>>16997371 inch quills were considered too weak for mountain bike use, so later bikes had 1/ 1/8th inch quills
but there are still problems with the expanding wedge rusting in place
being over tightened, so it can damage the Head tube or the bearing races
being mounted so high as to bend the threaded section of the steerer tube
Threadless / Ahead steerer tubes can be made of lighter materials
but they depend on spacers for height adjustment unless an adjustable stem is fitted
Ahead steering tubes being absent of threads can also be cut to different lengths with less hassle
