Talking about cassettes what ratio should I get on my disc wheel for TT's.
I have got a 11-23 to go on there but I keep hearing talk about 11-21's which would mean nice close ratio changing to help keep the cadence similar when changing.
But one challeng with the lenticular disc wheel is that I have noticed that the jockey wheelcage on the rear deralier is touching the disc on the largest rear cog of the rear cassette.
Although I probably won't be using this gear much in TT's if I adjust the inside limit on the deralier so it doesn't rub on the disc then on the large front chain-ring it won't shift into the large cog on the cassette and in the small front chain-ring it does shift but is noisey thereafter.
Any Ideas on this one because if I do fit a 11-21 cassette I will be realistically riding a 11-20 if the disc keeps getting in the way