SPROCKETS / 2 1976 – 1978 KTM 250 , 400 MC, GS front sprocket $ 25.00 1976 – 1978 KTM 250, 400 MC , GS rear sprocket $ 85.00 1980 – 1982 KTM 250, 400, 420 MC , GS front sprocket $ 23.00 1980 – 1982 KTM 250, 400, 420 MC , GS rear sprocket $ 70.00 1983 – 1984 KTM 250 , 420 MC , GS front sprocket $ 23.00 1983 – 1984 KTM 250 , 420 MC , GS rear sprocket $ 70.00 1985 – 1989 KTM 250 , 300, 350 , 420 rear sprocket $ 70.00 1976 – 1978 Montesa 250 , 360 rear sprocket $ 70.00 1974 – 1977 Ossa 250 front sprocket $ 23.00 1974 – 1977 Ossa 250 rear sprocket $ 70.00 . 1970 – 1974 Penton 125 , 175 Rear sprocket Chain size 428 6 bolt holes 50T , 52T, 54T $ 75.00 1977 – 1982 SWM 125, 175, 250, 347 , 440 C/S sprocket $ 25.00 1977 – 1982 SWM 125,175, 250 , 347 , 440 Rear sprocket $ 70.00