The photoelectron spectra of 3-endo-(2), of 3-exo-methoxybicyclo[2.2.1]heptan-2-one (3) and of 2-endo,3-endo-dimethoxybicyclo[2.2.1]heptane (4) are analyzed in comparison with data reported for other analogous systems and with predictions based on quantum mechanical calculations. In 2, the ''homo-gauche'' conformer (2G) is more stable than the ''homo-anti'' conformer (2A) whereas in 3, the ''homo-anti'' conformer (3A) is slightly more stable than the corresponding ''homo-gauche'' rotamer (3G)