1000Calories

I have an old road bike that I fixed up. Replaced a bunch of parts on it. It used to be a 12 speed, but since I only cruise around the park I decided to leave it on one speed. I had bought a new crankset. It's 44T, lowest cog gear is 14T. The ratio is close to being perfect. I want it a little easier on the knees and easy to pedal. Since I'm not changing the wheels until next year, I'm leaving the freewheel the way it is. Im just going with changing the crank to maybe a 39T. Not sure if this will make it too easy?

dylandewandel

I'm looking to setup a fixie myself, I know this guy just broke 10,000km of his 16,000km trip around Australia on a 48/16 setup. It honestly depends on your elevation fluctuations and fitness level; I'd be far less worried about it being too easy than too hard, higher cadence isn't usually a bad thing. Try the 39T, find out!

Colnago Mixte

I knew nothing about fixed gear bikes until about 6 months ago, when I bought a used one, so I may not be the best source. Mine came with a 42x16, which I laughed at when I first saw, thinking something like 53x16 might be more appropriate.

Was I ever wrong. 42x16 is plenty, once you work on your spin and figure out how to go fast in a gear like that. Where I ride the bike is dead flat too, the wind is the only thing I need to worry about. And I'll tell you, fighting a 15-20 mph headwind in a 42x16 fixed gear will definitely tire you out. And if your knees flare up, too bad, you gotta keep pedaling.

What I'm most amazed at is how is easy it is to vary your speed so much, with just one gear. And how tiring it is to sprint, but not be able to coast afterward. Also the danger, I still catch myself trying to coast, and having my leg jerked back into motion. Especially when something happens quickly and I react purely on instinct. Old habits die hard, so watch out for that.

TimothyH

The only way to know what gear will work for sure is try it.

48x16 is probably a little high for most people just riding around. If you are an aggressive rider willing to work or pretty strong already then it is probably a good gear.

44x14 is about 83 gear inches. This is a pretty high gear for most people on the road, especially with hills. .
39x14 is about 73 gear inches, about 13% lower.

48x16 is about 79 gear inches. This is what I run but again, what works for me is not necessarily good for anyone else.

It is probably good to start around 70 gear inches and see how it feels.

BikeCalc.com - Bicycle Gear Inches Chart

1000Calories

Thanks for the feedback guys. I forgot to mention that I don't ride a fixie. My main goal is to just coast easily without it being to stressful on the knees. Current ratio is eh, doable but needs to be less.

europa

The gearing is irrelevant to whether it's fixed or not.
The ability to coast is over rated, massively over rated - where you may coast on a bike with a freewheel, it's easy to just let your legs roll over and it's better for them (keeps the blood flowing to flush out the lactic acid)
I ride 66 gear inches after finding that 70 felt a little high at times. On the other hand, I'm a spinner when I a geared bike too.
For the record, my average speeds and max speed are the same over the same route whether I'm on my fixed gear or my geared bike.

Gearing. It's a simple matter of making a guess, trying it and modifying to suit.

caloso

HTupolev

"Flushing out the lactic acid" isn't a real thing. And while keeping the legs turning over often feels better than coasting, this is more true when you've got a gigantic ratio to slow-pedal in than when you're doing 150rpm downhill at 30mph in a 66" fixed gear.

There's also the matter of cornering...

europa

I may have been wrong in using the term 'lactic acid' but you're wrong in claiming it doesn't flush out the crap in your system. It also applies no matter what gear you're using and regardless of whether you're riding fixed or geared. This is something I've checked with someone who knows. Believe what you want.

As for cornering, that's no issue at all unless you've converted a geared bike with a rather low bottom bracket. Although I've touched a pedal with geared bike conversions, it's only ever been at low speeds and I've never touched a pedal on a bike designed for fixed gear. Pedal strike is more a product of poor technique than a real fear.

HTupolev

The things that need to get flushed out of your system don't require a high spin to do so. And the added load of doing a high spin when it's unnecessary holds back short-term recovery, and can even cause fatigue in and of itself.

Viich

Back to the OP - 44:16 is very common in off-the-shelf single speed / fixie. I rode this for a while, liked it fine. Sheldon Brown likes using a 17T rear cog if you ride fixie and skid brake - not a concern for you. It doesn't matter that much - anything is going to be a compromise in going with a single gearing. If I were to build one right now, I'd probably go 48:17. Choose something low enough so that you can get up the biggest hill you need to.

1000Calories

I believe the second cog gear on the freewheel may just be a 16T. I could place the chain onto it and it hopefully won't slide off since there is no derailleur on it. Either way I have to get a new crankset because the cheap one I got I had an issue with. So that's why I'm deciding on what T count I should go with. I have a Shimano UN 26 bracket square taper and the left crank arm didn't fit on all the way but still bolted it down. Now the arm is wobbling and my fat ass must have grinded down the metal. Haha! Newbie mistake. It's my first road bike. Didn't have a big budget to get another crank but this time is mandatory. On topic, would the 44/16 make it easier than 44/14?
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fietsbob

44>43>42> 41>40... or 14>15>16 ..

Reynolds 

42x16 or 42x15 for me.

Oldguyonoldbike

big chainring 

When talking gearing I like to bring up Ray Booty..."the boot". English time trialer who in 1956 was the first to break 4 hrs in the 100 mile TT. 3:58 and 20 some seconds. His gear of choice and pretty standard at the time...84" fixed.

It was customary back in the day to start the racing season on a 63-68" fixed gear for the first few hundred miles.

70" gear is plenty for an easy going around town gear.

1000Calories

83 gear inches huh? Well I did look at a chart yesterday, I was figuring what lower number I should go into. I'll try the 70. Thank you! Some charts are different with the measurement.

Edit: What do the color groups represent? Does green represent higher/tougher ratio group and blue being moderate/easier group?
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