Search Suggestions
Categories
Products
View All Results
For riders after the best all-round protection for their engine, gearbox, and clutch, fully synthetic 4-stroke engine oil is usually the natural choice. Built from advanced base oils, it offers stronger resistance to heat breakdown and better cold-start flow than semi-synthetic alternatives, while remaining kinder on the wallet than premium ester-based oils. This range covers a wide selection of JASO and API-rated oils to suit most 4-stroke motorcycles. Shop the full range below.
Filter Results
56 Products
Fully synthetic 4-stroke engine oil for motorcycles has to do four jobs at once - lubricating the engine, protecting the gearbox, cooling the engine and allowing a wet clutch to operate correctly without slipping. This makes motorcycle-specific formulations, rather than car engine oils, the right choice for the vast majority of 4-stroke bikes.
Most fully synthetic 4-stroke oils are rated to the JASO MA or MA2 standard, which sets a friction requirement specifically to ensure the oil won't cause your wet clutch to slip, alongside an API service rating covering general engine protection. Compared to mineral or semi-synthetic alternatives, a fully synthetic oil offers better resistance to breaking down under high engine temperatures, improved flow during cold starts, and generally longer intervals between oil changes, making it a popular choice for riders who want strong protection without stepping up to a premium ester-based oil.
Not sure which fully synthetic oil suits your bike, or whether it needs a JASO MA or MB rating? Our team of friendly experts are always here to help - get in touch for recommendations and advice. If you want the very best in lubrication technology, take a look at our ester synthetic 4-stroke range instead, or browse our full 4-stroke motorcycle engine oil collection to compare all the specifications and oil types we stock.
Both are designed for wet clutch compatibility, but MA2 sets a higher friction requirement than standard MA, and is typically specified for high-performance and sports bikes. Always check your handbook for the correct rating.
Fully synthetic oil generally offers better heat resistance, cold-start performance, and longer service intervals than semi-synthetic, though semi-synthetic remains a solid, more affordable option for many everyday bikes.
It's best avoided in most cases, as car engine oils aren't formulated to meet the friction requirements of a wet clutch and can cause it to slip. Always use a motorcycle-specific oil unless your handbook states otherwise.
As the UK's largest independent supplier of automotive and motorcycle oils, fluids, and parts, we stock a wide range of JASO and API-rated fully synthetic oils, backed by more than 15,000 genuine 5-star reviews on reviews.io. Our team offers free expert advice if you're unsure which oil suits your bike, and every order comes with 60-day returns for extra peace of mind.
Shop fully synthetic 4-stroke engine oil at Opie Oils today, with free UK delivery on orders over £80 (geographic restrictions apply) and our no-leak guarantee on every order.
