# TT Sizing



## Reventon (Aug 4, 2008)

Greetings everyone,
I am looking to purchase a Cervelo P2SL (2008) online and am having trouble matching the sizing. This will be my first tt bike and there aren't any Cervelo dealers close to my home. I currently ride a Specialized Tarmac Pro with a 54 inch top tube. I am unsure if I should get a 51 or 54 frame. Any suggestions?


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## STARNUT (Jun 19, 2005)

Are you going to ride it in the 78 deg STA?

Starnut


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## Reventon (Aug 4, 2008)

I'm not sure about the set up for a tt, but if I do run it at the degree the top tube would be around 54. Is that angle to upright?


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## teffisk (Mar 24, 2006)

I got one size smaller than my road bike in the P2SL and it is definitely the right size. My friend who the same size as his road bike had to sell his because it was too big.


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## ksanbon (Jul 19, 2008)

Competitive Cyclist sells Cervelo's and has a great on-line fit calculator.


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## OneGear (Aug 19, 2005)

i ride 54 road as well. the 54 P2SL in the 75deg position is 557mm i believe. That's too long for me, but I have been riding that for the past year. It's about 1cm too long for me with a 90mm stem and seat slightly forward. 

It's probably fine in the 78deg position (haven't tried it), but I would get the 51 so you have the versatility of a good fit on both.

Starnut is very knowledgable in many brands and Cervelo is one of them, I'd wait to see what he has to say about this.


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## STARNUT (Jun 19, 2005)

*IF* your going to ride it in the steep/78 deg STA I'd get, _at a minimum_, the same size as your road frame. Typically I ride/sell frames one size large in TT frames if your going to be foward. IE I ride a 54 road frame from Cannondale and Cervelo and would buy a 56 Cervelo or a 58 Slice because I would/do ride them about as far foward as I could get them. 


You cannot look at TT alone you have to take STA into account as well and thus "reach"

Starnut


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