Bolt on bottom chain case sprocket won't stay tight

[torkd]

The bottom chain case sprocket bolt on my 2014 ST won't stay tight. For the past two days I've had to tighten it 2 to 3 times a day, adding lock tight every time. What's going on? Didn't have any issues last year.

 

[M5-]

Do you have the update kit, it comes with a mechanical positive lock system. You could probably just get the bolt and washer from TS. Are you using red Loctite?

M5

 

[Uncle si]

That is the story of my horse experience. I check all four bolts every 2 hours and find them loose 1/3 of the time. I added low profile lock washers, but contacting the cover spins the left side bolts out.

 

[dirtrebel]

if the sprocket key starts to get sloppy then the sprocket can move enough to take the bolt with it, it only loosens itslef due to the direction of rotation. every time you get on and off the throtle it will loosen that bolt.

 

[the gman]

The keys I have checked on the new bearing kits I have installed are .002 thousands smaller than the .250 cut key ways. Keys I tried to get at north 40 are also to small. True .250 keys I get at the metal shops. New keys that come with new bearing kits and new 15 kits have shorter keys so the lock will work. Wrong way in my opinion..garry

 

[CATSLEDMAN1]

a fix

on the sno bike kits Dan and I built we used 1/2" fine thread 1 1/4" long bolts with red Loctite, 3/8" coarse stock ok when things are perfect.

I have hand drilled and tapped the 3/8" holes to 1/2 fine thread while everything was assembled on the bike.

 

[Chadx]

So how common is this? I just changed my bearings on my 2014 kit (only replaced the bearings and decided to not install the double-bearing upgrade kit this year). Now I'm a bit concerned. I have not gone for the first ride since the change. Timbersled has not published torque specs that I could find so guessing that is why the red loctite. With proper torque, I would think blue loctite would suffice without the pain of using heat to release each time the bearings are changed.

This first change, each bolt took 10 to 15 minutes of heat and a 1/2" impact to get loose. For one of them on the driveshaft, i had to put it in the vice, heat it so hot the grease was dripping out of the bearing and smoking. 20 minutes of trying to heat up the bolt with propane torch and 1/2" impact wrench every 5 minutes and finally got it off. Scary trying to get them off the first time.

Now it sounds like some are having the opposite problem and they are coming loose. Is this due to under torquing? Using no loctite or blue loctite or not enough red? Or some combination? (Edit: or, as mentioned below, should we be loctiting the bearings to the shaft as well?).

I want to know what is NOT working in the above mentioned instances so I don't repeat the mistake. I used blue loctite which has never failed me on other bolts. Maybe I need to pull out the bolts and do over with red loctite? Anyone using blue successfully and if so, what is your torquing method? And for those with the bolts backing out, please share your tightening process details to expand the wisdom of the group. Thanks.

 

[9Miler]

bolts are not losing up bearings spinning on shaft which wears soft spacer and there is no shoulder support on hex were they machined bearing shoulder this causes clearance so washer will spin loctite your bearings and sprockets on torgue your bolt to 70 ft lbs

 

[Chadx]

You are saying put red loctite on the shaft before sliding on the bearing? I didn't do that. Only loctited the shaft bolt in. (This is on the 2014 kit with only replacing the bearings and not upgrading to the double-row bearing kit).

Is everyone putting loctite on the shaft before putting the bearing on? Or only loctiting the bolts?

 

[9Miler]

use the green bearing mount loctite put on sprocket and key to

 

[torkd]

use the green bearing mount loctite put on sprocket and key to

This would have been nice to know when I did the bearings last season. I guess I'll be ripping back into it before I ride again.

 

[PalousePoo]

Torkd, I suspect your drive axle is undersized where the brgs mount onto it. I found mine was, when I did the double row update kit. The update kit comes with a new shaft, so the new brgs slide on tightly. I recommend you do the update. You can try to use loctite brg mount between the shaft and brg, but it wont hold if there is much slop. I am happy with the new locking system for the shaft end bolts. It is working just as its intended to do.