Help! - My LBS is clueless - Need framesize feedback

I'd strongly recommend buying your bike at the shop that is going to fit it. I wouldn't buy it then drive to get it fit.

What happens if you end up with the wrong size bike will they take it back?

Working directly with the fitter is better as they often will swap out parts even money if you need different size stem or other parts and will save you money in the long run.

If the specialized fits you well, chances are the Cervelo will not fit quite the same, and vice versa. Your shop should be able to eyeball you onto the right size frame, even if they can't do a FIST or a RETUL fit.

You can also take a picture of yourself on all three bikes on a trainer, and then come home and look at them, if you're really feeling unsure...you can def. get a rough idea that way. Dialing a fit in is a science, but picking the right frame size isn't...

I think a bunch of options are out there for you if you are willing to travel.  I second the advice about getting fitted while (or before) you make the investment of buying a new bike. 

Where are you located? FIST is everywhere now-a-days and Retul is in Colorado but seems to be growing in many other states and countries, too.  Another option is Fit Werx. They're on the East Coast.

First - I don't know much about tri specific bikes... but...
with road bikes, the top tube length is perhaps more important than than the seat tube.
You need to find the bike that will facilitate the ideal fit for your body type.

Seat height is easily adjusted.
Top tube, not so much... fitting your torso envolves swapping stems and other hardware that could impact bike handling and balance if more than just minor changes are required.

Focus on top-tube length first, then seat tube second.



Edited by TaylorB 2009-09-14 7:33 PM

Competitive Cyclist has an online calculator for bike fit that is pretty thorough. There is a seperate fit calculator specific to Tri/TT bikes... here's a link to their Tri Bike calculator:

http://www.competitivecyclist.com/za/CCY?PAGE=FIT_CALCULATOR_INTRO&INTRO_LINK=NOREDIR&SITE.CODE=TRI


Edited by TaylorB 2009-09-14 7:45 PM

I can second the calculator at competitive cyclist.  The suggested bike size the calculator gave me is the same size my LBS suggested for both my tri bike and road bike.  ALSO, I was professionaly fit on both and my suggested saddle height, setback, reach, etc, was probably within 1/4" of what the web site spit out.

Maybe I was lucky, but it was surprisingly accurate.

One of issues you're facing is that you're looking for a 54cm frame... the problem is that there's no standard on what is a 54cm frame... QR geometry is very different from for example Ceverl (top tube, head tube, angles, etc.). You simply can't compare a Medium or a 54cm from brand to another... QR Medium is somewhere between a 51cm and 54cm P2C and the Specialized 56 is significantly larger than the other two you have looked at...

Don't go out spending almost $3grand on a bike that may or may not fit... demand to have a proper fitting first and then buy the bike that fits YOU. You should be the constant, not the bike in this equation...

I'm not an expert here.... but my understanding is that for tri bike fit, top tube length is probably the most important parameter (someone please correct me if I'm giving bad advice!). I would suggest using the on-line bike fit calculator suggested above, then take the information you get on suggested frame dimensions (especially TT length) and look at the manufacturers websites and check out the frame geometry for the bikes you're considering. Find the one(s) that comes closest to meeting the sizes recommended by the fit calculator. If there are a few that are close, and fit can be tweeked by adjusting stem length, saddle height, saddle fore/aft position, etc., then go with the one that feels like it has the best ride to you.

Of course, it would be ideal to purchase the bike and have it fit at the same location by a qualified fitter, but it sounds like that might be difficult for you in your location. Good luck!

You can google up a you tube video on exactly how to use the calculator. You'll need a friends help to do it properly.

Not luck. My Serotta custom fit was within the same deviation. That calculator works tremendously well for first approximation sizing.

Thanks all for the help and suggestions.  I'll start with the calculator and plan some road trips to find some stores with more experience fitting tri-bikes. 

Sounds like the right approach.

And x2 on the comment saying that bike "sizes" are nearly meaningless.  Top tube length is a better measurement.

But what you really want to use is "stack and reach", though sadly not all manufacturers have adopted it yet.

http://www.slowtwitch.com/Bike_Fit/Stack_Reach_Primer_Chapter_One_95.html

I have been shopping for a tri bike. I went to a few dealers, they eye balled me and said I needed a 54, Mostly because they have 54s in stock.

Then I went to a dealer, who's owner is an ex National Champion triathlete, and now at 45 does a 2:04 Oly.

He put me on a 54cm Felt and he said it didn't fit. He did not have any Cervelo's in stock.

But he had this gadget (bike) that all the tubes can move and he could simulate all sizes, angles....even other bikes like The Orbea. All he needed was the geomtry specs and he could simulate it. Very cool contraption.

He simulated a 56cm Cervelo, a 58cm Cervelo and a 56 Felt. The 56 Cervelo fit me the best. He will order that. The Felt did not fit me.

I am only 5'10 but apparently I have long legs. He fitted me to be able to adjust the bike to be able to play between settings for sprints or half IM depending if I was looking for comfort or agressiveness.

He obviously knew what he was doing. Everyone else tried to liquidate their stock. He tried to find me a bike that fits, even if it meant not liquidating his inventory. For that one and only reason, I'll buy from him.