. If someone would like to measure the OD on the jackshaft, I would be happy to compare. I could be wrong, but I HAVE held 3x2013 shafts and 1x2014 shaft in my hands, and from my memory, the od is changed.

Unless someone beats me to it, I will measure the '11, '12, and '13's I have on the workbench when I get home from work, and update this post with the bar numbers for comparison.

The '11 and '12 are 4" in circumference (left my Mic's at work) which calculates to 1.27324" (also can see the machining marks from the lathe, pretty rough)

The '13's I have are 4 1/32" in circumference which calculates to 1.28319" (surface finish is smooth, likely ground not turned from the finish)

Looking forward to what the '14 measures at.

 

[Rick!]

After parting both 2013 and 2014 Pros, I am noticing a LOT of part number changes between the two years that Polaris has not acknowledged. (I read the post below about Polaris' solution to drive issues and they did not mention a few things.) To their credit, that seems to be their policy, on and off the race track. That is marketing, I am sure all manufacturers are like that. They do NOT like to acknowledge fault or product failure.
Everyone by now knows that the 2014 has a new quick drive belt, and new machined upper and lower sprockets. The backer plate is the same. The general consensus on failures (from Polaris) is lack of break in, which I am starting to seriously doubt. Yes, the 2013 sprockets were cast and a little rough, and would smooth out with some break in, and yes, (maybe?) the belt needs heat cycling to toughen up.
What people have ACTUALLY found is that when the belt rides against the upper sprocket lip, it gets hot and fails. (Do to misalignment, bolts coming loose, bearings going bad, etc.)
What started this thread, is that when I pulled the 2014 jackshaft, I was shocked at how LARGE a diameter it is, I do not remember the 2013 being so huge. I just checked the part number, it has changed. This is telling me that the 2013 shaft was too small for the load and was flexing, so they made it larger. If the shaft flexes, the upper sprocket will angle down under load, and make the belt walk into the flange, causing heat and failure.
Another thing I noticed is that Polaris parts costs have skyrocketed for 2014. A large percentage, the qd belt retails for $200 this year. The pullies/sprockets are expensive, and the lower is not available from Polaris when I checked last week. Are they bumping costs to try to cover losses?
Thoughts?
Chris

Doesn't the parts catalog show a longer upper sprocket bolt this year? That would probably drive a new PN with a deeper threaded hole in that end..

 

[AK IQ Pilot]

Doesn't the parts catalog show a longer upper sprocket bolt this year? That would probably drive a new PN with a deeper threaded hole in that end..

Yes and in addition to that the upper Jack Shaft bearing on the Quick Drive is the same bearing as last year. That would mean that from the bearing out to the sprocket the Jack Shaft is the same diameter as last years.

I'm not saying the middle section of the Jack Shaft can't be a larger diameter but the part # change in the Jack Shaft may be for less than we think.

 

[Devilmanak]

I think you guys are probably right, the upper sprocket is the same, the QD backer and bearings are the same, and I am sure the TEAM clutch end would be the same. I did measure, it is 1.25" so that seems to be the same. I don't know why that shaft looks so different to me, maybe because as was said, it has better machining on it. I think it is a lighter color too, whatever that means.

 

[geo]

It could be, DevilM, you are looking at the Pro with different eyes this early in the season lol.

Every part on my 2013 was quality in my eyes. The problems some had, IMO, was some of the assembly problems. Things like glue holding and torque staying and maybe even some alignment things.

A stronger belt is good too but if you align the top and bottom sprocket (like you should do on most chaincase set-ups), make sure your QD plate stays glued (even if you add a couple of fasteners), make sure your torque stays on the pulley bolts (or the spacer-brake disc wears and loosens), you have a pretty innovative and dependable drive system.
I think the changes Poo made to improve the product was nothing major or hidden. Just a company that continues to improve it's product with obvious QC improvements needed. The '13 in season updates seemed to be enough and the '14 changes are just to make it better without issuing in season updates to force the owner or dealer into more maintenance or visits.

 

[Devilmanak]

Agreed. And people can bag on the "HP ratings" all they want, my 2013 Pro was faster in every way than either one of my 2013 Doos.

 

[Dirty Steve]

Wouldn't the belt drive be more durable if the brake was located on the drive shaft instead of the jackshaft?
This way the the inertia that the belt is withstanding when braking is that of the jackshaft and secondary clutch rather than the entire rotating mass of the driveshaft and track.

Sent from my Droid Razor Maxx using Tapatalk

 

[volcano buster]

You may be correct about the disc being better located on the drive shaft. I think it would be helpful on the day that the belt breaks, but the diameter of the disc would cut into ground clearance under the belly pan.

 

[Devilmanak]

And it makes it more complicated. Polaris Pros are light because they are very very simple. I can get a track out of one in 1/2 the time of a Cat or Doo because of the brakes.
Also, after riding Cats and Doos, their brakes are horrible compated to Polaris. Polaris brakes would about chuck me over the bars if I wasn't careful in high traction or in the air. Doo and Cat brakes always felt mushy and weak to me. Personal preference I guess. I like to one finger brakes, not have to use a whole hand to get them to work.

 

[Devilmanak]

I ordered a 2014 jackshaft for a customer after selling the takeoff one I had. I didn't realize that it is a TEAM part, that Polaris sells under their part number. Has the jackshaft always been made by TEAM?

 

[mountainhorse]

Team has a history of making many components for the OEM sled mfgs... They have made engine cases, clutch/driveline components etc for Polaris ... so that does not surprise me.


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