R
rmscustom
Well-known member
I think there was 1 failure with a steel shaft.
650 miles on mine with the steel shaft put in at 1 mile. My stock shaft had visible runout where the steel shaft apears to run very true.
QD Belt Temps Field Testing
- Thread starter AK IQ Pilot
- Start date
I think there was 1 failure with a steel shaft.
650 miles on mine with the steel shaft put in at 1 mile. My stock shaft had visible runout where the steel shaft apears to run very true.
Yes with the steel shaft... Had a friends PRO that I installed a Steel shaft on shred a belt.
Some of them are not true... I'm getting old and Cant remember sh!t.... but another member posted his results on the trueness of the steel 2012 shaft he installed.
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A little JFYI....turbo next to belt is showing temps upwards of 300 at the belt....and yes, losing cogs.
A
AK IQ Pilot
Well-known member
Yes. Sled #1 in the Opening Post had a steel drive axle installed at .5 miles and sheared half the teeth on the QD belt at 55 miles. Next belt is at 155 miles and looks very good so far.
Wow, 300deg belt temps is serious. Wonder if anyone with a C3 or CMX drive has taken temps of their belt and upper pulley.
Originally Posted by winter brew
A little JFYI....turbo next to belt is showing temps upwards of 300 at the belt....and yes, losing cogs.
Is the Belt showing 300 degree temps or the Turbo housing??
Even the chaincase should not be subjected to that amount of heat load. Do yourself a favor and build a heat shield, and in the future demand that the builder of the turbo kit provide one. It is not Polaris' fault you installed a bomb right next to your quick drive. Get a clue dude! Quit Bitch'n about something that you fully brought to bear on your own.
LH... I don't think that WB was saying anything other than a turbo PRO showed belt temps in that range... and would probably agree with you on the heat shield for Turbo applications on the 2013 PRO RMK's... I know I do!
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Sorry. My bad for just sharing info on belt temps, I thought that was what this thread was about. And its not my sled and I didn't design the turbo kit, not sure where you got that idea.
The sleds made it for several rides so it shows just how much heat the belt really can take. I dont think the majority of the failures are heat related but obviously it played a role in these particular failures.... 3 of them on 3 different sleds.
WB, My apologies also, I made some assumptions from reading your posts. Yes, this is the place to post that information. While my verbiage may have come across as directed at you, it was a message intended for anybody that is generating any temps approaching 150-160ish degrees under normal riding. If the turbo or anything else is throwing that much heat, then countermeasures need to be taken!
Also those having belt issues and anyone who wants a trouble free ride; need to be checking the upper bearing alignment and the sprocket / pulley attachment bolts (as Geo has referenced in the "recall?" post). Sounds like a few of the Jack shafts are spinning inside the bearing as soon as the bolt tension / torque is lost.
These two may not cure all the woes of the QD but they surely can not hurt.
Is the jackshaft bearing replaceable with the old style with set screws? I haven't had a QD jackshaft out (yet). It must not be a press fit?
From Geo's write up it is a sloppy slip fit (about 1 thou clearance) standard NTN 6205? chain case bearing. So it appears that they used a quality bearing just overshot the shaft tolerance, a little Loctite wicking stud and bearing mount would likely be to our benefit. He also found that his had spun enough to self machine the brake hub to fit the bearing radius and that the bearing retainer plate relies on the top bolt torque to locate the top of the bearing plate and maintain the spacing. Which in turn causes a sizable side load on the bearing which in turn may be why the bearings are starting to fail and the Jack shafts are being spun in half from spinning inside the bearing as it works loose.
The above comments are from memory so feel free to search or attach his exact comments.
G
geo
Well-known member
IMO there is nothing wrong with the fit of the parts (slip fit is slip fit) or the design. Clamping the inner race is a common design in all chaincases (except the '12 PC and I don't want to go there again lol).
IMO it is the disc brake and it's use causing the loss of torque on the inner race. the disc material is soft (cause it has to be), it rides on splines that have clearance so apply the brakes hard and it will try to work loose eventually (I don't use it in reverse anymore lol). And,, Poo tapered the clamping edges of the disc too much (mine was only 60 thou).
IMO that is why some shafts have spun. The disc wore 'til loose from use lol, and then the shaft spins in the bearing. As long as you retorque a couple of times it may all be good.
This is the heat thread. After a bunch of rides now with my repair and jackshaft shimming, I,ve cured my top pulley heat issue IMO. I believe my heat was generated from side load on the jackshaft bearing there because of alignment problems in MY chassis (that doesn't mean all will be the same).
For about 800 miles my top pulley was always the hottest thing in that area and as best as my fingers could tell it came from the shaft to the pulley. It would take sometimes as many as 4 or 5 handfulls of snow to cool because it was sizzling hot. Even with only tree riding.
Now, in order of warm to hot; it is belt, bottom pulley, top pulley, outside of disc towards the can. There is probably only 10ish degrees of difference between the top and bottom pulleys now.
I've found the faster you go the greater the heat (I think it is all from the can) in that area but none of the belt drive ever gets to sizzling hot anymore.
I don't think I will do another project in this area this year ('cause it's working as I expected from the beginning now lol) but if I did it would be to exit the can heat.
Deflecting the heat for a short distance is no biggy but getting it out of that area is the real trick. I,ve drilled plenty of useless holes in the past lol.
IMO it is the disc brake and it's use causing the loss of torque on the inner race. the disc material is soft (cause it has to be), it rides on splines that have clearance so apply the brakes hard and it will try to work loose eventually (I don't use it in reverse anymore lol). And,, Poo tapered the clamping edges of the disc too much (mine was only 60 thou).
IMO that is why some shafts have spun. The disc wore 'til loose from use lol, and then the shaft spins in the bearing. As long as you retorque a couple of times it may all be good.
This is the heat thread. After a bunch of rides now with my repair and jackshaft shimming, I,ve cured my top pulley heat issue IMO. I believe my heat was generated from side load on the jackshaft bearing there because of alignment problems in MY chassis (that doesn't mean all will be the same).
For about 800 miles my top pulley was always the hottest thing in that area and as best as my fingers could tell it came from the shaft to the pulley. It would take sometimes as many as 4 or 5 handfulls of snow to cool because it was sizzling hot. Even with only tree riding.
Now, in order of warm to hot; it is belt, bottom pulley, top pulley, outside of disc towards the can. There is probably only 10ish degrees of difference between the top and bottom pulleys now.
I've found the faster you go the greater the heat (I think it is all from the can) in that area but none of the belt drive ever gets to sizzling hot anymore.
I don't think I will do another project in this area this year ('cause it's working as I expected from the beginning now lol) but if I did it would be to exit the can heat.
Deflecting the heat for a short distance is no biggy but getting it out of that area is the real trick. I,ve drilled plenty of useless holes in the past lol.
Geo - we would LOVE to see a picture of your shaft-shim. Pictures are worth a thousand words.
I've also noted a staggering amount of heat in my upper pulley, but its not consistent at ALL - in fact its fairly rare. Sometimes its there, but ususal my upper pulley is just warm to the touch? Very strange. Would make sense that a highspeed/highload trail rip might be causing the shaft to spin in the bearing causing excessive heat build up from the added friction. Going to check my bolts tonight. Wondering if those us of us that are aggressive with brake in techincal riding might be causing more "loosening" of the tolerances due to our riding styles? I don't know about you guys, but i use my brakes a ton in technical riding to whip tracks speeds up inorder use the gyro effect of the track, and then quickly curb tracks speeds once i've got the sled in correct position/angle. Gotta think my style might not be helping this issue.
yet ONE more reason to put the brake on the driveshaft!!!
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