JASO T903 and T904: What Motorcycle Oil Standards Actually Mean (2023 Update)

MA, MA1, MA2, MB — What They Mean

Grade	Clutch Type	Friction Level	Use Case
MA	Wet clutch	Moderate	Standard spec, safe for most bikes
MA1	Wet clutch	Lower	Older bikes or smoother feel
MA2	Wet clutch	Higher	Sport, aggressive riding, towing
MB	NO wet clutch	Very Low	For scooters/CVT only – 🚫 NOT safe for wet clutches

JASO oils are classified by how they perform in wet clutch testing

🛠️ Mechanic Talk: If your clutch runs in oil (wet clutch), MB is a no-go. Use MA or MA2. MA2 gives you extra bite — especially under torque or heavy load.

If you're wondering about the difference between MA vs MA2 oil, it comes down to friction performance and clutch feel.

Choosing the right wet clutch oil rating helps avoid slippage under load.

Chart showing JASO MA, MA1, MA2, and MB oil classifications and wet clutch compatibility

JASO Oil Classification Chart – MA and MA2 are wet clutch safe. MB oils offer low friction but are not suitable for motorcycles with wet clutches.

Picking the Right Oil

Riding Style	JASO Grade	Why It Works
Commuter / All-around	MA or MA1	Balanced grip and smoothness
Sport / Track / Aggressive	MA2	Higher friction, better clutch lockup
Touring / 2-up / Loaded	MA2	Grabs better under weight and heat
Scooter / CVT	MB	No clutch to worry about

✅ Most riders should choose MA2 — it's compatible, high-grip, and futureproof.

FAQs About JASO Certification

Find Products for Your:

Where to Buy / Become a Dealer

Looking to buy AMSOIL?

✅ Find the right product

✅ Shop online now

✅ Become a Dealer and save even more

Powered by Vyscocity

Built by Vyscocity to help you get the job done right — whether you're riding, wrenching, or running a fleet.

Explore our products, try our free tools, and let us know how it works for you.

❓ Still stuck? Ask your question on Facebook →

No fluff. Just function.