Originally Posted by oldnslow2

I'm 200# and don't race.

I just ordered a new bike with Zipp 303 and Zipp says that 25s are more suited for them than 23 due to the transition from rim to tire.

My bike for the past 3 years has Easton EC90SL with 23mm GP4000s. I've been running 120# rear and 110# front. What do you think a good starting point will be for 25mm?