Well, it all started with my idea to buy a Vespa, I live pretty close to work (4.5 miles) and I was thinking it would be more "green" to buy a small motor scooter and drive that in. Plus it would leave my car for my driving children to use during the coming summer. This is happening at the same time I am going through the requisite 46 year old mid life crisis - oh-my-god I weigh 205 lbs - start going to the gym 3 times a week period of my life.
It dawned on me that it might be possible to cycle to work, its only 4 or 5 miles.... Of course apart from the odd time on a stationary bike (not my favorite form of cardio BTW) I haven't ridden a bike more than 100 yards since my early twenties. After a bucket load of research and visits to LBS's I was stuck in the road bike -vs- hybrid debate (with a touch of cyclocross thrown in for good measure) I must of went back and forth three times before settling on a hybrid (or Trek's term, "fitness") bike. My end analysis was partially $$, concerns about traffic awareness and some concerns about lower back issues. Some $1,200 poorer I was the proud owner of a Trek 7.6 FX and assorted Helmet, bike locks, repair kit, sunglasses etc...
Today was my first commute in, I left ~9:00 am after nearly all of the quite busy car commuter traffic was over. I "cheated" by carrying/walked my (yet unamed) bike down an old abandoned, but still tracked, rail line to avoid the uphill double blind ess curve right by my house. The bed is all large rocks - not ride-able IMHO. I then joined the county road on the straight spot with good sight lines and set of. Flat for the first half a mile, a slightly tricky light with a left turn lane then down a slight incline for a mile up a small grade hill and then flat for another 1/2 mile or so. All of this a four lane county road with office parks on either side. Then a goodly sized slope - picked up some decent speed - began thinking what would happen if I took a tumble - decided to stop thinking about it! One or two semi's and a couple of dump trucks added to the experience, but the shoulder at this point was wide and ample (but quite gravelly)
I had to cross over the two lanes for my left hand turn lane, but between my pretty constant mirror checking and a look back or two allowed me to gage the correct time. Last 1/2 mile was another slight uphill rise before my office complex. I was the only bike in a very old and decrepit bike rack although I have seen one other bike at times - company has >4,000 people at this site.
The return commute was not as bad as I was worried about. The long hill, that was so nice going down, was a challenge. My bike has a compact crank and is a nine speed so "only" 18 gears - I was worried that the low gear would not be "low" enough but my legs and it, proved equal to the task. Although I'd worry about any steeper grade hills (of which there are plenty of around here - SE Pennsylvania). The double blind ess curve was OK since I had a good rate of speed and I checked my mirror to see if I had "enough" clearance between me any any car/truck behind me. Most of the return trip was uphill, but on the spots that were not or flat, I felt I was more confident and ergo faster that the morning trip.
Weather is iffy tomorrow, but I'll give it a go anyway.
As for clothes, I wore regular jeans, t-shirt and light oxford going in and changed to yoga shorts and another t-shirt for the return trip. Regular New Balance sneakers on dual sided clipless pedals - I will seriously consider "real" bike shoes and some form of clipless (new pedals if required) as well as some other bike friendly clothes. We have a full blown locker room at work, showers etc... so I have good options
Final word? I think I can do this, unlike some on this forum with long commutes, mine is an easily managed 4+ miles