you are forgetting to consider the value of your time, compare apples to apples, not apples to oranges, I have detailed receipts for both 2 and 4 wheeled vehicles all serviced by a professional mechanic, you are only considering cost of partsI know this thread is old, but I saw this and got to wondering.....
So I just ran a cost per mile calculation for my 2008 DL650, which I bought with 35,000 miles on it in January. It currently has 52,000.
Fuel (50mpg @ 2.20/Gal
Oil changes ($20 every 3000 mi - including filter)
Front tire(11k mi @ $76)
Rear tire (12k mi. @ $150)
Chain/sprockets (20,000 mi @ $140).
Insurance ($103/year @ 17,500 miles this year so far)
Total: 8.1 cents per mile. Insurance is a maximum, as that mileage figure will go up.
My 2005 F150 gets 15 mpg. At a fairly low $2.20/gallon, that's 14 cents a mile for fuel alone.
minor service done by a professional mechanic takes 1-1.5 hours to change oil, check fasteners, clean and lube shift linkage, cable operation, etc.
tires to remove wheel from bike, mount and balance tire, reinstall wheel is nearly a hour etc.
maybe your time is worthless, mine isn't
also consider coverage on your insurance, do you have same deductibles, coverage and limits ?
if you don't consider these things, your fooling yourself