Yes, TCO is a totally different figure; greater in value. However, the variables become rather cumbersome and more so than your example. What new auto cost are you going to use for the comparison; BMW M6; Volvo S60; AMG; Ford Ka; Fiat Punto; Kia? You have to allocate costs for items that last for years over multiple vehicles such as riding gear: my Aerostich has seen 100,000s of miles of riding, boots can last for years as do some gloves. And the other items you mention such as salvage value. But not done yet. Have to adjust everything to current year dollars or at least same year dollars (typically a future year) before doing the cost per mile calculation; another pain. And what mileage will you use. I've kept bikes to 100K miles or more like yourself; people trade in cars every couple years at less than 50K miles. For an equal comparison of "TCO per mile", would you not use the same assumed total mileage? So I wonder if the NC will end up being more or if so, insignificantly.
So yes, I can do lifecycle cost calculations also; but it's a pain. So I addressed operating cost as I thought was the topic.