Yep, especially around here on Altadena/Glendale/Pasadena dirt!

Gearing in low 50s (gear inches) is probably about right for single track riding. At some point I want to give my RockHopper the option to run two chainrings and two rear cogs with a general gearing around 65 and single track gearing around 50. Like 42/17 and 39/20.

Otto

I've done mid 40s or faster in a 42x17 many times. (As a 20 something ex-racer with "issues", I used to ride up Oakland's Juaguin (sp) Miller to Skyline Blvd, turn around and ride down. 4 lanes separated by a park-like median. California. I never got passed.)

Years later and much older, I've had cars pull alongside and tell me I'm going 35. On easy descents in Portland. I still go much faster coming down from the Portland west hills. My commuter is geared a little higher. 44x17. My racing spin is 40 years gone.

Way over 200 RPM is easy with training, lots of fix gear riding, plenty of high speed descents around and really good foot retention.

I use toeclips, quality leather toestraps and slotted aluminum cleats in good condition. Toeclips because if I do pull a cleat out at 40MPH plus, my foot is still in the straps and with the pedal. It's a heart-stopping moment, not a life-changing injury and crash. The pedal striking the Achilles is going to be more severe than the following crash. I don't do these fast descents much now but I am 68 years old. The cleats - Exustat track cleats; the ~$25 ones. Take any 3-bolt shoe. As good as (or better than) the best of the pre-clipless days. Don't use pedals with aluminum rattraps. The aluminum cleats will eat them.

I only mean its "crazy low" for riding in fast drop rides, for mountains the ratio is pretty darn heavy

Hey, I live in Echo Park. I need to run 42/18.

My bargain basement Thruster Fixie, I ride as a single speed, came with 48-18 sprockets. Seems pretty rideable to me, and a good compromise gearing. So, the gear ratio s 2.66. The bike runs 700C tires. Anyone else run this gearing?

Yes, I have a bike I sometimes ride with exactly that same gearing. Cyclists don't often use units like 2.66 gear ratio; we prefer to put it in terms of gear inches, which you can easily calculate H E R E. Your 48 x 18 gives 70 gear inches, a very good compromise for general fitness/fun riding on pavement anywhere the terrain isn't super hilly.

Yeah, that's about what I thought. Seems to work pretty well for me.