G'day All
              I just removed the final drive to grease the drive shaft splines, and to my surprise as I was pulling the final drive from the swing arm the final drive thrust bush and nut fell out on the floor with a small amount of diff oil. After close inspection there appears to be no physical problems with the final drive unit. No bearing movement or back lash of any sort even the seal appears to be in great shape.
Has anyone else experienced this issue? And what would be the likely cause. On inspection the threads appear to have no lock tight residue on them. So my plan was to put it back together with lock tight on the thread. As this nut will need to be put back on with a tube spanner my question is how tight does it have to be? This bike has travelled a mere 24.000 km and I would be very surprised if the final drive has ever been off before. Any other ideas would be appreciated.
                     
     Smithy  

Hmmm. We shall all have to put on our new K bike thinking caps for this one.

I don't have a clue as my hat is still in the mail.
Ask me again on Monday

rossko wrote:Hmmm. We shall all have to put on our new K bike thinking caps for this one.

I don't have a clue as my hat is still in the mail.
Ask me again on Monday

         Funny that Rossko, I had my one on but the bloody thing isn't working!

The reason why this occurred is because you didn't wait for me to come around for the maintenance day we were talking about.
Re-attach at three empty beerbottle pounds per square inch.

It's a good thing that I didn't wait Sean, could you imagine two pissed nuts trying to guess where the lose nut came from. Anyhow I thought that I would get some practice, so I'm fit to help lift that heavy  wheel off your bike.

that nut is supposed go on extremely tightly ....more than one can do by hand without a massive extension bar and some way to hold it together .....I think sidecar paul made a bracket that attaches to the output drive hub .with 2 bolts to fit the wheel lugs ....for clamping in a vice ...so you can get enough purchase to wind it up to spec .....looking in the book says 200 nm ...

It's a strange thing to happen.

Thanks Charlie
                     It does make me wonder how it ever came lose, 200nm is almost 150 foot pound. If it was torqued correctly to begin with it should never came lose. Well I'll be busy making a bracket to hold it in the vice tomorrow. The next thing will be finding a deep enough socket to torque it up with.

Hi smithy,
Here's the tool that Charlie mentioned.
https://www.k100-forum.com/t3247-simple-bevel-box-locking-tool

Cheers,
Paul.

Thanks Sidecar Paul
                            That's a better idea than making a big frame, I'm trying to make my mind up weather to pull the bevel gear out and replace the bearings or just give the final drive a good clean , and torque the bush and nut back on. When I dumped the oil out it was grey with metal shavings and small bright bits of case harden steel by the look of it. There isn't any play and the bearings spin freely by hand with no noises. It sounds like I'm trying to talk myself out of this job, but the big bevel gear bearing is $200.00 and pin bearing $60.00 plus $40.00 seal, and I would have to buy a special tool to remove the collar retainer. It may be cheaper to find a good replacement unit to get the bike on the road for now and rebuild mine later.
   
                   Smithy

You should be able to get the big bearing for around $80 they are a fairly common size. Pull the back plate of the drive there are 8 socket head screws and you need to heat it to soften the loctite but then you can see the truth about the state of the gears.
I would be inclined to disassemble and clean it out check the running surface of the bearings and check with a light machine oil to see if it turns smoothly then put it back together with the pinion nut torqued properly and see how it goes by monitoring the oil comming out every 1000k for a while and if no flakes on the second change then leave the third lot of oil in there.

Thanks Rick G
                    I'm inclined to do what you say, It may not be as bad as I think. And if it doesn't work out the contact you gave me has a good final drive at a reasonable price, The only thing is the ratio is 32/11 not 31/11 as the one on the rs.

You will barely notice the difference as the top speed is only 10kph different from RS to RT