Castrol, a long-established British lubricant manufacturer, and Motul, a French company with over 160 years of experience, are among the leading brands in the field of high-quality engine oils. The Castrol A747 2T oil range has been specially developed for aviation applications, while Motul 800 has been designed as a premium two-stroke oil for motorsport. Choosing the right two-stroke oil is crucial for engine performance, wear protection and emission control in specialised applications. This comparative article analyses both product lines in detail to provide users with a sound basis for decision-making.
API TC certification: Both oils fulfil the strict API TC requirements for two-stroke engines, which guarantee high performance standards, cleanliness and wear protection.
Two-stroke specialisation: Developed as premium lubricants for demanding two-stroke engines with high thermal and mechanical loads.
High-temperature performance: Both product lines offer reliable protection at elevated operating temperatures thanks to advanced additive packages.
Miscibility with petrol: Full compatibility with various fuel qualities for precise oil-fuel mixtures.
Corrosion protection: Special corrosion inhibitors protect metal components from oxidation and moisture during operation and downtimes.
Reduced deposits: Both formulations minimise carbon deposits on pistons, rings and exhaust systems.
Professional application: Designed for use in professional or demanding environments with high quality requirements.
Precision engineering: Developed with the latest lubricant technology for optimum engine performance and longevity.
Differences: Castrol A747 vs Motul 800
Characteristic
Castrol A747
Motul 800
Oil base
Mineral/semi-synthetic
Fully synthetic with ester technology
Main strength
Aviation certification and altitude suitability
Motorsport performance and high speed optimisation
Temperature resistance
Optimised for constant flight conditions
Designed for extreme load changes in racing
Target group
Aviation pilots, aircraft maintenance
Racing drivers, motorsport enthusiasts, performance users
Product selection
Specialised aviation range
Extensive two-stroke portfolio for various applications
Manufacturer approvals
DEF STAN 91-37, aviation specifications
JASO FD, various motorbike manufacturer approvals
Performance optimisation
Reliability and safety in aviation
Maximum power output and speed stability
Smoke behaviour
Moderate, in accordance with aviation requirements
Extremely low smoke for modern environmental standards
Conclusion
Castrol A747 and Motul 800 represent highly specialised two-stroke oils for completely different areas of application. While the A747 was primarily designed for aviation applications with strict safety and certification requirements, the Motul 800 is aimed at motorsport enthusiasts and high-performance two-stroke engines. Aviation operators and pilots benefit from the aviation certification and altitude suitability of A747, while racers and performance orientated users should prefer the fully synthetic ester technology of Motul 800. Both products fulfil the highest quality standards in their respective segments and offer no direct interchangeability due to their specific development goals.
Frequently Asked Questions (FAQ)
Can I use Castrol A747 in my motorsport two-stroke engine?
Castrol A747 is primarily developed and certified for aviation applications. Although it will technically work in other two-stroke engines, it does not offer the specific motorsport optimisations of Motul 800. For racing applications, a specialised motorsport oil such as 800 is recommended.
What is the recommended blend ratio for Motul 800?
Motul 800 is designed for blend ratios of 1:80 to 1:100, depending on engine type and load. For racing applications, 1:80 is often used, while 1:100 may be sufficient for moderate conditions. Manufacturer specifications should always be observed.
Does Castrol A747 fulfil modern environmental standards?
Castrol A747 fulfils aviation standards such as DEF STAN 91-37, which define specific requirements for aviation applications. These differ from road vehicle emission standards. The oil is optimised for its application, but is not primarily designed for minimal smoke development like modern motorsport oils.
Is Motul 800 suitable for outboard engines?
Yes, Motul 800 is suitable for high performance outboard engines and fulfils the JASO FD specification. It offers excellent protection for water sports two-stroke engines, especially at higher speeds and loads. The reduced smoke formula is favourable for water sports applications.
What is the shelf life of Castrol A747?
Castrol A747 is characterised by excellent long-term stability, typically 3-5 years when stored properly. It should be stored in a cool, dry and sealed place. Before use after a longer storage period, the oil should be checked for discolouration or sediment formation.
Does Motul 800 require special additives or additives?
No, Motul 800 is a fully formulated solution with all necessary additives. Additional additives are not required and may even affect the balanced formulation. The oil should be used directly as supplied by the manufacturer.
Which oil offers better wear protection in extreme conditions?
Both oils offer excellent wear protection in their specific applications. Castrol A747 is optimised for constant loads at high altitudes, while Motul 800 has been developed for extreme load changes and high speed conditions in motorsport. The choice depends on the specific application.
Manufacturer recommendations: PSA B71 2296, GM LL-B-025, MB 229.5, Porsche A40, VW 502 00, Renault RN0710, Fiat 9.55535-H2, Fiat 9.55535-M2, Fiat 9.55535-N2, Renault RN0700, VW 505 00, BMW Longlife-01
3 February 2026 (updated) 
