Originally Posted by Run1stRide2nd
I have a cervelo as well.
I'm also 5'8 with a 30.5" inseam (it's true!).
My road bikes are all 54's
My Cervelo is a 51, and fits like a glove.
Go to a qualified bike fitter and test ride the 51 properly setup, you'll be surprised.
Enjoy.
I had to double check to make sure I didn't make this post. 54 roadie and a 51 P2 SL
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Fredo, you're my older brother and I love you...but don't ever take sides, with anyone, against the family again...ever.