apologies if this is somewhere in that long list,
[quote name='dapleb' date='Mon 22nd Mar 2010, 03:39 PM' post='155567']
snip
JASO MA rating, is the motorcycle rating for NO clutch slip. You won't see that on a car tin, so if you are worried I would go for a motorcycle JASO MA rated oil. As long as its JASO MA rated then you can choose from mineral, semi or full synth depending on which piece of poor/not at all backed up/guessing/"my engine has had it for years and runs fine" type opinion you would like to select.
ADD
A premium quality motorcycle engine oil can be stated to meet the requirements of API Service Classification SJ, SH, SG, SF, CH-4, CG-4, CF-2, CF and CD. Note that SH, SF, SG and CD are now obsolete. Motorcycles specifying an oil meeting any of the obsolete applications can use an oil with the newer classification oil because it includes, and supersedes, the requirements of the obsolete service classification. For example, if you have an old motorcycle that specifies SE service classification you do not have to go out and look for an oil with that service classification (and if you did you would most likely not be able to find any in stores as SE was outdated in 1979). The newer classifications include the outdated ones and are perfectly suitable for use. There are some motorcycle oil manufacturers that will include an older service classification on the bottle to so that consumers can specifically see that the oil not only meets all the older specifications but the newer ones as well.
Read more:
http://www.smartsynt...m#ixzz0iwP5tG8n
I run Castrol GTX car enjun oil in a mkI after Snorv used it in his mkI and had no immediate issues. Several reasons, despite trying very very hard I cant get the clutch to slip with this stuff, mkI and mkII drink oil if ridden in a certain manner so its cheaper to buy and easier to find, if car oil is doing terrible terrible nasty things to the inside of my enjun I am happy to accept the consequences. [quote]
ADD
It is important to note that as an oil classification is superseded by a newer one, that the newer one provides improved benefits over the older one in such areas as high and low temperature deposits, wear, rust and corrosion for example and is perfectly suitable for use. All quality motorcycle specific oils should also carry the JASO Motorcycle Specifications, which are either the JASO-MA specification (no friction modifiers) or the JASO-MB specification (with friction modifiers). The JASO-MA rating specifies that no friction modifiers are used. Note that the JASO-MB motorcycle does have friction modifiers, but is designed for motorcycles that specify the JASO-MB specification. If the oil does not carry one of these specifications, even if the other specifications listed above are present, We recommend finding an oil that has the proper JASO specification clearly labeled on the bottle.
Read more:
http://www.smartsynt...m#ixzz0iwPVkz1n
SNIP
and i also use castrol or similar in my Mk1
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