[johnd]

As Murphy always says.... If you are going to have a major break down, it will happen in the worst place furtherest from home base.
This has happened to me for the second time in the bikes 8 year life. The 24mm nut securing the variator assembly has worked loose, resulting in the outer drive cone working its way out into the casing, grinding itself to bits.
I have been aware of the problems that can occur when tightening this nut, ie. belt interferance, and have always added a drop of LOKTITE to ensure the nut doesn't work loose. But it happened again.
I have studied the damage and noted the fretting marks on the steel drive plate which indicates movement. Also the serrated/splined centre hole on the steel drive plate is almost chewed out. No matter how hard you do up the nut, radial shock loads will in time overcome the resistance and allow the plate to move resulting in the assembly loosening and spline damage. Unfortunately there is no tabbed washer and slot to secure the nut if it had been designed properly, only the use of thread lock which is not up to the job.
I recommend that when you have to replace any part of the variator assembly, tighten the main nut, followed by thread lock and another lock nut. There should be around 4 threads left on the shaft, just enough room for this purpose. Had the nut not moved, the clearance caused by fretting, the spline on the steel plate would have chewed out and destroyed the main engine shaft. New Engine. May be I'm lucky?? jD

 

[Scootereno]

Wow! Sorry to hear about that.
I keep a grease pencil mark on both the variator and clutch nut/shaft for a quick visual check every oil change when I blow out the tranny and filter.
I also used an impact wrench to put those nuts back on.
Locktite has yet to fail me...knock on wood.

PS- I love New Zealand. Spent some time touring your country a while back and fell in love with it.
I went snow skiing in the morning and was at a beach that evening. One of the few countries I could move to and stay.

 

[TwoWheelTim]

Sorry to hear of the failure. Hope you get it fixed soon.

I had an axle nut give me a bit of problem once. Here are a few steps I took that have worked ever since.

I found that cleaning off the threads and applying loktite blue to the shaft and torquing the nut with an impact wrench.
Next I use loktite green and apply to the outside of the nut where the axle shaft protrudes out. This green stuff is designed to wick in and lock per-assembled fasteners.

Good luck.

 

[Daboo]

I wonder if you put on the Belleville, or conical spring washer, correctly? The variator washer looks flat, but isn't. The design of the washer puts a preload on the nut when you tighten it down. There's a good explanation at Wikipedia. http://en.wikipedia.org/wiki/Belleville_washer

While I'm not saying you shouldn't use loctite, I've never used it before on the variator and clutch nuts. Between the two 400s, I have over 75,000 miles on them. I'd think if it was going to come apart, it would've by now. (Mine will now disintegrate on the freeway on the commute home tonight in the wind and the rain.)

Chris

 

[Aladinbama]

While I'm not saying you shouldn't use loctite, I've never used it before on the variator and clutch nuts. Between the two 400s, I have over 75,000 miles on them. I'd think if it was going to come apart, it would've by now. (Mine will now disintegrate on the freeway on the commute home tonight in the wind and the rain.)

I was going to say something similar. I don't have 75K on Burgmans, but you'd think by now ...
Anyway, I didn't want to tempt the variator gods.

 

[Badgator]

well i've looked at both nuts n washers abid there from 2004 that old i went ahead and order brand new ones,just to start off fresh this way i know if the bellville washer will be right thinking of changing my variator to a jcosta but don't know yet we'll see

 

[Elliott Larron]

A simple Remedy i used was just Plain old 99cent super glue, works every time keeps the screw Stiff and from working it's way out, been using this Remedy for years.
last time i had that kind of failure was when i used my hand to tighten the NUT, Now i use the torque wrench.

Elliott,

 

[Daboo]

You might want to rethink moving to a JCosta, and find out why your current set up has failed.

The JCosta has a reputation of failing. I don't mean just a bit, but catastrophic failure. Even if it works as advertised, the weights wear quickly and will cost $$ to replace.

Chris