I wanted to report back that today is my 1 year commuting anniversary. I’m up to 4 days a week, 26 miles round trip and my current gearing is 44×16 on MTB cranks. I’ve tried several ratios over they year and found that anything taller slows my cadence too much, so the 44×16 seems to be the ticket.

By the way, I commuted over 2500 miles last year and I’m pretty proud of that..

Thanks for all your help.
AC

I actually rode to work today for the first time ( yay! ) and decided to go with the 39×18, which worked out nicely. I changed my route slightly and I have several overpasses which required out-of-the-saddle climbing with the 39×18, so I would have been sucking big time with the 53×18.

Thanks!
AC

Because cranks turn with the wheel on a fixed gear, the bike’s momentum is always driving the cranks — thus, unlike on any freewheel set-up, momentum is helping you pedal. This can be a disadvantage on downhills, but on climbs, the fact that you’re moving actually helps you keep moving, if you see what I mean.

If you go to Sheldon’s gear calculator, he also has a choice that will give you rpm at any given mph. What this indicates is that in YxZ gear, A rpm = B mph. Ultimately, on a fixie, maintaining A rpm is easier once you are up to speed, because a certain amount of the force required to turn the cranks is being provided by the bike and your own mass.

My only thought in raising that earlier was that I don’t know whether a YxZ gear on a fixed gear would feel the same on a SS, or whether you’d want something smaller on the SS. Then again, AC’s ride is relatively flat, so it won’t be much of an issue.

AC:

Regarding chainline — if you were just changing the gearing on an existing SS set-up with a good chainline, what happened? Nothing that I know of about changing the size of your chainring should have changed your chainline. I suspect you may find that switching cranksets will create more problems than it solves — or, rather, if your chainline improves with the 105 set-up, it will just be luck that it lines up better with your rear hub.

Thanks again..
AC

I tired to mount a 44T to my current MTB cranks and the chain line was off by a mile. I thought about mounting the chainring inboard but my cranks don’t have the inside lip to hold the chainring in position, so I nixed that idea I went a head an ordered the 105, which should be in today. I cannot wait to get going..