Huge thanks to Mark Lawrence who originally compiled this list and who hosts an excellent website full of motorcycle tips & tricks
The following information Applies To All Vulcan 800, 1500 & 1600 Engines
Note: The shorter 2.5" length is stock, 3.5" can be used after measuring to be sure your model has enough clearance. These filters can not be used on Vulcans that were subject to the factory oil filter recall and now have the canister style filter installed. That filter (until someone notifies me they've found a direct replacement someplace) Kawasaki is part number 99999-0032 which includes the oil filter element, relief valve and o-ring.
These Oil Filters have 20 x 1.5mm threads, 14 psi by-pass valve, anti-drain back valve, 2.3" O.D. gasket and are 2.5" to 3.5" long. (in this case longer is definitely better if you can get your oil filter wrench in the space.
A quick Gadget tip: Something you'll discover sooner or later (better sooner) it is actually simpler to reach and remove/install your oil filter from the left side of the bike. Check it out while you're removing the oil screen bolt.
Filters Specifically Marketed For Motorcycles
Highly Recommended Replacements
About 2.5 inches long
Best if your goat belly (pre muffler) is still installed, or you have a Hot Box
About 3.25 inches long
Better with aftermarket pipes or goat belly is bypassed and removed