Learn and Earn From Roller Brake Testers

If you run an MOT centre or independent garage, and particularly if you run an MOT Bay, then you know how important it is to ensure that vehicles are operating safely and efficiently. One crucial aspect of vehicle maintenance is the brakes, which are responsible for slowing down and stopping the vehicle.

A Roller Brake Tester (often known as an MOT Brake Tester) is one of the most important pieces of equipment in many UK MOT facilities. It provides a controlled way to measure braking performance and is a key part of the equipment used in many MOT test bays.

But what exactly does a roller brake tester do, what should you look for when choosing one, and how can a brake tester contribute to a profitable MOT operation?

In this article, we’ll take a closer look at Roller Brake Testers, including how they work, the benefits they provide, and some common questions and concerns about their use. So whether you’re a seasoned mechanic or just learning about these devices, we hope you find this article informative and helpful.

What is a Roller Brake Tester?

A Roller Brake Tester (RBT) is a machine designed to measure the braking forces produced at a vehicle’s wheels. Rather than testing a vehicle’s brakes while it is travelling along the road, the vehicle is positioned on powered rollers.

The rollers turn the vehicle’s wheels while the tester applies the brakes. Sensors measure the braking force produced at each wheel and the results can then be assessed against the applicable testing requirements. This gives an MOT tester a controlled and repeatable way of assessing braking performance.

Roller Brake Testers are widely used in UK MOT facilities because they can provide measurements for individual wheels and axles, helping identify issues such as inadequate braking force or significant differences between wheels.

For an MOT station, the brake tester is therefore an important part of the overall testing process rather than simply another piece of workshop equipment.

How Do You Use a Roller Brake Tester?

Although modern Roller Brake Testers can incorporate sophisticated electronics and software, the principle is relatively straightforward.

The vehicle is driven onto the rollers, ensuring the wheels are centred on the two sets of rollers. The rollers rotate the wheels until the vehicle is correctly aligned and, as the brakes are applied, the machine measures the force required to slow the wheels.

The brake is gradually applied and released while the tester observes the braking effort and checks for excessive fluctuations. The brake is then applied again until maximum effort is achieved or the wheel locks.

The equipment can measure braking force at the individual wheels and provide the tester with readings that can be used to assess the vehicle’s braking performance and determine if it meets the necessary safety standards.

Truck Roller Brake Testers work by having a truck drive onto a set of ceramic-coated rollers, which produce friction. These are linked up to the testing system, and the brakes can be tested by keeping the vehicle static while turning the wheels at a consistent speed.

If there is a parking brake on the axle you are testing, you would test that next, but if there isn’t, move the vehicle to test the next axle. The service brake test for the front wheels and rear wheels uses the same procedure and Reasons for Rejection (RfR), so the instructions apply to both axles.

If the vehicle or system cannot be tested on a Roller Brake Tester, set up the decelerometer in the vehicle in accordance with the equipment manufacturer’s instructions.

Modern systems can also incorporate features such as:

• Automatic vehicle detection
• Axle and wheel-weight measurement
• Digital displays
• Automatic calculation of results
• Slip detection
• Integrated MOT testing software
• Printer and data-recording functions
• Remote controls or handheld controls on some systems

The exact features vary between manufacturers and models, so it is important to choose equipment appropriate for the vehicles and MOT classes you intend to test.

Why Are Roller Brake Testers Important For an MOT Bay?

Brakes are one of the most important safety systems on any road vehicle. An effective testing system allows braking performance to be assessed in a controlled environment rather than relying solely on visual inspection.

For an MOT centre, a suitable RBT can also help make the test process more consistent and efficient.

The RBT must be on DVSA’s latest list of acceptable equipment and, where applicable, approved for the MOT class and type of test lane in which it will be used. The equipment used by an MOT station must meet the requirements for the vehicle classes being tested and must be maintained and calibrated correctly.

That means choosing a brake tester isn’t simply about buying the largest or most advanced machine available. The equipment needs to be suitable for the proposed MOT classes, the premises and the way the test bay will operate.

Types of Brake Tester

A roller brake tester isn’t the only way of assessing braking performance.

Depending on the vehicle and circumstances, MOT testing can involve different types of brake testing equipment.

Roller Brake Testers

Roller Brake Testers are often embedded into the ground so that they sit at the same level as the floor, using powered rollers to rotate the vehicle’s wheels while measuring braking force. They are equipped with rollers that rotate as the vehicle’s wheels roll on them, allowing for a more realistic simulation of driving and braking conditions.

They are particularly useful for fixed MOT testing facilities because the equipment can be installed into a dedicated test lane and used repeatedly throughout the working day.

Plate Brake Testers

Plate brake testers use moving plates rather than rollers. As the vehicle brakes, movement of the plates is measured to determine braking performance. They can be suitable for certain applications where a roller system isn’t appropriate.

Decelerometers

A decelerometer is a handheld electronic device that measures vehicle deceleration during a road test. DVSA recognises approved decelerometers for MOT testing, with different categories covering different vehicle classes.

A decelerometer can be useful where the vehicle cannot be tested on a plate brake tester or roller brake tester. The current MOT inspection guidance also contains specific instructions for vehicles whose drive configuration, transmission or braking system makes a conventional brake test unsuitable.

The Advantages of Roller Brake Testers

A key advantage of Roller Brake Testers is their ability to test the braking performance of a wide range of vehicles, from small cars, vans and light commercial vehicles, to larger trucks and buses.

Many smaller Class 1 Roller Brake Testers are also widely used for motorcycle brake testing, where they meet DVSA requirements.

Roller Brake Testers are often placed just in front of the 4 post MOT ATL lift, ready to be used for the rest of the MOT test.

The Disadvantages of Roller Brake Testers

Often, Roller Brake Testers are very heavy and sit in a cartridge unit that needs to be embedded into the ground, so that it sits at floor level within the garage or MOT Bay.

This means that as part of the installation, the floor needs to be cut out and concreted to make a suitable area for the RBT to be placed and securely fastened into before it can be operated. Therefore, the cost of the civil works and the potential electrical upgrades must be factored into the purchase price of the Roller Brake Tester.

How Are Brakes Tested on an MOT?

Initially after checking the use of the brake pedal for wear or excessive play, a visual inspection of the brake pads, brake disks and braking system, looking for visible wear or leakages must be done.

Next, the efficiency and braking balance will be checked on a Roller Brake Tester (RBT). The primary brake tester should normally be used, however some vehicles may be unsuitable for an RBT because of their drive configuration, transmission type or braking system. For some 4WD vehicles, for example, the manufacturer may specify a decelerometer test for service-brake performance. The tester should follow the current DVSA procedure and any relevant manufacturer instructions.

The braking performance numbers must be reported to DVSA as part of the MOT test. For applicable connected MOT equipment, brake-test results are transferred to the MOT Testing Service (MTS) and recorded against the MOT being carried out.

What Are the Benefits of a Roller Brake Tester?

1. Accurate Measurement

A Roller Brake Tester provides numerical measurements of braking force rather than relying solely on visual assessment, which can help the tester identify differences in braking performance that may not be obvious during a visual inspection.

2. Repeatable Testing

Because the vehicle is tested under controlled conditions, the process can be repeated consistently. This is particularly valuable for an MOT centre where the same equipment may be used many times every day.

3. Efficient MOT Testing

When correctly integrated into an MOT bay, the brake tester can form part of a logical testing sequence alongside other equipment such as a vehicle lift, headlight tester and emissions equipment. A well-designed bay can therefore reduce unnecessary vehicle movement and help the tester work efficiently.

4. Suitable for a Wide Range of Vehicles

Different Roller Brake Testers are designed for different vehicle classes and applications. Before purchasing equipment, however, you should check the approved specifications of the individual machine and make sure it is suitable for the classes of vehicle your MOT centre intends to test.

5. Additional Workshop Opportunities

A brake test can also provide useful information when carrying out servicing, inspections or brake-related repairs. For example, if braking performance is uneven, the results may indicate that further investigation is required.

The important point is that a brake tester should be viewed as part of the wider workshop operation rather than solely as a machine used to obtain an MOT pass or fail result.

Can You Fail the MOT for Brakes?

Yes, there are a range of tests that need to be carried out and can fail the MOT, these include:

• Brake condition and operation
• Service brake performance and efficiency
• Secondary brake performance and efficiency
• Parking brake performance and efficiency
• Additional braking device (retarder) performance
• Anti-lock braking system (ABS)
• Electronic braking system (EBS)
• Brake fluid contamination

For full details see the latest guidance on the DVSA website:
https://www.gov.uk/guidance/mot-inspection-manual-for-private-passenger-and-light-commercial-vehicles/1-brakes

At What Speed is the Brake Test Carried Out?

Speed using a Roller Brake Tester (RBT):
Unlike a road test, the vehicle is not driven at a set road speed during an RBT test. The brake tester’s rollers rotate the vehicle’s wheels, and the tester follows the equipment’s operating procedure to measure braking effort.

Note: The roller brake tester sets the speed of the test as the rollers themselves are spinning and the vehicle is simply braking

Speed using a plate brake tester:
For each brake check, the mechanic must drive the vehicle forwards at a steady speed of about 4mph up to the plate tester.

Speed using a decelerometer:
Drive the vehicle on a level road at a steady speed of approximately 20mph (32kph) and progressively apply the service brake to maximum

What is the Minimum Brake Performance for MOT?

If braking effort from any wheel of the vehicle is less than 70% of the maximum effort recorded from the other wheel on the same axle, or in the case of testing on the road, if the vehicle deviates excessively from a straight line, then this is a major MOT Failure.

If the braking effort from any wheel is less than 50% of the maximum effort recorded from the other wheel on a steered axle then this is deemed dangerous.

For full up-to-date MOT brake guidance from DVLA see: https://www.gov.uk/guidance/mot-inspection-manual-for-private-passenger-and-light-commercial-vehicles/1-brakes

What is the Minimum Brake Efficiency for MOT?

For M1 passenger vehicles with a service brake operating on at least four wheels, the minimum service brake efficiency is 50% for vehicles first used before 1 September 2010 and 58% for vehicles first used on or after 1 September 2010. Other vehicle classes have different requirements.

The normal requirement for parking brakes (hand brake) is 16%, with 50% being the dangerous-defect threshold.

For full up to date MOT brake guidance from DVLA see:
https://www.gov.uk/guidance/mot-inspection-manual-for-private-passenger-and-light-commercial-vehicles/1-brakes

Are Brake Pads Checked as Part of an MOT Test?

Yes, the brake pads are checked as part of the annual MOT test, as well as the brake linings, fluids, braking efficiency and the entire braking system. As this is the only means of efficiently stopping a vehicle at speed, it is one of the most important MOT tests to be completed.

What is the Brake Pad Limit for MOT?

For MOT if a brake pad is worn down to the wear indicator or if the brake lining or pad is contaminated with oil, grease etc, then this is a major MOT failure. If the pad is below 1.5mm, or the pad is missing or incorrectly mounted, this is deemed as dangerous.

What is the Calibration Interval of the Roller Brake Tester?

RBTs, PBTs, ATL and motorcycle weighing facilities, and headlamp beam testers can be calibrated anytime during the six months following their last date of calibration. DVSA requires calibration records to be readily retrievable and kept for at least two years.

Since April 2023, calibration must be carried out by the manufacturer, a company that has taken over manufacturer support, or a calibration specialist; VTS staff cannot carry out this calibration.

For the latest DVSA guidance see:
https://www.gov.uk/guidance/mot-testing-guide/appendix-2-facilities-and-security

Can a Roller Brake Tester Make an MOT Garage Money?

Potentially, yes – but the value of an RBT shouldn’t be measured simply by looking at the price charged for an individual brake test. For an MOT centre, the greater opportunity comes from having the equipment required to operate an efficient testing facility.

An MOT bay can generate revenue through the tests themselves while also creating opportunities to identify legitimate repair and maintenance work. A vehicle that requires further investigation following an MOT can potentially return to the workshop for repairs, servicing or additional inspection.

However, garages should avoid viewing the MOT test as a sales exercise. The tester’s responsibility is to carry out the test according to the applicable DVSA requirements and record the result accurately.

The commercial benefit comes from operating an efficient, compliant workshop and providing customers with necessary repair and maintenance services, not from creating work unnecessarily.

Choosing the Right Brake Tester For Your MOT Bay

Buying an RBT is a significant investment, so it is worth considering the complete installation rather than looking at the machine in isolation.

Vehicle Classes

Start by establishing which MOT classes you intend to test. Different vehicle classes have different equipment requirements and the RBT must be appropriate for the vehicles being tested.

DVSA publishes approved equipment information for MOT stations, so check the current requirements before committing to a machine.

Available Space

The dimensions and layout of your MOT bay need to accommodate the equipment and the vehicles being tested.

DVSA’s MOT testing guidance sets requirements for the installation and layout of RBTs, including requirements relating to the floor and positioning of the equipment. This is particularly important if you’re converting an existing workshop into an MOT facility.

Installation and Civil Works

Many in-ground Roller Brake Testers require preparation of the workshop floor.

Depending on the existing building, installation may involve excavation, concrete work, electrical work and installation of the tester itself. These costs should be included in the project budget from the beginning.

A supplier experienced in complete MOT bay installations should be able to advise on the required preparation before work starts.

Calibration and Maintenance

Calibration isn’t something to overlook after installation.

DVSA guidance states that RBTs and plate brake testers must be calibrated by the original manufacturer, a company that has taken over equipment support from the manufacturer, or a calibration specialist. Calibration certificates must contain specified information, including the test load, gauge readings and percentage error, and records must also be readily retrievable and retained for at least two years.

Regular maintenance is equally important. Keeping the rollers, sensors, electronics and associated components in good condition helps ensure the equipment continues to perform reliably.

What Has Changed in MOT Equipment Requirements?

MOT equipment requirements are not static, which is why garages should always check the latest DVSA guidance rather than relying on information published several years ago.

For example, DVSA introduced changes to Class 4 MOT bay jacking equipment from 1 April 2026. The new specifications apply to applications to open or change an MOT centre from that date onwards; existing approved Class 4 bays do not need to change simply because of the new requirements if the centre isn’t being changed.

This is a good example of why an MOT bay project should be planned around the current requirements rather than an old equipment checklist.

Getting More From Your MOT Bay

A profitable MOT operation is about more than buying individual pieces of equipment. The best results come from designing the complete bay around the workflow of the tester.

Consider:

• Which MOT classes you want to cover
• The vehicles you expect to test
• Available workshop space
• The position of the roller brake tester
• Vehicle lifts and jacking equipment
• Headlamp testing
• Emissions testing
• Wheel-play testing
• IT and MOT testing equipment
• Calibration and servicing
• Future expansion
• Installation and electrical requirements

Thinking about the complete system before installation can prevent expensive changes later.

Investing in the Right Roller Brake Tester

For an MOT centre, a Roller Brake Tester is much more than a machine for checking brakes.

It is a core part of the MOT testing process and, when combined with the right equipment and a well-designed MOT bay, can help a garage operate efficiently while providing a valuable additional service to customers.

The key is choosing equipment that is appropriate for your vehicle classes, premises and expected workload, and making sure installation, calibration and ongoing maintenance are included in the plan.

If you’re planning a new MOT facility or upgrading an existing bay, getting advice before purchasing the equipment can help you avoid costly mistakes and ensure that the finished installation works for your garage in the long term.

At Concept Garage Equipment we can offer advice or supply Roller Brake Testers, including delivery, installation and staff training in the correct use of the brake testing equipment or any other garage equipment up to a full MOT Bay.

Looking for a Roller Brake Tester for your MOT bay? Call the friendly team at Concept Garage Equipment on 01302 203 888 or use the contact form to get in touch.

 

 

Note: All information is accurate at the time of writing, September 2026.