Only after the war could Moeskops turn professional. In 1925, in Amsterdam, he was beaten in the semi-finals. In 1929 and 1930 he reached the finals but was defeated by the Frenchman Lucien Michard.
Moeskops was a good tactician, studying opponents carefully so that he could predict where someone would attack him.
Foreign a cyclist he was very tall and was known as "Big Pete". In 1930 Moeskops underwent major surgery which accelerated the end of his cycling career.
His last major victory was in the Grand Prix of Alis (France) in 1933. In retirement he became the owner of a café.
He was a national hero, and in 1963 he appeared on the television programme Voor de vuist weg with Willem Duys.
A year later he died in The Hague, at 71 years of age. Moeskops is buried at the "Old Oak" cemetery in the Den Haag Dunes. The municipalities of Krugersdorp and Nijmegen, and the Loosduinen district of The Hague, have streets named after him.