Older shimano 7 speed hyperglide cassette
My old Trek 560 has an ultegra 600 RD, 7 speed shifters, and a 7 speed hyperglide cassette. As I understand it, 8,9, 10 speed cassettes are not compatible with the 7 speed hub - Is that correct? (It originally had a 6 speed 105 freewheel on it but I changed out the original wheels, RD, and...