Cutting Bike Handlebars

This article will walk through the process of how to cut/resize flat bars for bicycles.

1

Getting Started

What Tools do I need?
  • Ruler or other method of measuring cutting depth
  • Marker or way to mark cut point
  • Hacksaw with appropriate blade
  • Saw guide such as SG-6 (metal), SG-8 (carbon) or SG-7.2 (universal)
  • Foaming cleaner or soapy water (when cutting carbon)
  • File or deburring tool (metal) - or - sandpaper or emery board (carbon)
  • Rags
  • Protective glasses

When choosing a new handlebar width, be conservative. It is always possible to remove more later. Also be sure to reduce width evenly — when shortening bars by 40mm total, cut 20mm from each side.

Bar material is an important consideration when selecting tools and sawblades. For aluminum, steel and titanium bars, a metal cutting blade with teeth is ideal. For carbon fiber bars, a carbon compatible blade is most effective. If you don’t have a carbon compatible blade substitute a higher-toothed (32tpi or higher) steel blade. Regardless of blade type, double check that the blade is adequately tight in the saw.

Cut Bars Steel Blade

A traditional metal blade is sufficient for most metal bars

Cut Bars Carbon Blade

A carbon-specific blade results in a cleaner cut on carbon bars

NOTE: Carbon dust is harmful to your lungs. To avoid health problems, apply a foaming cleaner to the cut point before cutting. Reapply to the cut point regularly throughout the procedure to prevent dust from going airborne. You can use soapy water, but foam such as window cleaner or shaving cream is most effective.

Cut Bars Foam

Foam will trap the carbon particulates and prevent them from going airborne

2

Cutting procedure

It is ideal to do the process on one side at a time. This way the placement of the controls can be easily referenced after each cut.

First, remove the grip from the handlebar and move the controls inboard. Measure and mark the cut point. Typically, it is sufficient to be accurate down to a few millimeters — this is not a precision procedure.

Cut Bars Move Inboard

Move controls inward to allow space to work

Cut Bars Measurement

Mark the cut point with a marker

Install the saw guide and position it so that the blade sits on the reference mark, and tighten it down.

Cut Bars Install

Cut Bars Align

Begin cutting. Metal hacksaw blades are designed to cut on the push, so add some pressure going forward, and relieve pressure going back. A blade for carbon fiber is non-directional.

Cut Bars Push Forward

Push down on forward stroke

Cut Bars Pull Backward

Ease up on backstroke

Once the blade is almost completely through the bar, ease up on pressure for the final strokes — this will result in less of a burr.

Remove the saw guide. For metal bars, use a file or deburring tool to clean up the end. For carbon bars, emery cloth or sandpaper are your safest options.

Cut Bars File

Cut Bars Emery

Reinstall the grip. Reposition the controls to duplicate the position of the opposite side, and torque the control fasteners to the appropriate torque specification — typically about 4–6 Nm. Repeat the entire process on the other side.