Posted by: Endur-Bro
Can someone explain how short chainstays climb better?
To climb effectively you need two things:
1) enough traction on the rear wheel to make use of the power available.
2) front wheel stays down so you can steer and don't loop out.
If you have a problem with either ^^^ you don't climb well.
- As you move the rear wheel backwards [longer CS] you are moving it away from the rider's CG [assuming everything else stays the same] so there is less weight on it and that results in less traction. But, that also means more weight on the front wheel.
- Conversely as you move the wheel forwards [shorter CS] you are moving it closer to the rider's CG [assuming everything else stays the same] so there is more weight on it and that results in more traction. But, that also means less weight on the front wheel.
- My body type carries most of its weight in the upper half so my front wheel is easily weighted and it's hard for me to weight the rear wheel. I never loop out on a bike when climbing for example even with very short CS. However, it's really easy for me to spin the rear tire on a bike that doesn't have short CS because that wheel is not close enough to my CG.
- This situation is made worse by longer bikes [moving bars forward] and steeper STAs [moving CG forward].
- One solution is to shorten the CS. Brings the rear wheel closer to CG and improves traction.
- Another solution is to slacken the effective STA such as with an offset seatpost. Moves CG backwards.
- Final solution is to bring bars closer such as with a shorter frame and/or high Stack. Moves CG backwards.
- Not shockingly my bikes combine some or all of these factors because that works for me.
Now this ^^ all relates to the rider's CG. That's why you have a bunch of people saying they climb better with short CS, a bunch who say they climb better with longer CS, and a bunch who don't care about the topic because most bikes just work fine for them. They are all right.
Last edited by: Vikb on Sept. 23, 2023, 6:35 a.m., edited 2 times in total.