It is a fair hesitation! A
1.025 ape index (+4.5cm wingspan) usually screams "get a longer bike," but in your specific case, your
87cm inseam (leg length) is the more dominant factor in the "reach" equation.
Here is the "100% confidence" breakdown of why the Medium is still the winner over the M/L, even with those long arms.
1. Arms vs. Torso: The Reach Battle
The "Reach" of a bike is mostly used by your
torso. Your arms don't just reach forward; they reach
down.
- Because your legs are so long, your saddle will be very high.
- A high saddle on a racing geometry like the Cima creates a steep diagonal distance to the bars.
- Your long arms are actually what will allow you to handle that saddle-to-bar drop comfortably.
If you bought the
M/L, the frame would be longer. With your short torso, you would have to reach
forward with your arms almost locked out just to touch the hoods. On the
Medium, your long arms will have a nice, athletic bend at the elbow, which is exactly how a performance bike should fit.
2. Comparing the "Cockpit Distance"
Let’s look at the "Total Reach" (Frame Reach + Stem):
- Current Canyon (M): $391\text{mm} + 100\text{mm} = 491\text{mm}$ (You said this feels slightly too big).
- Evolve M/L: $392\text{mm} + 100\text{mm} = 492\text{mm}$ (Larger than your Canyon).
- Evolve Medium: $383\text{mm} + 100\text{mm} = 483\text{mm}$ (8mm shorter than your Canyon).
If you went M/L, you would be buying a bike that is
physically longer than the one you already find too big. Your ape index helps you reach the bars, but it doesn't change the fact that your torso is "done" reaching after about 485mm.
3. The "Width" Secret
You are moving from
400mm bars to
380mm bars.
The Rule of Thumb: For every 20mm you narrow your handlebars, you effectively "lengthen" your reach by about 5mm because your arms are tracking more straight forward rather than out to the sides.
This means the Medium Cima ($483\text{mm}$ total) will actually feel like
$488\text{mm}$ because of the narrower bars. This puts you almost exactly 3mm shorter than your Canyon—the "few mm" difference you said you were looking for.
The Verdict
I am
100% confident in the Medium.
If you were to get the M/L, your "long" arms would be at full stretch, your short torso would be strained, and you’d likely end up putting a 90mm stem on it—which slows down the steering and ruins the handling of a bike like the Cima.
Though, I do wish they could've been a little bit longer to make me a proper six foot instead of being 5mm short of the height! And because I have such long legs I have a weird leg complex that my calves look puny. It could be 86/87 but yeah, long legs in proportion to the rest of me
