Cog sizes are measured by how many teeth they have: obviously the bigger it is the more teeth. And the bigger it is the easier it is to ride (but the quicker you have to pedal to gain speed, like when you are on a easy gear on a geared bike).
I have a 42t chain ring which means in combination with a 17t cog the gear inches are just below 70; in other words , a relatively easier gear than my singlespeed set up of 42-16t, less knee pains and hopefully more chances of controlling the beast with my weak legs! Here is a handy fixed gear cycling calculator in case you want to calculate your fixie / single speed set up...
...and below my cheesy video installing the fixie cog!
PARTS NEEDED:
- 17t cog (i chose the Halo one)
- a lockring to secure a track cog on a track hub.
- fixed hub (already on my wheel)
TOOLS NEEDED:
- Combined Chain Whip and Lockring Tool (bought from VeloSolo) to tighten the cog and lockring
- wrench (to take off the wheel)
