Why Racetorx Developed a Right-Hand Thumb Brake | Racetorx Tech

A right-hand thumb brake can provide an essential alternative when a motorcycle’s conventional control layout does not match the rider’s physical needs. Motorcycles are traditionally arranged around the assumption that every rider can operate the clutch with the left hand and the rear brake with the right foot. For some riders, an amputation, missing fingers, a fused wrist, restricted joint movement or reduced use of a foot can make those controls difficult or impossible to operate.

The Racetorx right-hand thumb brake was created in response to requests from riders who needed another option. Rather than treating accessibility as an afterthought, Racetorx took the proven principle of its original thumb brake and developed a reversed, mirrored version for the right-hand side. The result is the RTX730 right-hand thumb brake: an adjustable hydraulic control designed to help riders place rear-brake operation where they can use it.

In this article, we explain why the RTX730 was developed, how the system works, who it may help and how the same engineering could support future right-hand clutch and throttle solutions.

Why was a right-hand thumb brake needed?

The original Racetorx thumb brake was designed for the left-hand side. That arrangement works for many road and track riders, but customer conversations revealed a group for whom a left-hand control was not practical.

Some riders had limited or no use of their left arm. Others had a fused left wrist, missing fingers or another restriction that prevented them from comfortably operating a conventional left-hand control. In other cases, limited movement in a foot meant that the usual rear-brake pedal was not a workable option. Where both issues were present, moving the rear-brake control to the right hand could provide a practical route back to operating the motorcycle.

Racetorx founder Dale developed the right-hand thumb brake by reversing the architecture of the existing design. It was not created simply to add another product to the range. It came from a clear functional problem raised by real riders.

An accessibility-led motorcycle control

Motorcycle adaptations are personal because no two riders have exactly the same movement, strength or reach. A useful control therefore needs more than a different mounting side; it must also offer enough adjustment to be positioned around the individual.

The RTX730 provides four points of movement, allowing the mechanism and thumb paddle to be adjusted to suit the rider’s reach and preferred hand position. Two optional knurled thumb paddles provide further choice, helping the rider find a contact point that feels secure and natural.

For someone who cannot use a conventional rear foot brake or a left-hand thumb brake, this adjustability can be fundamental. The right-hand thumb brake places hydraulic braking control within reach of the right thumb, giving the rider an alternative way to operate the rear brake.

That does not mean one configuration will suit every motorcycle or every disability. It means the rider and fitter have a more adaptable starting point from which to create a suitable control layout.

How does the RTX730 right-hand thumb brake work?

The RTX730 is a hydraulic thumb-brake mechanism for standard 22mm handlebars. Pressing the thumb paddle operates the Brembo master cylinder, converting the rider’s input into hydraulic pressure for the braking system.

The kit can be configured to connect directly to the rear brake calliper or to work in conjunction with the existing rear foot master cylinder, depending on the motorcycle and the required setup. A Racetorx GP-inspired reservoir tube and black cap are included.

The mechanism is machined from T6 billet aluminium and anodised black. Its pivot pins and pushrods are manufactured from Ti 6Al-4V titanium. A detent-ball thumbscrew supports precise adjustment, while the knurled paddle surface provides a positive contact point for the rider’s thumb.

These are performance-grade details, but their value is not limited to racing. In an accessibility-led application, accurate positioning, consistent operation and a secure contact point are equally important.

Choosing the correct master cylinder and fitment

The right-hand thumb brake is available with a choice of Brembo master cylinder. The 11mm option is intended for single-cylinder motorcycles from 125cc to 500cc, including supermoto, motocross, trials and road applications. The 13mm option is intended for two-, three- and four-cylinder motorcycles from 500cc to 1400cc, covering road, track, superbike and adventure applications.

Although the kit is designed as a universal solution for the majority of motorcycles, universal does not mean that every installation is identical. Handlebar-equipped motorcycles generally provide more space. Bikes using clip-ons can present clearance challenges around fairings, tanks and frames, particularly at full steering lock.

Before ordering, check the handlebar, paddle, master-cylinder and hydraulic-routing requirements for the specific bike and rider. Racetorx also offers a workshop fitting service in Peterborough for customers who want the system professionally installed.

Could the right-hand system also operate a clutch?

The reason for moving a rear-brake control can apply just as strongly to a clutch. A rider with restricted use of the left hand may be unable to operate a standard clutch lever, even if the throttle and front brake remain accessible on the right.

Racetorx is testing the potential for the right-hand architecture to support hydraulic clutch operation. The aim would be to give riders another route to bringing essential controls onto the side they can use effectively.

This clutch application is a development project and is not a current function of the RTX730 brake kit. Any future system would require the correct hydraulic design, compatibility checks and testing before release.

The next development: a high-performance right-hand thumb throttle

Dale is also exploring how the same adjustable mechanism could form the basis of a high-performance thumb throttle. In this version, the hydraulic master cylinder would be removed and replaced by a throttle-control mechanism.

The principle will be familiar to anyone who has ridden a quad bike, where throttle input is commonly controlled by the thumb rather than by rotating the grip. The Racetorx concept would take that familiar input and combine it with the adjustability and engineered construction of the thumb-brake platform.

Both cable-operated and fly-by-wire throttle systems are being considered. The objective is to give riders who struggle with a conventional twist grip a precise, adjustable right-hand alternative. This is a future development rather than a feature included with the RTX730 currently on sale, and further design and testing will determine the final specification.

Who should consider a right-hand thumb brake?

The RTX730 may be relevant to riders who:

• cannot comfortably operate a conventional rear-brake pedal;
• have limited or no use of the left hand or arm;
• cannot use a left-hand thumb-brake arrangement;
• need key motorcycle controls positioned on the right-hand side; or
• want a highly adjustable right-hand rear-brake control for a specialist build.

The correct solution depends on the rider, motorcycle and complete control layout. A specialist fitter should assess the installation, hydraulic routing, clearances and rider reach before the motorcycle is used.

Engineering that keeps riders riding

The right-hand thumb brake began with a simple question from customers: what happens when the conventional control layout does not match the rider?

Racetorx answered by adapting an established design rather than expecting the rider to adapt around an unsuitable system. The RTX730 mirrors the original thumb brake, retains extensive adjustment and moves rear-brake operation to the right hand for riders who need it there.

It is a specialist component with a clear purpose. More importantly, it demonstrates how rider feedback and performance engineering can come together to remove barriers and help more people continue riding.