Stack, Standover & Saddle to bar drop
A: Saddle to bar drop
Saddle to bar drop and stack describe vertical frame measurements and relate to one another like top tube length and reach. The saddle elevation influences the rider’s seating position and determines whether a rider sits on the bike in an athletic, bowed or compact, upright position. Uphill, this position has an influence on the climbing ability of the bike. The more upright a rider sits, the more easily the front wheel will lift from the ground when riding over obstacles.
The stack in turn describes the position of the rider on the bike when standing. A low stack results in more pressure on the front wheel and increases safety in corners. Current “modern” geometries can be ridden with a lower stack because the longer reach and shallower head tube angle mean that the flip-over sensation is reduced with a shallow stack position.
Standover describes the height between ground and upper edge of the top tube at its lowest position. In this position the rider should have enough space between crotch and top tube when straddling the bike. However, standover is also of dynamic importance because a small standover allows riders to lean the bike better in corners without hitting the inside of their thigh too soon.