there are actually 2 different bikes pictured.One is modern firmstrong chief,other is 1954 Schwinn "Elgin".Both have ZA50 "puch"motors.Completely rebuilt,casematched to 70cc reed kits.20mm mikuni carbs and custom intakes and k&m breathers."elgin" has puch boss pipe and chief has Homoet 4p pipe.gearing 20X36 on chief and 19X35 on elgin.Yes they are a blast to ride.scream off the line and topend is scary fast.