Shorter handlebars can give you more control of your mountain bike or make it easier to maneuver through narrow gaps. You can save the time and cost of installing custom accessory bars by cutting down the existing bars. Anyone with the aptitude to remove bar ends, handgrips and brake levers can cut their handlebars using a copper tubing cutter. When a tubing cutter is not available, there's another method available. The job goes more smoothly with the help of an assistant to stabilize the bike and the handlebars.
Remove the bar ends, grips and levers. Sit on the seat and grip the handlebars at the desired width. Mark the preliminary points for cuts at each end of the bars with a felt tip marker.
Measure the distance from the center of the steering headset to each mark. Adjust your marks so each is equidistant from the center of the headset.
Position one edge of a 1 1/4-inch hose clamp at one of your marks as a cutting guide. It’s not particularly important which side of the mark the clamp is positioned, as long as it can be tightened securely. Tighten the clamp with a screwdriver or nut driver.
Put on your work gloves. Align the blade of a hacksaw with the edge of the clamp at your mark. Cut the bar using slow strokes for the best results. Hold the cut end stable with one hand as you finish the cut. Repeat on the other side of the handlebars.
Secure the hose clamp to the bars at the other mark. Use slow strokes with the hacksaw to make the cut. Hold the cut end stable with one hand as you finish the cut.
Remove any burrs from the cut ends of the handlebars using a flat file. Reattach the levers, grips and bar ends to the handlebars.
Cut off a smaller amount at first if you’re unsure of the length you want. Take your time and make precise cuts.
Do not attempt to cut carbon fiber handlebars with a hacksaw.