... brake we normally send you with drum, if you need a disc brake, please advise us before shipment.Product Information e ... so if you need size 2.5, please specify it to us; For 20", 24", the tire size is 1. ... 125, if you need size 2.125, please specify it to us; For 28" wheel, the tire size is 1. ... kit because of the problem that you don't know how to install it does not fit your e-bike.Motor Performance ...