Our #420 chain 25 tooth rear sprocket for Coleman KT196 and CK196 196cc 6.5 Hp go-karts is a 4.16" disc with a 1.73" center hole. The four mounting holes are spaced at 2.63" across from each other.

Specifications
Chain size: #420
Tooth count: 25T
Outside diameter: 4.16" (106 mm)
Center hole diameter:1.73" (440 mm)
Mounting holes: 4
Mounting hole distance across: 2.63" (67 mm)