dave: IMO.....and a week never goes by that a board member doesn't ask a similar question to yours....it is a complete waste of time and money stock-piling parts for any XB model. think of it in these terms: every single perishable on your firebolt will always be available thru the aftermarket. there are still literally hundreds of thousands of parts actively listed thru the H-D/Buell dealership network and the amount of demand/orders being placed for those parts surprisingly low. most all the sensors and fuel pump cross over to chrysler/ford automotive applications and will always be available. one other point of interest dave is this: i'm the largest vintage kawasaki parts dealer probably in the world. one of the most prized and coveted vintage jap models in the world
There are a couple original oem cosmetic parts I am planning on stock piling, but like John said, nothing to worry about. Especially the parts to keep it running, it's a Harley engine, with common sensors.