Curious about how clutches work and how they can help your bike's performance? In this article, we dive into the mechanics of a clutch system and how changing and upgrading different components can improve performance and your riding experience.
Owning and operating a motorcycle of any kind involves great levels of fun, but also requires a keen eye on maintenance along with unlimited options to modify the machine and its working parts. One key element at the heart of the engine is the clutch system, which is more important than just transferring power for a multitude of reasons. Aside from its core job of applying the power to the driveline, the clutch in any kind of motorcycle can change the entire characteristics of the machine and also the rider’s experience. Have you been maximizing your time on two wheels? Let’s discuss why clutch performance should be at the top of your thought list before your next ride.
The clutch is the bike's key component in regulating the engine's power to the rear tire - Dean Wilson - Courtesy of Rockstar Energy Husqvarna Factory Racing, Simon Cudby
Clutch Connection Explained
At its most basic function, the clutch is the backbone of power delivery from a motorcycle’s crankshaft to the transmission. With all of this mechanical responsibility comes the importance of the system’s internal components and wear condition. After all, the connection from the rider to the machine’s characteristics and performance relies heavily on clutch components. From the street to the dirt, things like stall control, traction, momentum, power transfer, and more can be improved and controlled with the many optional components available. But how does it work?
Starting with the pull of the clutch lever, a sequence of events occur that transfers the power of the engine to the driveline, the final stop being the rear tire. Whether a cable or hydraulic system, the clutch springs are the first action to relieving or applying pressure to the friction plates within the basket, mediating the crankshaft output to the transmission system and driveline through the inner hub, pressure plate, and clutch basket. When the lever is pulled, the pressure is relieved inside and friction disks are not engaged. As the lever releases, the clutch goes to work through the action of the pressure plate engagement to the clutch pack, increasing friction between the friction discs and plates, thus turning the center hub and applying the transfer of torque to the transmission. It then travels through the gears, to the countershaft, through the chain and sprockets, and finally the rear wheel and tire. As anything goes, wear condition and type of components within are integral to feel and performance. When it’s time to work on or maintain your motorcycle’s clutch, selecting which clutch replacement level or system you’ll be choosing is a decision that hinges on rider needs and expectations.
Learn more about how a clutch works here:
From friction plates to complete clutch assemblies, the value of each component can be found in different forms. The friction discs and drive plates are the most important working contact friction points of engagement, while the options of different spring rates and system combinations can dictate how the transfer of power is modulated. Beyond the clutch packs, components like clutch baskets, hubs, pressure plates, and basket sleeves can all provide added characteristics of oil cooling, wear prevention, power modulation, and options to suit your tastes and needs.
All the parts of the clutch work together to allow the rider to regulate power delivery to the rear wheel.
Breaking down some benefits of a properly operating clutch system comes down to clutch feel, power engagement, and added torque and traction. Riders that have their clutch in top operating condition will feel no slip or loss of power when a load is placed on the system, enjoy a lever feel that is modular and consistent with the engagement of the plates, and enjoy the benefits of efficient power transfer to the rear wheel. Added benefits of oil cooling/circulation within upgraded systems can also affect the clutch’s lifespan, durability, and engine temperature as well. Of course, normal maintenance like oil changes, cable adjustments, and plate inspections are key to the longevity of the system. Choosing different parts when servicing will create the various benefits the rider is looking for.
Rekluse's billet components work together to move more oil through the clutch, increasing durability and decreasing operating temperatures.
Rekluse Products and Your Manual Clutch System
For those who prefer the standard manual clutch, depending on your preference, performance, and demand, Rekluse has multiple options. Core Manual components, TorqDrive Clutch Packs, and Core Manual TorqDrive combination can provide varying levels of performance with different characteristics to suit the rider’s needs.
At the most basic level, a clutch pack replacement into your stock system will breathe new life into your motorcycle. By introducing more friction plates into Rekluse’s world-renowned TorqDrive Clutch Packs they're able to vastly improve performance characteristics and add up to 25% torque increases overstock, giving the rider more drive and acceleration. In most applications, Rekluse’s basket sleeves will fit into the stock clutch basket, aiding in its lifespan and keep modulation smooth, all while keeping the stock clutch cover. The addition of Core Manual components introduces billet construction to the inner hub, pressure plate, and lighter overall weight, giving the system superior durability and lifespan and improving oil flow within the system. The extra friction disks result in more torque at the rear wheel, while the overall weight reduction and increased oil flow offer benefits like longer lifespan and improved clutch feel.
TorqDrive Clutch Pack delivers a high-performance manual clutch within an OEM clutch footprint
Combining it all together in Rekluse’s flagship manual clutch system, the Core Manual TorqDrive kit is used by top factory race teams worldwide and was the clutch of choice for recent champions like, Aaron Plessinger (2018 250 West SX/MX Champion), and Dylan Ferrandis (2019 250 SX Champion). Options like spring rate changes add to the tunability of the system, offering a stock feel or lighter-than-stock feel, depending on the rider’s demands. As mentioned prior, connection to power, added torque, better oil cooling capability, and the confidence that comes with a quality product are all added benefits of these systems. While a manual configuration is what many riders are used to, the option of making your motorcycle clutch system automatic is an entire other option to change ride characteristics, power delivery, and more, and has even been trusted at the highest level by the Monster Energy / Yamalube / Star Racing Yamaha race team over the 2019 season. Dylan Ferrandis’ 1-1 finish with Rekluse’s RadiusCX clutch at Redbud was the highest testament to automatic clutch performance.
Core Manual TorqDrive is Rekluse's premier manual clutch, combining their Core and TorqDrive technologies into one package.
Automatic Clutch Options
For riders that want to go the route of an automatic clutch configuration, there are many (sometimes surprising) benefits to it. The ability to stall your motorcycle is eliminated by Rekluse’s proprietary EXP technology, and centrifugal force automatically engages and disengages the clutch pack based on RPM. Beyond this, advanced riders can see benefits like increased momentum in corners and still use the clutch lever just like they always have.
The EXP disk is the part that gives an auto clutch its automatic functionality.
Beginners and advanced riders alike often find that less clutch usage can add to the ease of riding and reduce overall fatigue. With optional spring and wedge options available, tunability and power delivery characteristics of this EXP system are open to rider preferences. The clutch lever still functions as it always did, and this system can connect the rider to the experience longer via less mental and physical taxation. The benefit? Longer, care-free rides equaling happier riders.
Rekluse offers three different options of auto clutch packages, each with varying levels of performance and modification. Beginning with the RadiusX system, this product offering utilizes the stock basket, hub, and pressure plate, but adds Rekluse’s EXP auto clutch disk and TorqDrive friction disks, resulting in high-performance characteristics and an auto clutch configuration. Adding Core technology into the mix, the Core EXP 3.0 package includes Rekluse’s billet core, their EXP auto clutch, and utilizes your stock friction disks. Culminating everything into the highest performance auto clutch set up on the market, Rekluse’s RadiusCX system combines Core, EXP, and TorqDrive technology into a race-ready configuration that offers all of the aforementioned benefits of the added oil cooling and reduced weight and a level of auto clutch that has never been matched.
Star Racing Yamaha utilised RadiusCX throughout the 2019 Lucas Oil Pro Motocross season. Hear from the rider and the team why they chose to run auto clutches:
Engine/Clutch Life and Heat
With any level of off-road motorcycle, the demands of riding at various skill levels and conditions can lead to stress and strain on the machine as a whole over time. Naturally, the friction-based transfer of power inside of the clutch system is a source of engine heat. Heat is a large factor in clutch fade and wear, and clutch fade is power loss and slippage from the crankshaft to the transmission due to excess heat in the clutch. The opportunity to lower operating oil temperatures can improve the performance and also add to the lifespan of both the clutch system and overall engine package.
Rekluse Core technology is designed to optimise oil flow through the clutch
With the added benefits of both the TorqDrive friction disks and billet internal components, operating temperatures are lowered while oil circulation is improved by design and function. Physical wear is prolonged with these billet machined pieces and all the aforementioned traits of the motorcycle’s characteristics are affected by heat and directly transfer over to the rider, so keep it cool and your motorcycle will thank you!
As any passionate rider does, keeping your dirt bike in peak operating performance is the best way to provide the best experience. Whether you’re a racer, a weekend warrior, trail rider, or a few and far between enthusiast, doing your research and investing into your clutch system is one of the most noticeable and valuable things a rider can do. Understanding the way everything works is important.
Written by Mike Emery at Rekluse USA.