Gentlemen:

Many thanks for all the advice on the '85 K100 project, "Alda" (I rescued her last year from PO in inoperable condition).  

I'm a day or two (and a battery) away from trying to start her up after a significant rejuvenation.  I'm curious if there's any advice for running her for the first time in three years.

I had the bike completely apart -- except the engine -- to have the frame powder coated and to clean and inspect everything else.  In the process, I did spline lube (splines looked great), oil and filter change (no metal flakes or any other signs of engine damage), new rear rotor and rebuilt front and rear calipers, and many other things.  Transmission and final drive fluids, as well as coolant, were changed and nothing untoward noted in the old.

Side note:  Today's project was brake fluid.  Front filled and bled quite straightforward.  Rear was not so easy.  I consulted the forum and found that syringe or vacuum pump was the ticket.  Having no syringe and no obvious way to make a mechanical pump for suction, I was inspired by Apollo 13 (the CO2 scrubber fix) and created a slip for the end of an actual vacuum (i.e., for floors), attaching it to a length of hose and to the bleeder nipple.  Turned on vacuum and, viola, brake bled.

Anyway, I replaced fuel pump and filter; checked air filter, replaced vent hose.  I examined fuel line from tank to fuel rail, which looked fine.  I did not remove the fuel rail and otherwise haven't touched engine internals.  Based on everything else I've done on the bike it seems to have good bones, so I didn't feel the need to start making the project more difficult.

So, bike hasn't run in several years.  Anything you'd do to prime for first start?  Squirts of oil, fuel, turn over, checks, etc.?

Many thanks,

Frey

Providing that you are not using some old 20/50 1970's oil then you should just start it up without throttle, any oil will circulate quickly if it is modern stuff. 
BMW also say that you should not warm a bike on tickover, but ride it to warm the oil.

I've brought lots of Ks back to life after long slumbers. You're probably OK just starting it up.

However, if you want to be anal retentive then here's what I do these days just to be on the safe side and not spin it up initially with dry cylinders:

0) Drain the fuel rail.

1) Pull the plugs and spray some fogging oil into each cylinder. Let it sit for a few minutes.

2) Put it on the center stand in 5th gear and then use a lug wrench on one of the rear wheel lug bolts to turn the engine manually before spinning it with the starter motor. (This will be much easier with the plugs still out.)

3) Expect possibly LOTS of smoky exhaust on the initial startup, possibly for a few minutes. This is normal and nothing to worry about. Being an 85, it's got the old rings so it's possible that much oil has seeped past the rings into the combustion chamber. If possible, roll it outside or at least have the garage door open with a fan going to deal with the smoky exhaust.

BMW does recommend not letting them idle, just riding off, but it won't be the end of the world if you do let it idle.  It will probably just foul the plugs a little if you do. It's OK to give it some throttle and run up the RPMs once you get it started.

I let them idle for several minutes, keeping on eye on the overheat light in the cluster, and waiting for the fan to come on to make sure that's working.  If the overheat light comes on before you hear the fan kick in then turn it off as you've got fan issues to deal with.

If you haven't replace the fuel lines then keep an eye on those too for possible leaks as there's a good chance that original fuel lines have dried and cracked over the years.

If it doesn't start then pull and inspect the plugs. If they're dry then you may have one or more clogged fuel injectors to deal with.