Replaced my 42t chain ring with a 45t Rocket Ring that I picked up from Sheldon. Kept the 16t cog on the back. Even though this change adds only about 5 gear inches (75.9 up from 70.9--w/ 170 cranks and 27in. wheels), the difference on the road is phenomenal. My biggest concerns about going bigger were being able to get a jump on traffic from a standstill, and the two moderate hills I encounter on my ride home from work. So far, no worries on both fronts...and the ability to build speed, without spinning like a phreak, just rules. I was twenty minutes late to work this morning, because I couldn't bring myself to ride my desk all day before doing some time trial work down M street. What a great way to start the day.

I have been going the other way with my chain rings. I started with 42/14 or 81 Gear Inches and rode that way for a few years. Now I find that I am going to a lower gear inch number. Currently most bikes are various combinations of 70, 71 and 72 with one used for trail work at 68/63 flip flop.
I think if you have relatively flat terrain you can get away with higher gear inches and I started to ride lower when I took off all the brakes and that helped me stop better. I ride the hills a lot here in Ohio. Yes, there are hills here that are short, but steep. Older knees may be an issue at 62 years of age.
Who cares what is correct, as long as you can ride.

fixedgearhead

Are you sure that isn't the EPO talking?

screaming, my friend, it's screaming...

I've got blood like molasses.

m street is one bad ass street!

iv been trying to get a job as a courier, and have been riding around dc lately on a fix, and m street and georgetown in general is one area im not too fond of. too many potholes, road construction, and brick laid streets. i hate that area.

iv been riding fix for the last 3 months or so, and its really brought me into biking, and made it something i really embrace.

sounds like a good thing Schiek. I try and ride around that ratio as I prefer the power on the lakefront path here, yet can't go too steep for the streets.