I particularly like the fact that you calculated the amount of maintenance costs attributed to actually commuting. A lot of people skip that.

I would like to comment on a few things.

* Food
You are calculating the amount of gas you save by not driving, therefore you should probably calculate the amount of extra food you have to consume to bike. For me, this wouldn’t be much as I haven’t changed my diet by bike commuting. I just eat a little more oatmeal in the morning before I take off. If you are scarfing down $4 power bars as suggested by another respondent, than you should definitely include this cost in your calculation.

* Car maintenance savings
I feel like you are really low here. If I read your calculations correctly you have only figured in gas saved, car-depreciation avoided, and oil changes. However, the true cost of driving a car per mile is much higher because you are wearing out tires, drive trains, windshield wipers, etc.

Here are some links:

http://tinyurl.com/6ya7v
http://tinyurl.com/9yrur

Basically, you should be able to google around and find a more accurate number for this. I believe that it will be quite a bit higher, perhaps even $0.30 per mile.

* Car insurance
Can you drop coverage? For instance, can you go from full coverage to just liability? This may or may not work for you, depending on how much other driving you do, but if you can, it could be a huge savings.

* Health benefits
I would continue to leave these out. You’ve done a nice job of trying to compare only items that can be quantified between the two modes of commuting transportation. These numbers are very strong and easily make a defendable point.

If you add in health benefits, in my opinion, you will have to start getting pretty deeply into the realm of probability. My wife is a public health nurse and we talk about this a lot. Nobody has a real good grip on the protective health benefits of weight loss, gain, blood pressure, etc. Studies argue about whether it is good to be a bit under weight, or maybe five pounds over weight.

Unless you have a specific health problem (obesity, etc.) that you are addressing via the bike, I would stay away from this argument.

Just my $0.02, nice study, thanks for sharing.

Regards,
–kermit

I bring that up as a NYC’er whom has thought about the comparison of costs -bike/car. If I were to buy an affordable car, the cost of all the above yearly would probably exceed what I’ve spent on my Dahon Jetstream XP (an expensive folder) 5 times over.. and that’s per year.

Riding my bike isn’t cheap (and is not fun for much of the winter), but compared to the cost of a car, I’d do better riding the bike when it’s nice and _renting_ a car on the terrible days.

Also, don’t be so sure that your insurance costs are fixed. It’s not a huge difference, but annual estimated mileage is often included in calculating premiums. See if you can get a new rate quote based on reduced commuting mileage.

AFAIK, the IRS rate is now $0.48/mile.

I also did some calculations on the cost of bicycling — I don’t commute by bike (I walk), so it’s all recreational riding. As of this moment my cost is about $0.49 per accumulated mile; you’re running $0.26, but I did include “capital” costs.

See http://reidster.net/logs/bike.html if you’re interested — click on “Cost per Mile”.

Reid

Think of all you’re saving in medical bills because you’re fit. Plus, mental health is worth more than it’s possible to determine in dollar value. Just imagine how much higher your blood pressure would be if you drove every day. [g]

As for car insurance, you sure you can’t get a reduction in your insurance if you’re a bike commuter?

If you were going to participate in these events, anyway, I think some of your cycling costs are going to be incurred whether or not you’re commuting. If you’re going to riding in centuries and tours, you need to get in a certain number of miles a week. So, you’d just be riding before/after work, and still wearing out various bike parts, AND you’d have to pay for all that gas and so on.

The real question is: does someone save who is not a recreational cyclist? Let’s take my next door neighbor, who, to my shock, has taken up a multi-modal commute this fall. She rides a mile to the bus stop, uses her company-sponsored bus pass to get a ride to Montlake and puts the bike on board, and then rides a couple of miles to her workplace. She’s riding a 20 year old mountain bike that was a garage ornament before. Total investment to date: $35 on a new bike helmet.

As for the economics of cycling, toss the health benefit variable into the equation. Hmm, and what about food? Jeesh, there are so many variables.

Wheel building… you must buy the wheel building bible “The Bicycle Wheel” by Jobst Brandt:

http://www.amazon.com/exec/obidos/tg/detail/-/0960723668/qid=1129222199/sr=8-1/ref=pd_bbs_1/104-4132611-5226340?v=glance&s=books&n=507846

With that book I have built at least 12 wheels.

As far as the clothes, I wear a t-shirt and gym on my commute, unless it’s cold, where I’ll go with tights and a jacket. I only use my jerseys and padded shorts on stuff over 20 miles.