One size small frame with one size longer stem vs larger frame with smaller stem?

Folks rediscovered this forgotten gem and remembered why I came to love cycling tips in the first place. Oh the good old days :slight_smile:

FWIW - Cervelo have a 48cm Aspero.

Anatomically I am the opposite to you - long legs and short(er) torso. This means I need to jack up the seat post and prefer a shorter top tube. I ride 56cm Cervelo’s and Specialized, but Treks dont support the saddle height I need so had to ride 58cm. I like the darty/responsive turning from the 56cm frames.

Edit: I should have mentioned that I downsized from 58cm Cervelo and Ridley frames to 56cm to get the right feel.

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rag.tag… I have the EXACT same dilemma… For the first time in years I downsized from my usual size 56 to a 54 (on a new Specialized Crux gravel bike). On paper (Geometry geeks) this made sense, however in the real world, I need to do a bit of work to get it dialed. I do think ‘most’ people (expereinced riders but not fit professionals) can be fooled at times by the black magic of geometry numbers.
I went down a size as my Large (56) Scott Addict Gravel because I felt a bit too stretched out despite having a long torso and short legs. Had that feeling like steering a long ship. So when Specialized redesigned the Crux with the usual longer lower geometry I thought this was my chance to go to a 54 and be able to ride with a normal amount of seatpost height (hopefully to help w vibration dampening) and to aid in actual single track handling/agility. However, the reduction in stack was a bit too extreme such that the bike was killing my upper body on long rides and the front end was squirrely when I stood up to pedal. It felt like my center of gravity had moved too far forward. I swapped the -6degree 100mm stem for a +6degree stem 110mm stem to get the bars up a bit - have not had a real chance to test it but looks good so far (saddle to bar drop is a bit more to my usual measure).
I do worry that I have made a mistake and should have bought the 56 and its higher stack - but I have some swapping to do before settling on that conclusion. Most modern geo seems to be moving the rider back a bit of front/center. I do see that pro’s almost always prefer a smaller frame with a longer stem… apparently, it is actually more stable (not what I would have thought! I just hope that I can find the right balance in stability/agility as I want to ride this bike in new style gravel events that incorporate proper singletrack. My original thought was a smaller frame would help here - but with such lower stack, I am not sure…

This is me as well. long legs, short & somewhat thick torso. Seatpost goes up so I need a shorter TT to keep reach within reason. Also, going to a slightly more upright frameset like the Caledonia or Roadmachine helps to keep my saddle to bar drop in check. On race bikes, it’s easy for me to end up 10+ cm of drop which just isn’t practical for everyday riding for me.

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So before the bike you aligned everything up in geometry geeks and still have had that wonky feeling? This is what I am afraid about. On GG the longer stem lines up perfectly with short stem on longer frame. I am just jittery how this will actually translate in real life.

As I read his post, his new stack height is lower than his previous position (see his comment about flipping the stem). If that is the case, then having a different handling bike is to be expected.

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Spacers do not only affect stack, but also reach. Because spacers extend the fork above the frame. Which implies that the fork/head tube angle plays a role when it comes to the effect on the reach.
Following this reasoning, a different head tube angle can also mean that the same stem length and angle feels differently on 2 frames that have the same reach.

Furthermore, 2 frames can have the same head angle, but will steer differently if the forks have different offsets. Because the amount of trail will be different. (Not even taking into account wheel base differences, nor center-of-gravity differences because of BB height and the split front/rear center and the body position on the bike. The latter is also rider dependent, of course.)