I have two bikes one has a Grubee engine and the other has a Dax engine. The gas cap on the Grubee vents like it should but the cap from the Dax engine does not vent right. When i look at the two i can not see any difference betwen the two. Has anyone had a venting problem and fixed it or found out what is the cause of the cap not venting? I know that i could just buy a new one but i like to know why some thing does not work.