Cassatte Ratios????

It depends on how flat the courses are.

I don't thing there are to many big climbs in any that I have planed (I hope) Fairly undulating though..

Unless you have a compact crank up front, I would actually go for a 12-25. That's a good middle of the road cassette. I would only go smaller if you are extremely fit, or never ride hills.

I train on either 12-23 or 12-25. For most road races I use 12-23, for most flat crits an 11-21. Mountain events are either 12-25, 12-27 or custom 13-28. Of course I have about 6 sets of wheels, but if I you had to pick one, I'd go with a 12-23.

Mlimacher said:

This is my first year racing on the road. I am currently using a 12-23 sram cassette. Should I use a 11-21 for racing? I was looking for a new dura ace one but wasn't sure weather to change the ratio for racing as I have trained with the 12-23???

Shouldn't you be the best person to answer this? Ride the race course and compete a few times and you should be smart enough to work out if your 12-23 has the range and spacing for your needs. I can't see how anyone else can tell you what's best without knowing your ability and the course you race on.

if it's a flat course, you might as well get the 11/21, because you won't be using the 23 in a criterium 🙂

The last race I did we got to ~55kph with a strong tailwind just about every lap, and I don't like 'pedaling', so I spent a bit of time on the 53/11, which is ~90 rpm

What sizes are the chain rings? I'm currently using 53/42 11-25 I'm going pretty fast before I get into 53-11 and only use it for sprints if its slightly down hill.