Hello,

I have a 1973 Tiger 750 Triumph.

I have been using Castrol 20w50 4T Motorcycle Oil for quite a few years.

The rating was: API SG, JASO MA1

I cannot find this oil now:

Advance Auto showed online & said that it could be ordered at the store, but store was unable to order.

It maybe available from Amazon - but what I saw online is rated: JASO MA2.

I use to buy from O'Reilly's but now they sell MasterPro 20w50 Motorcycle oil as a replacement.

MasterPro is also rated as "JASO MA2.

I did purchase 3 quarts of "Valvoline Motorcycle 4-Stroke 20w50" - Rating JASO MA2 API SL from AutoZone.  I did see one review online from an owner of a 1971 Triumph that gave the oil a good rating.

It seems that JASO MA1 is unavailable?

JASO MA2 from what I have read appears to be for motorcycles with Catalytic Converters.

Also, from what I gather MA2 has a higher coefficient of friction thus a wet clutch will grab more?

The Valvoline says: "Excellent Wet Clutch Protection"

The oils above are all convention oils.

My Clutch has worked perfect on the Castrol, since I rebuilt the Clutch a couple of years ago.

I will probably use the Valvoline Oil that I purchased, but thought someone might give me some feed back or thoughts on the issue.

Thanks, Don