Facebook Twitter LinkedIn Pinterest Bluesky Threads Why is there a bolt between the seatstay and chainstay? by VastFix3446 Bicycling Biking Cycling Mountain Biking
Switchen on June 25, 2025 2:52 pm Because it’s a suspension pivot. The chainstay and seatstay actually pivot there as the bike moves through it’s travel.
mouse5422 on June 25, 2025 2:54 pm That is a pivot point. The frame has to be able to pivot there or the suspension wouldn’t work. Some full suspension designs don’t need it, some do.
MyBeaverHurts on June 25, 2025 2:55 pm It turns it into a horst link/4 bar suspension from a single pivot. [If you want some reading Here is a good one on the differences ](https://www.theproscloset.com/blogs/news/a-basic-guide-to-the-most-popular-mtb-suspension-designs)
surfoxy on June 25, 2025 2:57 pm Others have answered, I would only add that it has a slight weight penalty, and there are “flex stay” designs like the Transition Spur which remove this pivot.
4 Comments
Because it’s a suspension pivot. The chainstay and seatstay actually pivot there as the bike moves through it’s travel.
That is a pivot point. The frame has to be able to pivot there or the suspension wouldn’t work. Some full suspension designs don’t need it, some do.
It turns it into a horst link/4 bar suspension from a single pivot.
[If you want some reading Here is a good one on the differences ](https://www.theproscloset.com/blogs/news/a-basic-guide-to-the-most-popular-mtb-suspension-designs)
Others have answered, I would only add that it has a slight weight penalty, and there are “flex stay” designs like the Transition Spur which remove this pivot.