The Mountain Bike Life
Winter is coming and I was looking at my poor Talera still filthy from last winter and was thinking about changes I was going to make for this year. The biggest change I decided was to go to a single speed setup. Last winter I had problems with shifting in the cold and when the derailleur got packed up with dirt and ice. So the solution this year I am going to pick one gear and go with it. Also I decided to ditch the front suspension, but that is another conversation altogether. This is not my first single speed conversion, so it didn’t take me long to figure out what to do, but there are a lot of things to consider. To get started read my previous post DIY Single Gear Crank Conversion to know what to do up front. You don’t need the chain guide, but you do have to convert you crankset to a single gear setup.

Origin 8 single cog spacer kit.

Next we need to look at the frame of the bike and make some decisions there. The main ingredient to a single speed bike is only having one gear in front and in back, negating the need for a derailleur. So how to do we keep the chain taunt? The easy way is if your frame supports single speed setups or not. Look at your rear dropouts and see if you have vertical, horizontal or an angled slot back there. If it is horizontal going straight back the frame was primarily intended for a single speed cog. Easy case closed. The angled dropouts are not really meant for single speed setups, but they will work. You just have to make sure you get your axle good and tight so it doesn’t slip. Last frame type is the vertical dropouts meant for true quick release rear wheels. Through axles also fall into this category. There is no way to adjust the axle back for tension on the chain. So we have to put a tensioner on the bike in place of the derailleur. Not a big deal, but just not as pretty.

Make sure your chain is straight from cog to crank.

If you are in the same boat as me and you want to keep costs down by reusing as much existing as possible. You can certainly purchase a single gear rear hub/wheel, but odds are you are just going to remove your cassette and put on one fixed gear. Easiest way to do this is to buy a spacer kit and single cog. These come as a kit and if you also need the tensioner you can get that at the same

time. Just the spacers are about $15, $10 for the cog and then another $20 for the tensioner. Some kits even come with multiple cogs for different gear ratios. Since I had done this before and had a cog laying around, I just needed a spacer kit. Newer spacer kits are now a bit nicer with more cog support. If you have the cassette removal tool laying around pull off your cassette and then put on your cog, but don’t tighten it up just yet. With your single gear crank on up front lay a chain across your crank gear and rear cog and make sure it is a straight line front to back. Adjust the cog in or out with the spacers in the kit as needed. If you are having a bike shop perform the work bring them in all parts, not just the rear wheel as they will need to center the rear cog.

Newer spacer kits support the cog better side to side.


Gear ratios are something to consider here as well. Typical setups are 32 up front with 16/18 out back. That is a good middle of the road ratio. I had a 34 gear for the front and a 20 tooth for the rear so it will be about the same. I may drop down to an 18 in the back after my first snow ride. Either way this may take some experimentation

to figure out what is the best ratio so be prepared to purchase a couple for rear cogs. Fortunately they are cheap and easy to swap out if you have a cassette tool. Did I mention you probably should buy a cassette tool kit? They come in handy when you have a bike obsession.

Horizontal angled dropouts can be used for single speed.

Now that you have all the parts together you need to put on your chain. If you have a frame where you can tension with the dropouts put the wheel all the way in and then shorten the chain to as short as it will go, but still able to be connected with a little slack. Once your chain is fastened slide your rear wheel back and tighten the axle. Just make sure the axle is straight in the frame. Also you don’t need the chain to be super tight. About ¼ inch deflection up and down is fine. if you need to use a tensioner put that on before you thread the chain. They usually bolt right where your rear derailleur went. Some have a spring to pre-tension and some require you to manually set their position and lock them in place. Either way put your chain on and get it as tight as you can with the tensioner in place loose and then take up the slack with the tensioner. Single speed chains here are not a requirement, but I highly suggest them since they are designed not to walk off gears. Compared to a 10 speed chain they are a pretty cheap investment too.

This dropout (track forkend) is meant for single speed setups.


With it all together take it for a ride. You may find you need to retension the chain or shift the sprocket in the back in or out if it the chain slips off. That should be it, just set it and forget it. There are no gears to slip, cables to get loose, derailleurs to align or chains to set. I find it simplifies your ride a little bit. Sure hills will be a bit tougher to get up and you won’t be able to go as fast down hills………but this is about enjoying the ride not going faster. So do that!

Lest We Forget
Unfinished Business

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