Originally Posted by
calstar
Trek Crosspoint cf frame and fork, too much steerer(cf) for safety(failure), any "rule of thumb" for what stack is acceptable above headset?
the rule of thumb I always heard for carbon steerers was « spacer stack no taller than the diameter of the steerer » therefore 25mm for a 1 inch steerer, and 30mm for a 1 1/8 inch steerer. This doesn’t factor in long vs short expander plugs which
may contribute to steerer rigidity. I run 20mm of spacers on a 1 1/8 inch CF steerer. In addition, the top ~3 inches of the spacer is solid - filled with epoxy with the expander plug encapsulated - makes the upper portion of the steerer more rigid and crush-resistant.