When you already have a perfectly good set of standard Allen wrenches in your garage, owning a torque wrench may seem like overkill at first glance. But experienced mechanics know just how important it is to use a wrench like the PRO Torque Wrench when securing critical components like your handlebar or seatpost in place.
By not using a torque wrench, you're setting yourself up for risk of under-tightening or overtightening bolts, which could result in component slippage, breakage, or worse. It’s common to hear stories of riders under-tightening the faceplate bolts on their stems and then hitting a chunky washboard descent or rocky section of singletrack. As the bike bounces around the technical terrain, the rider’s handlebar slips, throwing them over the bars and straight into the dentist's office to fix their damaged front teeth.
“The reality is that all the bolts on your bike have a torque setting whether published or not,” advises Chris Jacobson, Product Manager for Pro Bike Gear. “For some of those parts, the risk from getting it wrong is low. But with more sensitive components, especially lightweight parts such as a carbon handlebar, the margin for error goes down precipitously. So, the need to have the proper torque setting goes way up.”
No matter what your “experienced” mechanic friend tells you, it is virtually impossible to tighten bolts properly by feel alone, adds Jacobson. “In almost every case without the proper tool, we tend to overtighten small bolts (with a low torque setting) and under tighten large bolts (with higher settings),” he says. “But by using a torque wrench, you are dialing in the exact right amount of force that will hold the fastener in place to control slippage, but not over-stressing that fastener or other involved components such as your carbon handlebar.”
A torque wrench is an essential tool to own if you are going to work on your own bike. “If not, eventually you are going to break something,” warns Jacobson. “Hopefully, it's just the component, which will mean a voided warranty. But if you under tighten the stem faceplate and end up going over your handlebars because your bars slip, well, you get the idea.”
PRO Torque Wrench
Keep your bike safe and secure with the PRO Torque Wrench, which
features adjustability from 3 to 15 Nm. The Newton meter (Nm) is the measure of force that’s most widely used for bicycles and components. Look for a torque number printed on the component near the fastener in question, or consult the owner’s manual to determine the correct torque setting to use.
The PRO Torque Wrench kit includes the wrench and handy storage box, plus M3, M4, M5, M6, T25, and T30 Chrome Vanadium bits. It also features an extender for those tough-to-reach spots. That range of torque and socket selection will cover most of your basic bike maintenance needs, such as securing stems, handlebars, cockpit components, seatposts, and even cleat bolts.
How to Use a Torque Wrench
The operation of a torque wrench is fairly straightforward, but there are several important caveats. The first is to only use your torque wrench to fasten bolts; it’s not meant to be a breaker bar for removing overtightened bolts. “Doing that will actually knock your torque wrench out of calibration, which defeats the whole purpose,” reveals Jacobson. “It’s really only meant for tightening the last few percent. Never use it to remove bolts."
It’s also good to check the component manual to see if the prescribed torque measure is for a dry or lubricated bolt. If a bolt is lubricated, it will tighten more easily with less force, which could lead to an inaccurate torque measure.
After confirming the torque setting and getting the bolt in question started, install the appropriate bit on the PRO Torque Wrench. For example, install the 4mm bit onto the wrench for installing most bicycle stem faceplates. Next, set the desired Nm on your wrench by using the dial on the handle. Now, with your hand on the handle (not choked up the shaft), tighten the bolt (righty tighty, lefty loosey) until you hear an audible click, which is the signal you’ve achieved the appropriate force. Finally, when you are done, reset the wrench to zero so that it will stay calibrated.
"The bottom line is that owning a torque wrench is a pretty small investment when you do the cost-benefit analysis,” says Jacobson. “It’s definitely one of the most important tools in my toolbox.”