This should be the first plug pulled during the Vulcan's 600 mile check but few dealers shops even seem to know about it much less use it. Owners have reported finding things in the screen ranging from bits of gasket to metal to a zip tie and even a plastic bag.
What is it and where is it? Check the diagram below (courtesy of Kawasaki) which shows part number 16097 (bottom right in the box). That's the screen which 'pre' filters oil before it reaches the oil pump and spin on filter. It's also the best oil drain you have with the opening sitting lower than the normal oil drain plug in the center of your crankcase.
To find the plug which holds the screen in (part #11012) look on the left side of your crankcase, roughly midway between the kickstand and the oil drain plug on the bottom. On the 'side' of the crankcase is a 17mm plug. This can be removed with the bike on its kickstand or on a lift (easier) or by using the leveling method detailed on another page. Remove the plug, (check for damage to the gasket and replace if necessary) remove the spring, remove the washer (part # 92022) and carefully slide the screen out of the opening noting its orientation. The neoprene washer (part # 92071) will probably stay attached to the screen. Don't lose it. Clean the screen with solvent if you have it, degreaser if you don't. When all the oil has drained from the engine and the screen is completely dry, re-assemble in the reverse order.
After the first removal and cleaning it isn't likely you'll find anything else in the screen for a long time. Many owners use this method to drain oil every second or third time just to check the screen and make sure all is well inside the engine. Metal shavings (after the first cleaning) could be something worth mentioning to your shop.
29 Screen w Spring & Washer
From Chilton's Vulcan Maintenance Book
Top: A points to screen location (B = Front)
From VN1500P Service Manual
Click Photos For Larger Images
From the VN900 Custom service manual:
Note that the orientation may be different for the 800 and 900 bikes, specifically the screen may be installed with the end cap facing inward. Double-check how the screen is facing when you remove it.