Why does Jonathan mistrust the officer who wants to take his bicycle?

In the story, Jonathan mistrusts the officer because the officer seems insincere. To Jonathan, the insincerity of the officer is demonstrated through the lack of firmness in his handshake and the absence of conviction in his manner.
Because Jonathan suspects that the officer may have wished the bicycle for himself, he decides to bribe the man. After sizing up the officer, he offers him two pounds in exchange for retaining his bicycle. The officer agrees to the deal, and Jonathan rejoices that his prized mode of transportation is safe for the moment.
To ensure that his bicycle stays safe, he buries it in a clearing in the forest, where the dead of the camp and his youngest son are buried. After the war is over, Jonathan digs up his bicycle again and oils it. Then, he uses it as a taxi to ferry camp officials and their families to and fro along the path that leads to the nearest tarred road.