NBT2: removing the cassette lockring

The Next Best Thing mk2 removes cassettes on the road without extra tools, eg to replace a broken spoke. The NBT2 is designed to fit Shimano compatible lockrings (not Capreo). 8 speed Campagnolo lockrings are slightly different, but for occasional use the NBT should work just fine. The NBT cannot be used with  conventional freewheelhubs. And the NBT2 shouldn't be used with extremely lightweight aluminium (Stupid-lite[tm]) racingframes: these have enough problems of their own.

Prior to first time use it is recommended to check with conventional tools that the lockring hasn't been tightened way over the recommended torque by some hamfisted mechanic.

Instructions (download the printversion)
  • Open the rearbrake.
  • Engage first gear, eg engage the largest cog and smallest chainring. put the cranks horizontal.
  • Release the QR skewer, and remove the endnut and conical spring.
  • Fit the NBT2 in the lockring and put the axle back in the dropouts.
  • Replace the skewernut (no need for the spring) and do up the QR tight
  • Ensure that the axle is fully home.
  • Grab the cranks with both hands, and unscrew the lockring one turn. If the bike is standing on it's wheels, it will want to ride forward. 
  • The face of the lockring is serrated, a load ratcheting sound is normal.
  • Remove the wheel from the bike and remove the lockring by hand.
  • Fitting

  • Take care when replacing the cogset that all cogs are fitted with the wide spline engaging the corresponding groove in the freehubbody. It is very easy to disturb the position of the endcog when tightening the lockring, and this could seriously damage the freehub. With the lockring handtight, the cogs shouldn't wobble when spinning the freehub.
  • To properly tighten the lockring, put the wheel back into the frame. Gently (the wheel is a large lever) rotate the wheel backwards to tighten the lockring. If you start with the lockring handtight, 10' (45º-60º) is sufficient.
  • Remove the NBT2, and replace the QR (the smallest diameter of the conical spring goes against the axle). 
  • Check the rear brake.