Boston is a town full of people on bikes which should be a good thing, but some of the things you see people riding make me cringe. I am not talking about dept store bikes or budget bikes, but idiots who think just becuase it's a "fixed gear" all other rules of bike fit and gearing go out the window. This is a short list of some of my favorite malfunctions.
1. Bike fit. Small person giant bike is always a good one (just like Chris Farley in the tiny jacket-it is funny but doesn't look right or work well), but the too tall seat post is another classic. Are you trying to look like Pettachi? If you look like a hunchback bending down trying to grab you bars, there is a thing called an allen wrench that can help. Couple the huge drop and reach with a giant messenger bag and an average speed of 10MPH and you have something that looks like a grazing camel not a bike rider.
2.Gearing. Are you trying to win the kilo? What is up with the giant gearing? Do you want knees when you are 30?. Too hard to spin and too hard to stop. Why is there a 50+ tooth ring on your bike? Why is their an 11 or 12 tooth cog? 60-70RPM worked for Ullrich but one of his thighs was the size of your waist. Learn to spin. Ask someone about gearing. Riding a bike can be fun and fast.
3. Helmets. I hate to be the scold on this one and I am a hypocrite because I used to never wear helmets, but if you are going to play in traffic all day and do it half in the bag at night a helmet isn't a bad idea. A side note, kids rocking Cinelli caps when they are running no Cinelli parts (or Campy, etc) always annoy me, but to reiterate I am a hairy old grump so deal.