Bikes have always specified the clamps by the frame size and there are lots of sizes. luckily unicycles have considerably fewer. The seatpost clamp is alway related to the frame outer dimension, not the seatpost. Although there are some simple rules with unicycles.
- 22.0 seatpost = 25.4 seatpost clamp
- 25.4 seatpost = 28.6 seatpost clamp
Aluminium frames are difficult to work out as they can vary a lot. So always check the product description before buying. Here is a quick list that may help:
- Cheap Chinese unicycles with steel frames and 22.0 seatposts = 25.4 clamps.
- UDC, Nimbus and Qu-Ax with steel frames = 25.4 seatposts with 28.6 clamps.
- Pre 2015 Eclispe and Equinox (aluminium frames) = 25.4 seatpost with 30.5 clamps.
- Oracle and QX with aluminium frames = 25.4 seatpost with 31.8 clamps.
- KH and Impact (aluminium frames) = 27.2 seastpost with 31.8 clamps.
- Eclipse and Equinox = 30.5, 31.8 or 34.9
- Qu-Ax RGB = 34.9