4500 is a wad of disposable sports outflow

interesting finding a revolution happening

https://www.google.com/search?ei=QCI....B9E Qn_J1FJ4

https://www.google.com/search?ei=GiI....0.DoU70om_8v8

what manufacturers are mounting Gates ?

a toothbrush n soap, gears last forever like the Rollout/Shimano rear gearbox