Reply To: Rear sprocket Aug 10, 2021 at 12:31 AM #6095 ♠️ M77👑 Admin Topics: 40Replies: 3,018Country: UKBike Model: GT Front Sprocket Nut = M27 SOCKET Rear Sprocket Bolts = M8 x 40mm (ish) and Nylock M8 Nuts. Use stainless.