Motorcycle engine oils & fluids

Alongside regular oil checks, monitoring and replacing your motorcycle’s brake fluid is another important part of motorbike and scooter maintenance. Discover the full range of Castrol brake fluids below.

• Castrol Brake Fluid DOT4
• Castrol React Performance DOT4
• Castrol React SRF Racing

Safety information

Brake fluid is crucial to ensuring safe stopping distances on the road. Selecting the wrong fluid could lead to longer stoppage distances and potential accidents. 

When should I change my brake oil?

Most manufacturers recommend changing your brake oil every 24 months or 24,000 miles. At Castrol, our experts additionally suggest checking brake fluid at every service, ideally using a professional servicing machine.

How to understand brake fluid specifications

Brake fluids are rated and then categorised into DOT ratings. To understand more, visit our helpful guide about understanding brake fluid specifications.

Motorcycle coolant plays a vital role in the lifecycle of your vehicle. Motorbike engines often perform under more extreme conditions than other automobiles, and our advanced coolants are designed to prevent overheating and system malfunctions. Motorcycle coolant should be changed at least every two years, or 24,000 miles, but you should consult your manufacturer’s manual for your motorbike or scooter’s specific requirements. 

How do I change my motorcycle coolant?

1. Make sure your engine is cold.
2. Remove any bodywork to get to your radiator cap, reservoir tank and the drain bolt on your water pump cover.
3. Position the drain pan underneath the water pump cover.
4. Loosen the drain bolt on the  water pump cover and the old coolant will begin to drain slowly.
5. Loosen your radiator cap and the liquid will flow faster into your drain pan.
6. Flush the old coolant from your radiator using dsitilled water.
7. Once the coolant has stopped draining, tighten the drain bolt.
8. Using the funnel, fill the engine with new coolant.
9. Top up the expansion tank if necessary.
10. Start and run the engine for 2 or 3 minutes. 
11. Wait for the engine to cool again and top up the motorbike coolant if necessary. 

Castrol’s motorcycle fork oil uses an advanced fluid to provide the best damping performance for on and off-road suspensions in hot and cold temperatures. Choose a heavier oil for increased damping or a lighter oil for less – find the perfect product with the Castrol Oil Finder.

When you need to change your motorcycle fork oil, always consult your manufacturer's manual for the specified amount before replacing it. Our current fork oil is available in 10W and 15W – both feature a highly refined basestock and naturally high viscosity index that offers superior performance and protection to your suspension. 

Castrol TRANSMAX Axle Long Life 75W-90

Fully synthetic rear axle fluid formulated with Smooth Drive Technology. It provides superior protection especially when driving under stop-start or extreme conditions. This enables smoother axle operation and noise reduction resulting in a more comfortable drive.

Advantages

• Better fuel economy and less emissions 
• Superior low-temperature fluidity for optimum protection at vehicle start-up
• Longer time between drain periods and servicing
• Anti-wear, extreme-pressure performance at all ambient temperatures 
• Designed to extend the lifecycle of your gears

Castrol Chain Lube Racing

Our new spray lubricant is developed and tested to high-performance and racing specifications. It is designed to massively reduce friction on the chain while increasing durability and performance. It is resistant to high-speed fling and water wash-off and protects from metal corrosion caused by humidity and salt.

• Designed for use on sealed and un-sealed chains found on both on-road and off-road bikes
• Use Castrol Chain Cleaner before applying our Castrol Chain Lube Racing Spray to maximise your chain’s performance and durability
• Wait for 10-20 minutes for the solvent to evaporate fully before riding your motorcycle

Castrol Chain Cleaner

Our Castrol Chain Cleaner features a powerful cleaning formula that instantly loosens oil, grease, and dirt. It also works to remove adhesives and increases your chain’s durability. You can use Castrol Chain Cleaner on the following chain types: O-ring, X-ring and Z-ring. 

• Always shake well before use 
• Apply the extension tube and spray the formula evenly from a distance of 6-8 inches
• Use a chain brush to clean the area you have sprayed
• Wipe the surface with a microfibre cloth 
• Repeat the process if necessary