the drive splines are "greased for life" at the factory
unless you have reason to think a previous owner took the rear wheel off, wiped off the proper 60% moly paste and put axle grease on (which will ruin the splines in about 5000 km), there is no reason to take the wheel off just to lube the shaft drive
Yamaha did a really great job of making the shaft drive maintenance free - all you need to do is change the final drive 80W90 oil every 20k miles or so.
Un Fortunately.... a few VS650 bikes got out of the factory in late 1990s, that were not properly lubed from the factory, or mechanics early on were wiping the 60% moly lube off and putting axle grease on them, and a bunch of drive shaft splines were destroyed in the early 2000 year timeframe. Ever since then people have been skiddish about the "greased for life" claim, and want to lube all the splines everytime they have the back wheel off.
BTW, Its not necessary to take the boot off the back of the transmission to lube that spine - wipe the spline down when its off, put the proper new lube on it, and cram it back in.
Whenever you pull the back wheel off take a good look at the splines. If they look like new and the moly (turns back I think) looks good then put a bit more on the ones that are exposed, and dont worry about the rest, unless you just want to. If the splines are dry and show wear, then get to all of them and inspect and lube.
You also need to be concerned if you take your bike to 6 Finger Jim's Bike Shop to have the back tire replaced. Anyone that is not familiar with shaft drive proper lube cannot be trusted. 60% moly paste IS expensive, some shops dont have it.
Last edited by KCW; 04-04-2019 at 10:38 AM.