Just curious if there is a handy formula, like with increasing saddle size and knee angle that can be applied to shoulder angle? Like X cm change in reach will lead to Y degree change in shoulder angle.

What, are we all the same?

i'm also pretty sure the saddle/knee thing doesn't work the way you think it does.

Maybe it'd be better if you just explained what you're trying to achieve.

Well I measured my shoulder angle and it's around 77 degrees, was hoping to get it up closer to the more "ideal" 90 degree angle (I was getting some tightness in between my shoulder blades). In looking at the video I took, my elbow could stand to go up and forward to achieve that. My quill stem is already at it's max height, so just thinking about going the adapter/stem route.

There's a local shop that does a la carte fit sessions, prob will go there for this, I've got other projects draining my mental energy, don't need to expend it on this!

Okay, well, good luck.

For the record, in case it's helpful to you or someone else, although I don't know what you mean by "shoulder angle" nor understand why 90º of it is ideal, tightness between the shoulder blades suggests more of a too-wide grip stance, as from handlebars that are too wide.

Do let us know how your a la carte (?) fitting goes.

There is no simple formula because the angular change will depend on your torso and arm lengths primarily, secondarily on things like saddle to bars drop and then to need to take into account hip flexibility and so on. If you ignore these last items, then you get to use the law of cosines...

However, there are still questions as to what you are looking for, as chaadster points out.

Sorry for the vagueness, I was referring to the 90 degree angle between the shoulder, elbow and back that I've read is kind of the happy medium for more casual road cyclists. My quill stem is at its minimum insertion point, so I can't raise the stem anymore, which is one thing I think would help. Maybe someone with a good eye can see based on this image how my reach is.

Chaadster, to your point, I have read that tightness between the shoulders can be from a too wide stance, but I've also read that trapezius tightness can be as a result of too short of reach.

My quill stem is 110mm, but I'm still not crazy about the long, low reach to the hoods on this older style bar (seems like having the bars turned up actually make my trapezius muscles tighter, that's why I think it's a reach thing, they're less tight with the bars as seen in the photo). So I've got a number of variables that are probably best handled at a shop with an objective set of eyes. But going by basic geometry, I think I need the bars a little higher and my reach slightly extended to get to that 90 degree shoulder angle I referred to earlier

"Shoulder angle" is not a meaningful fit element to me, in the sense that I've not heard of it nor used it, so leaving that aside and looking at the pic, I'd just say to put a 90mm stem on there, probably negative 6º.

Hate to belabor the point, but here are some links to this whole "shoulder angle" thing I'm talking about BikeFit - Road Bikes How To Perform A Basic Bike Fit - YouTube BikeDynamics - Bike Fitting Specialists - Fit Guidelines

From VeloFit Revolution - Blog - The 5 Most Common Bike Fit Issues, Part 4 of 5: Reach to the handlebars -*guidelines. "1. Shoulder angle while in the hoodsThis is the angle formed by the hip, shoulder, and elbow. If this is greater than 90 degrees, it's a pretty good sign that the cyclist is too extended; less than 90 degrees would indicate a position that is too bunched.

Thanks for sharing that; I now understand what you were talking about.

Like Chaadster I'd never heard of shoulder angle either. There are other established 'tests' for fit that we all are familiar with and maybe you could do one or more just for grins, and who knows it might even allow one of us fossils who aren't down with Generation X speak to help you. Have you tried locating your front hub when on the hoods? Is it hidden by your bars? In front? Behind? With your elbow against the nose of the saddle, where does the tip of your middle finger land on the bar? Does it reach? The 90mm stem will work but what I did was get a compact bend (Civia Emerson) with an 80mm reach instead of the 100mm reach that was causing me grief. What is the reach of those bars in the picture? FSA Wing Pro's are a compact bend as well and I have those on another bike. Worth a try.

H

My "shoulder angle" changes all the time with my position -- it can be ~90 degrees when I'm dodging a headwind in the drops, but it's often not. "Shoulder angle" sounds like one of those BS metrics like KOPS that came from observing a lot of bike riders, not from anything logical.

The picture shows someone who is sitting upright on the saddle, bending their back rather than rotating their hips to lean forward. Once that's fixed, some more "shoulder angle" should magically appear.