Here’s what Peter offered for anyone wondering. Presumable 28.6 is top tube diameter and 31.8 is down tube/sea tube?
The 28.6 will be the seattube, 28.6 - 0.8 x2 = 27.0 seatpost or ream it out a bit for 27.2mm.
@M_V started
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
Here’s what Peter offered for anyone wondering. Presumable 28.6 is top tube diameter and 31.8 is down tube/sea tube?