not 100% sure but i think 81 use plastic, or at least the front fender was made by M.Robert, italy. thats what Les from vintage plastics told me, i dont know if its right though. i do know that 82 onwards used Acerbis and ive got a NOS front red one FOR SALE if any is looking for one. it doesnt have the vents at the back like original because Acerbis deleted them at some stage in that fender. you can easily cut the slots in the back to make it exactly like original though