i was cruising fullerton loop awhile back and came across the elusive mr. jackson and as i was talking with him i aired down my tires. well being not to knowledgeble about sum things i let what seemed to be too much air out of the back tire. so as we moved along the rear tire was too soft ,i asked mr. jackson what happened,? he told me that back in the days of the old bike i was riding the tire co's. made a two stage valve stem,i thot no way it didnt happen to the front,he told me i had one in the back tire only.boy did i feel dum. so it lets more air out than a single stage valve.strange never herd of that has anayone else? :?:
