An angle could exist among the highest tube and the bottom but is generally parallel. Alternatively, some bikes don't have any top tube or possibly a vertical angle, producing receiving on and off simpler. A Schrader valve functions depending on a poppet system, when Presta valves operate with a smaller https://dirt-bike-engines80875.theideasblog.com/35593249/new-step-by-step-map-for-bike-parts-shop