Cervelo P2 Size dilemma

I realize it’s impossible fit someone or nail their ideal bike size over the internet and that’s not really what I’m looking for.
I’m seeking a second opinion after a confusing and somewhat unsettling fitting experience I just had with a local well known and respected bike shop here in New England.
My dilemma comes from a visit to a local shop to buy a Cervelo P2. I went in thinking I would fit nicely on a 55cm, 700c frame, but came away told I would be much better off on a 52cm frame. I’m concerned that either I don’t have any clue about my position and bike fit on a tri bike (which could definitely be true), or that the person sizing the bike to my needs didn’t understand tri-bike geometry and/or how to position someone on a tri-bike. Or we’re both out to lunch.

Here’s some info:

* I'm 6'1", 180lbs, 88cm inseam and normally proportioned body.  I have pretty decent hamstring flexibly. 
* I come from primarily a road racing background with the last few years racing mt bikes and cross racing. (20years of riding experience)
* Started racing Duathlons last year and this year wanted a bike specific for Du's. 
* Currently ride a 59cm ti road bike (57.5tt with 73deg seat and head tube)

I test rode a 55cm Cervelo P2, liked how it felt, shop fit me using a Serotta size cycle. He started the fit using a 78deg seat tube, but for some reason abandoned it and went to a 75deg set-up. (I think he didn’t like where the plum line from knee to the pedal was falling) After tweaking and adjusting he said that I would need such a small stem (70mm or so) and that my weight distribution would be heavy on the rear and unstable/light on the front. They recommended I would be much better on a 52cm. This seems really small to me especially when you consider, I’m 6’1" and they’re recommending the smallest 700c frame size Cervelo makes for the P2k. What kind of people are using 55’s, 58’s or 61’s??? They are ordering a 52 for me based on their numbers. I want to support this local shop as they the only Cervelo dealer in the area but this just felt all wrong to me and my gut tells me something’s not right.

Sorry to ramble on, but I’m really confused on what to do.

That sounds a bit off the wall. That would be like trying to put my 5’9.5", 82 cm inseam body on a 48 cm frame, which is what my 5’4" wife rides. I’d definately get a second opinion. You should email Gerard directly at the Cervelo site.

That’s what I was thinking. I went in to this shop with some basic ideas of what I was looking for (fit wise) but didn’t want to tell this guy how to do his job. I really wanted to just let this guy do his thing and see how I felt at the end, before purchasing. I emailed Gerard a few days ago, but haven’t heard anything yet.(he’s out of town) I dropped a line to Cervelo this morning also. I’m temped to just pay for the fitting and walk away.(not satisfied) I’ll have to travel a little more to get to other shops that are Cervelo dealers or do the mail order thing (not my first choice). To be fair to this shop, I understand they have not carried the Cervelo line very long.

A bike is a financial investment. It’s best to get it right the first time. A friend of mine (who wouldn’t listen to me) went out and bought the wrong bike at a shop where they didn’t know what they were doing. He sold it a few months later for a $600. loss.

No way that would be the right bike for you. I am 5’ 8" and ride a 51, but I am wondering if I would be better off on a 54. I have very short legs, 79 degree seat angle. No way a 52 is right for you.

I am 5/8, 31 inseam and ride a 54 P2 in a steep configuration. Other ride is a 52 Trek (tt of 53) Both fit fine, with very few spacers, no excessive seat tube exposed on either. I really doubt a 52 P2k would fit you.

Cerveloguy,

I’m interested in a '02 Soloist in 51cm. I’m a 5’4" male and would normally ride about a 520-525mm top tube. I don’t have a local Cervelo dealer and am attempting to get a feel for whether a 48cm or a 51cm would be better for me. As your wife and I are similar heights, would you characterize your wife’s build as a traditional woman’s build, longer legs and a shorter torso? I know the P2K is a different bike, but I’m just trying to get your input to narrow down my sizing considerations.

Thannks in advance.

My wife is on P2K. She has long legs and a short torso, even by female standards. Going by her leg length, she would ride a 51 cm, but with her short torso would have been stretched out too much, so we went to one size smaller after some careful measuring at the bike shop.

My guess is 51 cm is probably right for you. The standard frame size formula is to measure your inseam and then multuply by .67 to get your theoretical frames size. To do this properly have an assistant help. Wear your bike shorts and sock feet standing with your back against the wall. Put a book tight up against your crotch with your feet a few inches apart. Have an assistant measure this in cms and then multiply by .67.

You might also want to email Gerard on the Cervelo site for his recommendation once you’ve got your inseam measured.

texicans, this website gives a good explanation of what I was talking about.

http://www.coloradocyclist.com/BikeFit/index.cfm

texicans, a couple more things. I looked on the Cervelo site and the geometry for the 51 cm Soloist has a 52.5 cm top tube. My guess is the 51 cm size is bang on.

There is also a 51 cm Soloist listed on ebay right now at $1800. CDN (about $1200. US)
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3603440371&category=7298

I’m 5’11’’ with a 33.5’’ inseam and I ride a 55cm P2K. For comparison, I also ride a road frame with a 57cm TT and a 120mm stem. I don’t think you would want to go any smaller than 55cm for the Cervelo.