Apologies as i know this is always asked on here. I'm about to push the button on a planet x sl carbon bike (medium/52) and i'm not sure what stem and bar width to choose.
Based on ribble's sizing
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I need a 110 stem and a 44cm bar width. According to the lemond system:
Total Reach = [(Torso Length + Arm Length) / 2] + 4 inches = (Top Tube + Stem)
My stem should be a whopping 220cm!!
For info I'm 5'9 with an inseam of 32"
I know i should check at a LBS but I feel a bit guilty as I'm not buying from them.
44cm c-c is the widest common size - go on your shoulder width (you'd need to be broad to need them on a 52cm bike, assuming that's the correct size)
As for stem 110 doesn't seem ridiculous. Just get it and you can change it later
How is it best to measure shoulder width? From the knobbly bits on the top of my shoulder the width is 38cm but if i measure from the outside of my shoulder it's 48cm. If i hold the tape measure to 44cm it feels about right?!
you need to know the effective top tube of the planetX and the ribble then you choose the stem to get your overall length (and change the frame size if the stems end up really long or short). if you don't know your ideal ETT+stem length then you are clutching at straws ordering a bike over the internet imho.
wide shoulders = 44cm bars (c-c - i.e. 46 on above guide)
med = 42cm
etc
If you hold your arms out roughly parallel and measure between your hands what is the measurement? Is it comfortable?
classic in-built inaccuracy there mhuk!