Getting a garaged 2008 KLR which has not run in 4 years. What should I do other than changing the oil and fresh gas?
Did you inquire as to 'Why' it was parked?
First thing that I'd do is give it a bath, (plug the fuel & vacuum hoses to the carb) especially under the gas tank, top of the engine, around the spark plug cavity, under the seat & under the fenders.
Next I'd remove the air box door, check for mouse nest, confirm that the air filter had been re-oiled by the last person. A dry filter does Not Stop the dust! Remove the air filter & inspect the back side & inspect the flame arrestor screen for previous dusting. Clean & dry the air filter, sometimes old filters fall apart during cleaning. Thoroughly re-oil the air filter.
With the spark plug Cap removed, I'd confirm the spark plug cavity is 100% clean & the drain hole which comes out from under the thermostat housing is open (use a wire to wiggle thru). Now you can remove the spark plug to inspect & squirt some WD40 or engine oil into the cylinder. If you have a compression gauge, check the engine cold cranking compression with the throttle wide open. Minimum spec is 75 psi.
Drain the carb, using a remote fuel supply refill with gas. Attempt to start & run, this will show whether or not you need to remove & clean the carb or not.
Bleed fresh brake fluid thru the systems.