1. It is either the screws or the handlebar or fork steerer clamps that break. Therefore, check the clamping areas for cracks regularly 2. Every handlebar area wrapped or clamped can generate a breakage. In the case of the Beast Flatbar there was a breakage at the brake lever clamp. Therefore, be sure to use a torque wrench for tightening fittings with the torque wrench and only in a way that they do not turn during the ride. 3. Further weak points are bendings. The FSA SL-K broke three times in the same area. 4. Narrowing can also be the weakest link in the chain. The Truvativ-Kyle-Strait aluminium handlebar cracked three times close to the stem clamp.
Health is valuable, safety an expensive commodity. As expert witnesses we know that MTB handlebars and stems have caused the crashes of many cyclists in the past years, some of them with partly dramatic consequences. In the mid 90s already the special interest magazines of the German publishing house Delius-Klasing Verlag showed a reaction and conducted basic research together with universities. The research resulted in a first serious mountain bike handlebar test published in the October issue 1995 of BIKE.
The current test is based on these findings. Further theses were continuously assigned in cooperation with universities and the test procedure was permanently adjusted to the sport which developed and differentiated at a rapid pace. The tests not only focus on the level of forces measured, but also on the question how often will an incident act on a handlebar during its service life. The test that we conducted for BIKE not only considers typical cross-country or marathon rides, but also failed riding manoeuvres, drops and hard jumps. We assume in particular that a mountain biker will not replace his sinfully expensive handlebar after having gone down. For this reason usual falls are considered. In my opinion the test results are a complete success, because more and more manufacturers create a dense quality at highest level to the benefit of the mountain bikers.