Choosing a Singlespeed Ratio

All first-time singlespeeders wonder what gear ratio to start out with. How big or small should the chainring and rear cog be? Can existing chainrings or gears be reused? What's best for a beginner?

It's often said that for mountainbikers, 2:1 is the best to start. This means that if your front chainring is 32 your rear should be 16. So for every revolution of your pedals, the rear wheel makes two. By the way, a 34:17 ratio is still 2:1.

For road riding the ratio needs to be much more aggressive - a bigger chainring and a smaller cog for faster road speeds.

Back to mountianbiking - while 2:1 may be a good rule of thumb, there are a number of factors you need to consider:

How strong are you?
If you're the fastest and fittest rider around, you may do well with something more challenging than 32:16 - you may try 32:15*...but that's highly dependent on the next point.

How hilly or flat are your trails?
If you live in the Himalayas or Tetons 32:16 may be crazy hard, meaning you won't be able to climb many hills no matter how fit you are. But if you live in Kansas you may want to look up some roadie ratios!

How much road riding will you do?
I have to do a few kilometers of riding to get to my trails, and anything beyond 32:18 makes me spin out really fast on the road - pedaling like crazy but getting nowhere fast.

How much pain are you willing to endure?
If you think you can train up fast, 32:15* could be good - but be ready to suffer. I started on 32:18 but then moved to 32:16 and never looked back.

What components are you using?
Are you on a 26" bike or 29er? This changes the ratio. How long are your cranks? 175 or other? This will affect your ratio too. Check out Sheldon Brown's online gear calculator to get into the dirty math.

Also, if you can manage to find the 'magic gear' or the ratio that gives you a tight chain based on your chainstay length, meaning you won't need a tensioner, you may be inclined to go with that. But will that ratio be ideal for you? This could dictate your ratio. See the Fixed Innovations magic gear calculator.

If you opt for a cog less than 16T, you will have fewer teeth interacting with the chain (less chainwrap) which can lead to chain skipping. Even with a 16, you only have 8 teeth biting into the chain, and on a tough climb you could blast your chain over the cog.

In short, the more teeth on your cog (for mountainbiking) the better. But your 30 speed bike has an 11T cog you say? That's because gearies will only use the 11T on the fast flats or downhills - when they hit a hill they always shift to an easier gear!! ALWAYS!

Plus, because you are never shifting gears, that rear cog is constantly subjected to wear, and the smaller it is, the fewer teeth there are to absorb all this brutal chain pulling. Smaller cogs wear out faster.

The workaround, if you need a 15 or smaller in back, is simply to get a larger front chainring. 32:16 is the same as 38:19, for example, except with the 38:19 you have a lot more chainwrap. Less skipping, less wear.

A new Surly 16T cog

Once you have considered these factors and understand the variables, simply ask other singlespeeders in your area. Another approach is to ride a multi-geared bike in a certain gear for a while and don't shift. It will be hard to resist the urge to shift but this is a good way to find out what you are capable of.

You will be surprised.

*The 15T idea is just for illustration purposes - it's not recommended to use such a small cog - see the last section on components

Why Singlespeed?

This is the question that those that have never ridden singlespeed ask, and with good reason. Who would really want to reduce pedaling efficiency in a sport that all to often tries to optimize it?

Who, masochists aside, would voluntarily - happily! - subject their bodies and minds to such a Sisyphean task as climbing a hill in the 'wrong' gear?

Some singlespeeders say they can't explain it.
Some say it's almost spiritual.
Others say it's just 'better'.
Many prefer the simplicity, lack of derailleur clicking and clanking, and the fact that it's quiet.
Almost all agree that it's more just more fun.

But so far, none of these answers really addresses the question very well. So let me give it a try.

First, however, I want to clear up the difference between fixie and singlespeed, for the non-bike geeks out there.

And all too often singlespeeds are confused with fixed-gears, or 'fixies'. Which is a big mistake - fixies are often ridden by urban hipsters, a far cry from the mountain biking singlespeeders, who actually wear helmets and don't care about style like they do performance.

You will not see Hipster on a trail.

A fixed gear bike has a direct drive from the chain to the wheel. The hub does not allow for coasting - the cranks and pedals are always turning (as long as the rear wheel is moving). To brake, they push on the pedals backwards - they do not generally have brakes.

The only real similarity between fixed and singlespeed is that neither has any derailleurs or can change gears. But that's where the similarities end.

On mtbr.com, sparty attempts to explain:

The "Why singlespeed?" thread is coming up on a year old now. There are over 200 replies in that thread and none of 'em belong to me. Over the years I've spoken up about what I think makes singlespeeding great but the very title of that thread made me feel like it was going to be a debate, and I get into way too many debates without doing so intentionally. So I purposefully avoided that thread until today. But today, reading it made me reflect on why I ride a singlespeed. 

So I've written a little story about some people you know. It's a story about how a few local (Eugene, Oregon) guys came to love singlespeeding so much that now maybe half the riders in our club, The Disciples of Dirt, ride 'em. And we're a pretty active club.

Because of the nature of historical perspectives, I'm sure this story is littered with inaccuracies.So be it. The characters with diverse and equally innaccurate perceptions will no doubt be along soon to fine tune the white lies. 

Anyway, let me begin... 

I'd been mountain biking less than a year when I met shiggy in late 1985 or early '86. Back then he went by a different handle, which shall remain deeply imbedded in ancient history -- "shiggy" is bad enough. Anyway, shiggy and a guy named Justin and I (you've seen photos on this board of Justin in pantyhose and a thong at Barbie Camp) used to ride off-road quite a bit together back in the late '80s.

We rode geared bikes back in those days. But shiggy regaled us with tall tales of a singlespeeder he'd ridden with years earlier from the coast; this guy rode a custom IRD singlespeed with platform pedals, 206mm Bullseye cranks and a pretty big gear (especially considering the rugged hills of Oregon), even taller than 2-to-1. And this guy was over 50 years old. Whoa! Needless to say, young-at-the-time shiggy was mighty impressed.

Pesonally, I just thought the guy sounded crazy. Justin was too busy riding his bike underwater in Oregon's winter puddles to care.

We pushed the idea of singlespeeding onto the back burner but shiggy clung to the legendary memories about the guy on the big bike with one gear.

Fast forward about eight or ten years to the early '90s. Josh Ogle (yeah, that Josh Ogle, of Jerichofame) was renting a dark, dank run-down dwelling not far from downtown Eugene. Josh occaasionally joined the Disciples of Dirt for our weekly night rides in the Coburg Hills north of town. One night he showed up on a homemade singlespeed (er, make that a "custom frame").
Eyes rolled.

We laughed at him. Yeah, we laughed at Josh Ogle for bringing a singlespeed to an off-road ride.
Well, shiggy didn't laugh. His inspiration had been burning inside him for years. A debate ensued.

After that, shiggy started riding singlespeed off-road. 

"What?" I thought.

Next General Coonskins took it up. I thought this was a real joke, because here was a guy who Icould beat going either uphill or downhill, and now he was going to make his life worse by limitinghimself to one gear. "He'll hate it and pitch that stupid bike off a cliff soon enough," I thought tomyself.

But that's not what happened. Late that summer, on one of the hardest group rides that our club does every year, Coonskins freakin' rode away from me like I was standing still. The only time I saw him all day was when he'd wait for us gearies to regroup. This ride has HILLS, folks. Big ones, steepones, long ones. I was stunned by 'Skins transformation.

How could this happen? My reality was becoming distorted. I did not understand. Coonskins went on to race the Cascade Creampuff. To say he'd earned new respect is an understatement. Currently, if he's not the strongest rider I know, I don't know who is.

I decided I had to get a piece of this singlespeed action for myself. I wanted to become a strong rider, too. I wanted to keep up with my friends, no matter how little sense riding a singlespeed seemed to make.

Honestly, I never expected to like it. I just wanted to get strong.

And I did. Get strong, I mean. That was six years ago. But I found that once I got strong, I liked singlespeeding, too. What's funny is I can't say exactly why I like it so much. I just do. In fact, I like it better than any other kind of bike riding. It's so rewarding. My mega-bling FS bike doesn't see much action these days.

And that's why I ride singlespeed.

Personally, now I think the title of that other thread should be, "Why not singlespeed?" Just askshiggy, or Josh, or General Coonskins -- they'll tell ya.

So hopefully that clears it up a bit. I'm a new convert, but I'm here to stay.

Post taken from MTBR.

Teaching a Kid to Ride a Bike

I only started riding just before my son was born in February 2008. But when he was born I knew he'd be on a bike soon, judging by how much I loved it. There was no way I couldn't teach him to ride as early as possible.

When I was five, my mom threw my on my older brother's 20" dirt bike and pushed me down a hill. I remember it clearly. I learned pretty quickly, without any training wheels, but the way my well-meaning mom taught me scared the hell out of me.

So after my son was born I started looking for a bike he could easily learn on. I found the KaZAM at a local bike shop. It's a bike that doesn't have any pedals, so the child can focus on balance and steering.

I could really appreciate this bike - it had real wheels with spokes, nipples, tubes, tires (12"); a quick-release seat clamp, proper bars, and grips. 

The KaZAM.

I bought it right away and took it home. At 26 months my son could just barely touch the ground while sitting on it (with the saddle all the way down).

A few rides and he was propelling him self along, oblivious that between his strides he was actually balancing. He could ride.

Check out the technical skills he learned at 28 months in the video below. These will come in handy on the trail soon.

How to do a Singlespeed Conversion

For about a year I've been wondering what the attraction to singlespeed was. Why would anybody want to remove their gears and have to resign to one ratio that probably wouldn't ever be optimum? What's the appeal in being neither ever able to go up hills or fast on the flats?

Well after reading a few forum posts in mtbr.com and some content from Sheldon Brown, I could see the answers clearly:

1. Simplicity. There's a lot to be said for 'keeping it simple'. It's elegant, clean, and not much can go wrong.
2. Speed. Yep, speed. All the singlespeeders I ever rode with blasted past me. I could never catch them and I wanted to find out why.
3. And the most obvious one, weight.

 Conversion kit, including cog and lockring

So I took a trip to Fab's Cycle (Singapore) and picked up a singlespeed kit. This is simply some aluminum rings (in a variety of sizes), a lockring and a cog. The one I got was 18t.

You will probably also need a chain tensioner, as your rear derailleur will be removed, you'll need something to keep the chain taut and from falling off.

I couldn't find one when I did my conversion initially.

Step 1: Remove lockring
To do this you will need a chain whip and a cassette lockring tool, along with a wrench.

Goodbye cassette, we won't ever need you again.

It may be tight, but crank the wrench counterclockwise with your other hand on the chainwhip to prevent the cassette from spinning. The lockring will come off.

Step 2: Pull the cassette off
Now here's where I ran into my first problem: The cassette's cogs had dug into my soft aluminum freehub body, gouging itself in. I had to rally yank on the cassette to get it off.

Step 3: Put the spacers and cog on
Once the cog cassette is off, all you have to do is slip a few spacers on and then add the cog. But those grooves in the freehub body prevented me from sliding the cog on.

Cassette partly off.
Notice how the three biggest cogs are all connected. 

Cassette off.
Notice the grooves in the freehub body.

 

The cog wouldn't fit!

...and it slid right on.

A bit of filing...

Tightening the new lockring.

And the final result.

Somewhere along the way you have to remove your front and rear derailleurs, and maybe front chainrings (unless you're already on 1x9 or 10).

It's obvious from the image above that the chain is too loose. If you are lucky and your chainstay is just the right length, and you have chosen the right cog sizes, your chain may fit perfectly. But finding this 'magic gear' is hard.

There are a few solutions to this - get a tensioner, buy an eccentric bottom bracket, or get a frame with horizontal droupouts (ha!). I chose the first.

With the tensioner.