Busted bolts

05765scott

Active member
Joined
Nov 18, 2009
Messages
85
Reaction score
17
Location
fort mcmurray
Anyone figure out why bottom quick drive bolt breaking? There should be no side load on the lower pulley so why my bolt break?
 

Attachments

  • image.jpg
    image.jpg
    168.1 KB · Views: 325

CamoKVF700

Active VIP Member
Joined
Mar 25, 2008
Messages
729
Reaction score
1,797
Location
Sherwood Park
Could only be a couple things if there is no side load.

Improper bolt material for application.

Or lack of lock tight causing the bolt to loosen off enough that the on and off shock loads of the throttle are causing them to snap off.

Or under Torqued / over Torqued for application.

Is there wear on the pulley? Wear on the pulley to bolt face can cause lack of clamping pressure acting like a loose bolt scenario.

Sent while wishing I was on my snowbike
 

chemmod

Active VIP Member
Joined
Feb 4, 2009
Messages
215
Reaction score
251
Location
The Crazy Cold North
How many miles did you have when it broke? Mine had roughly 1400miles.

I wonder if there is any correlation between mileage and failure?
 

Lund

Active VIP Member
Joined
May 4, 2013
Messages
4,247
Reaction score
11,288
Location
Vernon/Kelowna
Bolt over torque is the #1 reason that the bolt would break.
This might be because somebody did not torque it properly at a shop, most common. I have seen this in chain drive numerous times.
Or not as common but wrong bolt used for the application. It should be a grade"8" bolt that is torqued to spec with red loc-tite.

Another thing to look for is wear at the hub, if the splines are worn the bolt will never torque properly and the bolt can break.
 

05765scott

Active member
Joined
Nov 18, 2009
Messages
85
Reaction score
17
Location
fort mcmurray
Sled has 815kms never touched bolt sled bone stock except a can last sled was mod and decided to try a stock sled and not mess with anything. Four trips out two trips to shop, sounds like getting the run around from Polaris about warrenty on my upper structor. Cycle works is doing a great job on keeping me on the snow making tracks. The customer care is really good at cycle works just need the sled to hold together !!
 

Teth-Air

Active VIP Member
Joined
Oct 16, 2008
Messages
3,751
Reaction score
7,966
Location
Calgary/Nelson
Mine broke at 1200 kms with the TKI belt drive. The significance of this is that I know I torqued in when I installed the drive kit. That eliminates the likelihood that the factory just forgot to tighten it. So far the grade 8 bolts are holding good.
 
Top Bottom