First of all, do not listen to the naysayers, and go the build-yourself route. You'll be glad you did.

That said, there are several options on how to do that, and they differ in the amount of money and work invested, as well as niceness of end result.

The cheapest alternative is to get a beater geared bike with horizontal dropouts. Always look for horizontal dropouts, in used bikes or frames. So, old geared bikes can be had for peanuts. Then what you can do is just remove the derailers (front and rear), remove the shifters and remove some segment of the chain, in order to have it tight. The horizontal dropouts will enable you to tighten the chain by pulling the rear wheel back as much as needed.

Then what you could do, to make things even tidier, is to remove the unnecessary chainrings and cogs (you can find spacers for cassette hubs that convert it into singlespeed setups, such as this).

Obvious further steps would be to buy a new crankset.

An example of bike/frame I'm talking about, is this.

A frame you do not want, is for example, this, because it doesn't have horizontal dropouts.

Alternatively, and a step up in total expenses, you could buy just a used frame (but a nice one), such as this. Of course, you must keep an eye on eBay to run into such nice frames at a low price.

And then the more expensive alternative would then be to get a brand new frame.


Do not forget that the frame size is extremely important, and has to match your height, your inseem etc. Generally, the taller you are the bigger frame you need.