What is trail in bicycle geometry?
Trail is best thought of as the tire patch “trailing” behind the steering axis. Fork offset for road bikes usually ranges from 40 to 55 mm, generating trail figures from 50 to 63 mm. 57mm of trail is considered by many to be an ideal combination of stability and agility.
What is considered low trail geometry?
“Low-trail” bikes, designed to carry cargo on the front of the bike, have a trail figure of less than 45mm. Mechanical Trail (Front Normal Trail), describes the distance between the point where the front tire contacts the ground and the steering axis, measured perpendicular to the steering axis.
What is trail dimension?
The distance between those two points is called trail, for the simple reason that it’s the distance that the center of the tire’s contact patch trails behind the steer- ing axis. The trail dimension is given in either inches or millimeters, and varies from about four to perhaps seven inches.
How does trail affect bicycle handling?
The slacker the head angle, the shorter the offset or the bigger the wheel size, the more trail. Generally speaking, the more trail, the more stable the steering. This is because there is a restoring force when the steering is turned away from straight ahead, which acts to self-centre the steering to straight ahead.
How does bike geometry affect ride?
A longer head tube makes for a more upright position as it raises the front end somewhat. Conversely, a short head tube will lower the front end and improve the aerodynamics as the rider is put into a lower, tucked position. Therefore, this makes for a huge difference to how a performance road bike will ride.
What is negative trail on a bike?
Trail is measured in inches, and in motorcycles should always be a positive number — a negative trail means an unstable ride. Trail is important — too little or too much trail and the bike will be sluggish or even impossible to control.
What is positive trail?
The measurement is considered positive if the front wheel ground contact point is behind (towards the rear of the bike) the steering axis intersection with the ground. Most bikes have positive trail, though a few, such as the two-mass-skate bicycle and the Python Lowracer, have negative trail.