Academy entrant bmx bikethe academy entrant is an ideal entry level bmx bike for shorter riders due to its extra short 19 5 top tube this bike is extremely responsive and agile which makes it more manageable for younger and shorter riders the hi ten steel frame can take plenty of abuse and the sealed bb and rear hub are extremely durable features frameacademy entrant hi ten 19 5 tt 13 25 cs 75 0 ha 71 st usa bb external headset forksacademy entrant hi ten tapered legs handleb