Some links to browse do a search for "quickdrive" or "belt drive" and you will get lots of details.
In fact, there were enough posts on the 2013 Quickdrives that for that season... I created a separate sub-fourm section dedicated to strictly the quickdrive.... which I merged back into the PRO forum in 2014.
Most of the issues were caused by defective drive shafts IN 2013 Model Year (MY) ... for the 2014MY there were improvement in the belt and drive shaft.
Updates were put out by polaris for the 2013 MY PRO RMK's... a driveshaft collar and pulley bolts.
There were some good write-ups on here about checking bearing clearance but I could not find them this moring... I only have a few moments to look and have to get back to work... but they are out there... Checkcking bearing fit on the jackshaft and driveshaft are big ones... In 2014, there was an improved belt.
Also..IMO...invest in the correct tools to install the drive belt... sure, you can get it on without it... but, IMO, not the best idea.
Also, IMO, a good idea to put a full coverage collar on the driveshaft on the endo f the driveshaft on the side with sprocket attached (no need to remove the driveshaft)...of the 2013's and move the factory collar to other end.
Not a bad idea to add a belt tensioner from Fire N Ice or TKI for good measure.
With the updates and a new 2014 belt... you should have no issues.
from a post of mine in 2013
While the majority of people have not had QuickDrive® belt issues, there Are a significant number of people that did and do have issues of belts failing prematurely.
To say that the QD is trouble free OR to say that it is fraught with issues ... would not give an accurate "picture" of the situation.
It does seem to come down to luck of the draw. If the unit is out of warranty, I would install a full-full circle/capped shaft clamp and do some reading in the Quick drive section on issues like bearings on jackshafts & Driveshafts, soft adhesives, driveshafts out of true and/or running a steel drive shaft.
It does seem to come down to "luck of the draw"... you have a really good chance of getting one that is trouble free... and a lesser chance of getting one with issues.
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The 600 you have would benefit, IMO from gearing down... heck... the 800's run better with gear down as well IMO.
http://www.snowest.com/forum/showthread.php?t=346037
http://www.snowest.com/forum/showthread.php?t=339999
http://www.snowest.com/forum/showthread.php?t=333103
http://www.snowest.com/forum/showthread.php?t=332337
http://www.snowest.com/forum/showthread.php?t=323799
http://www.snowest.com/forum/showthread.php?t=344815
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