Choosing the right motorbike oil: What does JASO and JASO MA2 mean?

What does Jaso mean?

What does the JASO MA and JASO MA2 Motorcycle Oil Standard Mean?

In 1998 the Japanese Automotive Standards Organization (or JASO for short) developed a grading system for motorcycle oils.

The grading system measured (amongst other things) an oils ability to resist clutch friction (or slippage), protection offered against engine wear and pitting in the gear box.

Up to 1998 car oils had been used as the base for many motorcycle oils. As car technology evolved over the years the oils that cars needed changed and additives were added that weren’t good for motorcycle engines (especially motorbike clutches and gearboxes, mainly due to the fact that, unlike most motorcycles, cars use a separate oil for the gearbox).

Car oils had been blended using more and more friction modifiers, which, although good for cars, wasn’t too good for motorcycles as these modifiers can cause clutches to slip at higher revs and gearbox pitting.

JASO introduced 2 ratings for 4 stroke motorcycle oils:

JASO MA – This was the standard for single unit engines where the wet clutch, gearbox and engine used the same oil. JASO-MA oils don’t contain friction modifiers.

JASO MB – This lower standard was for bikes that use separate oils for the engine, clutch and gearbox (e.g Harley Davidson’s and BMW’s).

Then in 2006 JASO introduced…..

JASO-MA2 – This specification was introduced in 2006 for  modern motorcycle engines. As well as being a higher standard of oil the JASO-MA2 approval means the oil is suitable for use in bikes with catalytic converts in the exhaust system.

JASO also introduced a rating system for 2 stroke oils. Modern 2 stroke bike and scooter engines have much finer tolerances and low ash burn (which means less smoke) and need a higher specification 2T oil.

JASO 2 stroke oil classifications (JASO-FA is the lowest spec, JASO-FD is the highest):

JASO FA – This is the lowest 2 stroke oil spec that tests lubricating capability, detergents, initial torque and exhaust smoke.

JASO FB – This spec tests the same things as JASO FA but is a slightly higher standard.

JASO FC – This spec has the same level of tests as JASO-FB for lubricating capability and initial torque. But it has much higher standards for detergents and exhaust smoke.

JASO FD – This spec is almost the same as the JASO-FC spec but with much higher detergent capabilities.

The JASO specifications are the Japanese equivalent to the American API standard and were introduced partly because the API standards used for oils weren’t up to the job for modern engines.

Where to find the JASO information on an oil bottle…..

Normally the JASO and other oil specification information will be printed on the back label.

Silkolene Motorcycle Oil JASO information (4 stroke):
Silkolene 4T Jaso info

Rock Oil JASO information (4 stroke):
Rock Oil 4T Jaso info

Silkolene Motorcycle Oil JASO information (2 stroke):
Silkolene 2T Jaso info

Rock Oil 2 Stroke Oil JASO information:
Rock Oil 2T Jaso info

A few point’s to consider when selecting a JASO approved oil…..

Engine oil is an amazingly complex subject and (unsurprisingly!) the approvals that are used to rate the oil are complex (and vague!). There are a few point’s to consider before you part with your hard earned cash when buying oil.

1) You get what you pay for!

When buying oil (with only a few exceptions!), you get what you pay for. So if you are offered 4 litres of ‘fully synthetic’ 10w40 ‘JASO MA2’ approved motorcycle oil for £25, you can bet all your ££ that it WON’T be fully synthetic and would be very unlikely to pass the JASO MA2 test!

2) Cheap/workshop/etc 10w40 oils aren’t suitable for all bikes!

If you’ve got the latest Ducati/Honda/Yamaha/KTM/etc Muchofasti bike, there is a chance you may need to bite the bullet and buy a more expensive oil for it (when you see up close the very fine tolerances modern engines work to you begin to understand why, sometimes, the cheapest oils just aren’t worth the risk!)

25 thoughts on “Choosing the right motorbike oil: What does JASO and JASO MA2 mean?”

  1. “you get what you pay for”
    I bought Repsol 4T sintetico 10W40 for usd 8 @1 liter which state in the label as fully synthetic which meet JASO MA2 -API SJ.
    is it to good to be true consider the brand name so well known.

  2. The botle color and label exactly identical ,except one said”fully synthetic” under 10W-40 with JASO MA2 and the other not stated the oil type and only meet JASO MA.quite deceiptive I think.
    Because of that I accidently mixed those oil in my motorcycle.

  3. It’s important to note that only JASO MA & MA2 certified motor oils have the JASO box ( on the back of the bottle ) and individual certification number located on the top of the MA or MA2 logo.
    SILKOLENE and ROCK motorcycle oils only state that they ” meet or exceed” JASO MA or MA2 requirements – not tested or certified JASO ( Japanese Automotive Standards Organization ) performance.

    1. Yes, if the oil has been tested and passed the relevant JASO spec, it should have a box with the appropriate JASO number on it.

      Just for your info though, nearly all Silkolene motorcycle oils have the JASO box and relevant number on the back (where the oil needs to be JASO approved).
      Some higher level Rock Oil motorcycle oils USED to display the JASO box and number on the back (I know Guardian used to have the JASO box). But, as Rock are a fairly small company, they haven’t kept up with getting their oils tested by JASO due to the cost of getting the oil tested once a year (to use a direct quote from Rock Oil: ‘It isn’t mandatory and is very expensive without adding anything meaningful‘).
      However, Rock Oil do have their own, in house testing facilities to make sure the oil meets the spec and, after a recent email from them, they are in the process of having some of their Guardian Motorcycle, XRP and Synthesis Motorcycle ranges tested and approved.

  4. Hello. I just got a kawasaki genuine oil witch says on the label and it’s graded 20W50 JASO MA2 API SG. Is this a good oil for my rouser 135ls?

  5. i just bought a rouser ns 200 and i could not find the oil that the maker recommend which is sae 20-50 / jaso ma2 /api sl can i use the sae 20-50 /jaso ma/api sl

    1. JASO MA2 is a higher/stricter standard and means the oil is safe to use in bikes with catalytic converters in the exhaust.
      Some good 20w50 oils will pass the JASO MA2 standard (even though they only state JASO MA on the label).
      You would be better off checking with the bikes manufacturer or an official dealer to make sure.

  6. My scooters’ recommended specification in engine oil is JASO MB. My question is, can I use JASO MA/MA2 on my scooter? Thanks!

  7. I had a z50 in 1970 that i rode for 10 years… back then , we had can oil, quarker state 10 w 40.. motor oil…not motorcycle oil just motor oil.. over 100000 miles , I did change every 6 months.. I did a rebuild in 1980…It showed normal wear. I thick that this rating system , and oils being made cheaper like gas,,, is why you need to pay 9.95 qt.. it was only 65 cents in 1970~better qualiy by far

    1. Yes, back in the day there was normally only 1 oil available for both cars and bikes.
      However, engine technology has moved on alot since then and modern car and bike engines are machined to much finer tolerances (hence the need to add additives to the oils that weren’t available in the 1970’s).
      Modern oils are (generally!) much better quality now compared to the older counterparts, mainly due to better blending processes and additives that are available.

      Modern oils are more expensive, yes, but part of the price is due to inflation (nothing stays at 65 cents forever!).
      Also, the actual cost of the oil has very little bearing on the price of modern oils, most of the cost of the oil is made up of processing, additive and packaging costs (which is why retail oil prices tend to stay the same whether oil is going up or down in price).

      As to the the same oil being used in both cars and bikes (as happened in the 1970’s and 80’s), modern engines need additives to keep the metal parts running correctly and not all these additives are suitable for all engine types (which is the main reason we have different car, bike, truck etc oils now).

      In short, modern oils are more expensive by comparison, yes, but they are much better quality…..

Leave a Reply

Your email address will not be published. Required fields are marked *

Anti-Spam Quiz: