2007 Apex GT, Jackshaft bearing collar pulled through the bearing?

[97mach1]

A few years back, I changed my jackshaft bearing (clutch side) with what was supposed to be a new OEM Bearing, collar, and nut. I don't remember seeing any issues when I changed it however upon doing my pre-season, I noticed play in the shaft. Further inspection revealed that the collar (with the nut still on it) had somehow pulled through the bearing and the collar/nut assembly shifted toward the chaincase essentially leaving the shaft to be "floating" on the clutch side and wore a grove in the jackshaft presumably from flopping around against the bearing. Surprisingly I don't see any further damage as I know a few miles have been put on not knowing the collar pulled through the bearing.

My question is: has anyone else seen this happen and any idea how this would have happened?

Again I am pretty sure the collar was holding tight to the bearing and shaft as it should when I changed it. Bearing was supposed to be OEM but will have to check it for taper...

 

[Simplespeed]

Based on your description, I would be inspecting the secondary clutch, and the top gear and chain for possible problems causing the unwanted stress on jackshaft… If bearing was correct you may have other issues going on ….

 

[MrSled]

You sure the locking collar isn’t what you are seeing ? Maybe a picture would help.

 

[Redbeard]

Just speculating...

I'd say the ball bearings are gone on the jackshaft bearing behind the secondary, which allowed the inner race of the bearing and lock collar/ nut to shift inwards towards the chaincase.

In what order did you re-assemble the chaincase and jackshaft?

Assuming all the parts are in the correct position, you need to tighten the large nut on the jackshaft inside the chaincase first.

Backing up a little...

There is a circlip and steel washer on the jackshaft that come against a collar, which butts up to the outside of the upper chaincase bearing (circlip, washer, collar, then bearing). This is what actually sets the jackshaft location side to side.

After the chaincase side is done, then you can tighten the collar and nut behind the secondary. If not tightened in this order and/ or there are missing parts, you will side load the secondary bearing and it will fail. It can also side load the upper chaincase bearing.

 

[RobX-1]

Not sure if you will get a reply from the OP as this post was created in Janauary of 2022

 

[Redbeard]

Not sure if you will get a reply from the OP as this post was created in Janauary of 2022

Yup. Missed that.