I had some communications with a guy who is looking at greasing his shaft drive splines, the ones where the propeller shaft engages the gear case, not the ones on the wheel. 

My question is how many of you have ever removed the gear case to lube those splines, if ever?  I know the wheel splines should be lubed because they are at more risk of exposure and drying out since the seal is actually at the hub shaft and can get dirty water in there around it.  The propeller shaft is another story, being fairly well sealed and shrouded up in there. 

The rider is on a KZ1100 that has 27,000 miles.  Seems there should be no issue.  Clearly it is up to him and I'm not trying to talk him out of it.  It's just that after 22 years in and around a shop I've never seen the actual shaft splines go bad on any Jaanese bike.  I've heard of it on BMWs, but not on Japanese bikes.  Any comments?  I'm just curious, not out for an argument.  I figure the Concours 10 would be the riders with the most miles and experience giving some credibility to what is said.

I grease the shaft splines every tire change, if for no other reason than I take off the final drive to ease the rear wheel out.

Those splines need grease, they slide under load when the swing arm moves up and down.

I grease the wheel ones too if only to prevent rusting.

Is there a coupler in there too?  I saw the breakdown on Kawasaki Parts for the KZ1100, didn't look to see if the Concours was similar.  It looked like there may have been some loose parts that had to be fitted when taken apart.  Maybe the illustration just looks more complicated than it really is.  Regardless, thanks for your comment on it.

I grease both ends and the wheel splines with moly.