You need to know the stack and reach of the bike to see if it fits. I’m 6’1” on a medium Trek TTX. love my TT bike. Fits great.

I'm the other way, all legs and no spine. 6'4", but my stack/reach works better with a medum or large. The seatpost height is sky high, but that's rarely an issue on any medium or large. For too long I assumed I needed XL frames and ended up too stretched out for MTB/Commuting. In your case then you sound as if you are struggling the other way, in that your back is so long that coupled with the short seat post you are needing to go longer on the stem.

Others wll have more detailed views, but for me, seat height which is governed by leg length is pretty much an irrelevancy for bike fits, there is massive adjustability there. The back length (or hip to shoulder) is really the key length. On road / MTB that's a pretty good proxy to top tube length and frame size. In the case of bikes with stems you've got 50mm +/- to play with by swapping out stems before odd things happen with handling. On tri bikes then that's achieved by moving the pads forward / back. So your challenge may be that the frames for your length end up without the drop between saddle and pad that you want. I'm the otherway, where because my saddle is sticking out the top of the frame by a foot then I end up with a very big drop - great for aero, could be hard in a few years or if I didn't have the flexibility I do.

It's a bit of a trade off Medium vs large.


Lately I have been gravitating to larges.

Riding a longer wheelbase is nice for a change. Shorter is more darty & responsive.

Keep in mind when the seat post is jacked (I have long legs) it moves the seat back quite a bit in relation to the BB.

---

Training Tweets: https://twitter.com/Jagersport_com
FM Sports: http://fluidmotionsports.com

Nope

I'm 6"2' and I'm on a XL. Used to be a L but that was causing fit problems and a hunched back. I'm all leg with a short torso and I can't imagine being on a M. You need to know your stack and reach numbers before you buy. Getting a good deal on a bike that really doesn't fit isn't a good deal.