Hello Hope everyone is doing well.Need some help not Sure if I need to go to mechanic section or just stay in classic,Aways,1980 Faggin replaced 5sp freewheel 13t-26t to a 5sp 14t-28t rear derailleur is Campagnolo N/R.Won”t shift to 28t gear I changed gearing for Eroica.Thank you for your time and help.Be Save Peddle On