How Does a Torque Wrench Work: Learn A to Z

If you have no idea about how does a torque wrench work, this guide will definitely be helpful to you. When all the mechanics of a vehicle such as a bicycle are based on small anchors, screws, fittings, and connections. It is imperative to precisely adjust all of this without losing a component.

But also, not allowing excessive pressure to damage such components or parts of the bike. A torque wrench is then the perfect tool. An excessive tightening without a torque wrench damages components of your bike that are vulnerable.

If they are made of aluminum, they can be bent; if they are made of carbon fiber, they can split. Let us know how what is exactly a torque wrench and how does a torque wrench work?

What is a Torque Wrench

Torque Wrench

In a flat and direct way, we can say that a torque wrench is an adjustment and pressure tool in which this pressure value can be precisely established. So, it is neither higher nor lower. In other words, with a torque wrench, you will be able to adjust each screw on your bicycle or mountain bike with the exact pressure you need, following the advice of the manufacturers.

A torque wrench is a precision, it is careful, and it is professionalism. So, the use of a torque wrench is one thing that goes by a long time but is important in the long run. In the first place, a bad adjustment causes that the component or accessory in question moves or becomes loose once you start the ride. It can be a risk for the cyclist.

How does a Torque Wrench Work

TEKTON 1/2 Inch Drive Micrometer Torque Wrench (10-150 ft.-lb.) | 24335
  • Includes storage case and product manual with torque conversion chart
  • Wrench emits a click that can be heard and felt when the preset value is reached
  • High-contrast dual-range scale is easy to read, even in low light
  • Reversible ratchet head drives in both directions and measures torque in clockwise direction
  • Durable all-steel construction has no plastic parts to break or wear out

On paper, a torque wrench works the same as any other wrench – it is used to tighten screws. The big difference between a torque wrench compared to any other tool is simple.

Before tightening a screw, you can indicate the pressure that the screw should carry according to the manufacturer’s instructions. Thus, you will not do it by eye, under your subjectivity, and with the constant doubt of whether it is tight enough.

Its Mode of Use is Quite Simple

Before tightening the screw in question, you must indicate on its crank or handlebar which is rotating the pressure value indicated and prescribed by the brand or manufacturer. A torque wrench specifies these torque values ​​to give you the precise and necessary pressure, known as torque. Its value is measured in newtons/meter (NM).

Once you enter the value, you can tighten the screw in question. When you reach the prescribed pressure, you will see that the torque wrench gives you two signals: one sensitive, with a kind of crack, and the other auditory, with a click. If it is digital, it can also make a digital sound signal.

The point is that, at that point, the torque wrench has just told you that the pressure is correct. It is not advisable to tighten more. Also, do not untighten screws with it.

Something as simple as a bad tightening can lead to problems, discomfort, or damage to your bike or mountain bike. That’s why a torque wrench can provide a precise and professional fit for your motorcycle.

How to Use a Torque Wrench

One of the tools needed by the auto mechanic at home is a torque wrench. If you want to follow all the manufacturer’s recommendations for routine repairs and services, you need to know how tight to tighten screws.

The torque wrench will tell you exactly how tight something is and allows you to set the wrench so that you don’t tighten a screw or nut. Remember to leave the setting to the minimum when you finish after using this tool so that the internal spring won’t deform, and it will continue to work flawlessly for so many years.

And treat it with care, prevent it from receiving strong blows, falling to the ground, or it will become out of calibration, and it is not exactly a cheap tool. For the world of bicycles, we do not need tightening torques greater than 50 Nm.

So, it is not recommended that the graduation of our dynamometer widely exceed that figure, or we will not have precision with low values.

Action and Use

The torque multiplier is a device that allows a given torque to be applied by the action and use of a planetary gear train of one or more stages. Each stage increases the torque applied by the factor corresponding to the transmission ratio, considering the multiplier set’s degree of efficiency.

Through a torque wrench, the operator manually applies a known torque at the input of the multiplier. By the action of the gear ratio of the multiplier, the output torque is the one corresponding to the torque applied by the operator, multiplied by the factor, already considering the degree efficiency.

  • Accuracy better than +/- 5%, just apply the factor to result in the output torque.
  • Designed and built with bearings, ensuring repeatability and long life.
  • Ideal for applying a certain torque, using snap torque wrenches, analog or digital torque wrenches, or to facilitate the disassembly of high torque screws.
  • Own, for use in the petrochemical industry, power generation, mining, conveyors, and large machinery.
  • Compact design that allows application in restricted locations.
  • Supplied with standard reaction bar, other bars can be made available on request;

Types of Torque Wrenches

The torque wrench works most of your time as a normal wrench. Only when the previously defined torque wrench is reached is the wrench mechanism activated.

At that point, the wrench should not be turned more than the torque that has been set. There are many types of torque wrenches on the market with different operating mechanisms.

Limit (Click) Key

One of the most well-known is called the limit (click) key. This type of wrench is equipped with a particular click latch (with clutch), that prevents the torque wrench from continuing to turn after reaching the set torque.

Its operation resembles a ratchet wrench, that rotates only one way. The wrench will click in the same way when the specified torque is surpassed.

Digital Type

If you want efficiency and convenience, we recommend buying a digital torque wrench. When you will reach your target, it will beep, light, or vibrate.

Slip Type

It comes with a simple yet effective design. It loses grips when the targeted torque is reached. Unfortunately, you cannot completely rely on this type of wrench as it handles rarely more than 100 Nm.

Hook Wrenches

There are also other types of torque wrenches are available such as hook wrenches. The system of these keys means that the greater part of the tool opens approximately 20 degrees after reaching the defined torque, indicating that the adjusted torque has been reached.

Best Brands of Torque Wrenches

Campbell: Campbell is one of the leading brands of torque wrenches. They design a versatile tool that is capable of the garage jobs to the job site.

DeWalt: DeWalt wrench is great for those who want convenience and mobility. Powered by 20V cordless batteries and weighing just 3 kg, it is ideal for homework or to meet emergencies in outdoor locations, such as changing a car tire.

DEWALT Torque Wrench, 3/8 inch Drive, Micro Adjust (DWMT75463)
  • Torque wrench comes with a protective head bumper
  • 3/8 torque wrench has a locking trigger
  • 3/8 torque wrench comes with bi-material grip
  • ASME/ISO/TAA Compliant
  • Heavy Duty Storage Case
DEWALT Torque Wrench, Micro Adjust, 1/2" Drive (DWMT75462)
  • Torque wrench comes with a protective head bumper
  • Torque wrench 1/2 inch drive has a locking trigger
  • 1/2 torque wrench comes with bi-material grip
  • ASME/ISO/TAA Compliant
  • Heavy Duty Storage Case

The machine still has good torque and a speed of up to 1,500 RPM. In addition, DeWalt is a highly regarded brand in the market, has great customer service and an extensive network of spare parts.

Stanley: This Stanley’s impact wrench is a real machine. It has a double hammer mechanism, 3/4 “socket, speed: 4,500 RPM, and an engine that uses 6 blades, being able to slow down the part more quickly.

In addition, the wrench uses 90 psi air compression, sealed bearings for longer life, variable speed trigger for better control, excellent ergonomics, and aluminum housing. It is ideal for professionals who work with high torque nuts: automotive mechanics, tire repairers, metal structure assemblers, and more.

Stanley Proto J6014C 1/2" Drive Ratcheting Head Micrometer Torque Wrench
  • Calibrated to +/- 3% clockwise direction and +/- 6% counter clockwise at 20% to 100% of full scale
  • Calibration is accomplished by manual loading the torque wrenches
  • Manufactured to meet standard industrial torque applications, general industry, heavy equipment, and maintenance
  • Made in USA
Proto Stanley J6168F 1/4" Drive Dial Torque Wrench, 6-30" Pound
  • 6-30 in-lbs. thru 120-600 in-lbs./7-35 cm kg thru 140-700 cm kg
  • Accurate to 4% of torque reading in both directions at 20% to 100% of full scale
  • Industrial all steel or aluminum torque transfer components
  • High alloy torsion drive design - accuracy not effected by hand position
  • Dual scale (English/Metric) with clockwise and counterclockwise operation - fewer wrenches needed to complete job, Made in USA


If you are one of those who enjoy car mechanics jobs; the torque wrench is an essential tool to achieve certain precision. On the other hand, while taking a look at your car’s workshop manual; you will see that each screw has a specific tightening torque that must be respected.

Torque wrenches are a very useful tool for DIY projects, repairs, and industrial maintenance to ensure users’ safety. Since there are different types of torque wrenches are available, it is advisable to know about all types.

If you are going to do auto mechanic work sporadically, you would better get two different wrenches to cover a wide enough Nm range. Even so, your investment will be much less than if you buy a professional key. Also, unless you do work that requires a lot of precision, the keys’ percentage of error is sufficient.