I have a road bike (2010 Specialized Secteur) that I have just bought a new rear wheel for so I can easily switch between road and turbo trainer use. So I need to buy a rear cassette. The current road wheel (Alex 500) has a Shimano HG 50 8 speed 13/26 cassette fitted. The wheel bought for the turbo trainer is a Shimano 501 and when I go to order I can see that I can buy the Shimano HG 50 8 speed cassette as 12-21, 12-23, 12-25, 13-23 or 13-26. If I buy anything other than another 13-26 for the turbo trainer will there be any issues regarding chain length or gearing ratios or could I buy any of these configurations and happily switch between my road wheel and the wheel for the turbo trainer. Thanks