What You Need to Know About Master and Slave Cylinders

Motorbike brake systems are mightily impressive. They can bring a racing bike to a standstill in just a few seconds and do so all by simply pressing a lever. But to make this happen, there are vital components hard at work.

Understanding the mechanics behind motorbike brake systems is something every rider should become familiar with. This helps to ensure each aspect of the system is functioning correctly. Faulty brakes or inefficiencies within the braking mechanisms could pose serious threats to a rider, so taking the time to keep all of the parts of the brake system working in tip top condition is a must.  

In this article, we delve into master and slave cylinders in particular, and the role they play in motorbike brake systems and what you need to know about them.

For help changing cylinders or optimising your bike’s performance, don’t hesitate to get in touch with our expert team here at Venhill. Similarly, you can browse our online shop for the very best in cables, hoses, hydraulic components and tools.

What are the Master and Slave Cylinders?

The master cylinder is basically a piston that pushes brake fluid into the slave cylinder (the caliper). This forces the brake pad to press against the brake disc, stopping the vehicle.

The size of the cylinders should be appropriate for the size of the motorbike and purpose. Larger cylinders will require more force, whereas a smaller one will require less force. Cylinders that are uneven in relation to the bike may also impact overall performance. This is worth noting in case you buy a second hand bike, whereby a previous owner may have replaced the master or slave cylinders. If you are replacing the master or slave cylinders, always refer to the manufacturer recommendations.

Getting the Most out of Master and Slave Cylinders

Brake Fluid

Brake fluid can degrade over time and need replacing to maintain a high functioning brake system. If not, it could damage the master and slave cylinders.

Your bike manufacturer can recommend what DOT to use (usually DOT 4). Our recent article discussed how brake bleed kits work which discussed that brake fluid is usually changed at least every 2 years. Over time, brake fluid absorbs water and performance is compromised. Although you may not feel lower performance under normal circumstances, it is when you brake suddenly (i.e. in an emergency), when this lower braking performance is felt.

Cylinder Maintenance

Cylinders can often last the test of time and there isn’t too much that riders need to do to maintain a healthy performing cylinder.

Brake fluid is likely to have the biggest impact. Old, low quality brake fluid may contribute to corrosion of the cylinder. This is why it’s recommended to change brake fluid every 2 years to ensure the fluid doesn’t damage these other parts of the bike.

Brake Lines

For the brakes to work effectively, force must be transferred from the master cylinder to the calipers. This travels via the brake lines. If the brake lines expand, or leak, the brakes won’t function to their optimal performance. This could result in the brakes feeling spongey and a bit slow, or at the extreme, not working at all.

Needless to say, brake lines therefore play a vital role in the overall braking system and the overall performance of the master and slave cylinders.

Braided brake lines offer a better solution to cheaper rubber lines, as they reduce potential bulging or expansion which compromises stopping performance.

Featured Products

Check out some related products from Venhill below:

Frando Clutch Master Cylinder

This 17mm piston sized clutch master cylinder is forged with aluminum alloy. It has a black body and black short lever with reach adjustment. The kit is packed with everything you need, including; an interlock switch, banjo bolt, reservoir pot with clamp and a mirror mounting bracket.

It can be used with 11nb-3-14 clutch slave cylinder for conversion from cable operation. It is suitable for use with DOT 4 or 5.1 fluid only.

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Radial 195 Clutch Master Cylinder

The Radial 195 Clutch Master Cylinder comes with a piston diameter of 13mm. It has a long lever blade, with a lever ratio of 1:5.

Aluminum in colour and approximately 280g in weight, it is suitable for mineral oil only.

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HC3 Clutch Master Cylinder

The HC3 mineral oil master cylinder clutch includes the new patented technology from MAGURA, designed to improve the feedback from your brake system.

The reduced internal friction will offer a connected feel which improves performance of your brakes. The HCT hydraulic master utilises a slotted piston and a stationary primary piston seal and is approved for use with all hydraulic motorcycle braking systems with or without ABS.

It boasts a 3 way lever ratio and folding lever blade, supported by titanium retaining bolts and aluminum body.

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Workshop Braided Clutch/Throttle Cable Kit

If you have existing braided brake lines on your bike, but the leap to a hydraulic clutch is out of reach, one popular alternative is to replace the existing cables with Braided Conduit cables. This cable kit includes everything you need for upgrading your motorbike clutch and throttle cables. It comes with 20 meters of stainless-steel braided conduit, with a clear PVC cover. The conduit is fully lined and supplied with 20 metres of galvanized inner wire.

A range of nipples and high-quality chrome fittings are included.

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Learn More with Venhill

If you’re looking to change your master cylinder or improve the overall braking performance of your bike, we have a whole host of products perfectly positioned to help you. Our braided brake lines, cables, components and fittings offer a quality yet affordable solution.

For help, don’t hesitate to get in touch with our expert team here at Venhill. With over 45 years’ experience, we understand how to get the most out of your bike.

Our hoses and cables are made in the UK to the highest possible standard. We ship our products to distributors all over the world and sponsor some of the best MX and Superbike race teams in the U.K.

Browse the online shop today.