50cc to 125cc: Ideal for newbies and urban commuting, offering great gas efficiency and simplicity of dealing with. A Schrader valve functions determined by a poppet mechanism, although Presta valves do the job with a smaller diameter on bikes with thinner rims. The head tube with the fork is definitely https://bikeenginesexplained62713.bloggerbags.com/40369130/bike-engine-types-can-be-fun-for-anyone