This hub and front sprocket assembly is used on the Chinese 98cc engines, specifically the Coleman CK100 and the HS100GK go-kart. May be used on other applications as well. This sprocket has 24T and is compatible with the 420 chain ONLY.
Sprocket details:
Small front sprocket with hub on the CK100
#420 chain
24 Teeth
ID 15mm (.58″)
OD 77mm (3.03″)
Chain Wheel II
(4) 6MM bolt holes
34.7mm (1.36″) bolt circle
Uses (2) 6002RS bearings
Be sure to measure your chain or current sprocket before ordering. 420 chain has 1/2″ pitch and 5/16″ roller diameter. Most Chinese sprockets have the chain size and teeth count stamped into the metal.