I have the same inseam, but I'm 2cm shorter (google for inches ;) ). I need the M of the Speedconcept. Tested both the M and the L, and L is waaaaay to big for me.

Also sat on an Argon. Two different types. S is too small. M does fit (but only sat on it shortly, and never tried a L, whick will be too big i recon)

I wouldn't trust an online general sizing chart and would always try to test the frame (unless you got stack/reach number that were professionally measured). I test the frames from people I met at races and friends that have those bikes. Most people are helpfull if you ask for a short test-ride.

So, to be shot. Get a fit, or try riding the frame in the two sizes, or just buy the M based on my opinion ;)

Just so ya know, i misread that as "Help with flirting"

There's gotta be a thread on that around here someplace

Carry on

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I am also looking for some guidance on a Speed Concept frame size.
5'11 with 32" inseam.
What size frame would fit best. medium or large?
Any help would be great.

What are your fit numbers?

Man, I spent so much time researching this before I bought my speed concept. I am 5'9.5 and inseam a touch longer than 32 inches. I am on a size large speed concept with 160mm crankset. I don't think the medium would have had enough reach for me as I am pretty much maxed out as is on the large right now. I spent so much time trying to figure out what size was right for me. The shop I purchased form ended up helping me out. If it weren't for them I would have ended up on a medium. I posted a thread a while back to help me get a better fit. This is it:

https://forum.slowtwitch.com/forum/Slowtwitch_Forums_C1/Triathlon_Forum_F1/Bike_Fit_Critique_-_Please!__P7052166/?search_string=nickjo#p7052166


Keep in mind, I was fitting for long course.

Thank you for the insight and help.
I roughly measured my old Shiv Geometry at 450 reach/660 stack.

Wouldn’t have thought in a million years that you’d get on with a medium SC, unless you have some physical impairment.
I’m 5’9” on a good day, and in standard guise, it was borderline.
Mono plugin has helped quite a bit but you shouldn’t have to do that...

There's a difference between "sizing" and "fitting". One is arbitrary, S M L etc, and one is definitive and prescriptive. Generally, I find that the bike companies mis-prescribe bike sizes because their system is based on height and inseam which doesn't always correlate, and also under prescribes because of conservatism or industry inertia. Your fit is based on your fit coordinates in the aero position, for triathlon, not UCI limited, not limited by inseam or whatever the bike companies are telling you. You choose the longest bike possible that's still low enough, and that doesn't translate at all to simple inseam methods.

As someone else said, what are your fit coordinates?

E

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Aerodynamic Retul Bike Fitting

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