chaadster

Chainstay length is less about tire clearance these days than it is about overall feel of the bike. Shaping and construction technology allow comparatively short stays with huge tire capacity.

As for short vs. long stays, then, it’s simply about what kind of ride characteristics you want. It’s well-known that longer wheelbases smooth out bumps better, just as it is that short wheelbases change direction more quickly and crisply. Do you want or the other? Something in-between?

Personally, for a sporting road bike, short stays are a must. My favorite road bikes, from a handling perspective, both have 405mm c-stays. I have a 420mm stay bike which has noticeably more comfort and stability (at the expense of crispness), and 426mm and 444mm stay bikes which make gravel riding better. It may coincidence that the 405 stay bikes are my favorites because all the geometry elements are different, but between the two 405s, the shorter wheelbased and steeper head tubed one is my absolute favorite handler because it feels so responsive to subtle weight shifts— it steers from the hips— so I think it’s to do with weight balance, and having the rear tire tucked in underneath me is the most rewarding placement.

The 426mm stays bike, by the way, is titanium and will take 700x45c rubber.