aah, the old 'friction-modified' wives tale pops up yet again.
Wives tale maybe, but after changing many many clutches after working in Yam and Kaw dealerships, you get sick of seeing people try to save $10 on oil and then have to spend up to $700-$800 (particularly in ATV's where you have to change the whole centrifical clutch and hub assy as well). In rural areas you see a pattern when a local distributor starts flogging an oil not stated as suitable for motorcycles, only to have a run of clutches in the following months. Rimula X, RX super, Delo400 and similar diesel oils are ok as the are also designed as a multi-purpose oil for some transaulic applications in rural machinery, where the engine, trans and hydraulics run the same oil, and some of these trans have a wet clutch arrangement for the hi-lo or powershift. "Friction modifiers" may be an old term, but the additives (or similar) are still out there and used in some oils. Unless it states suitable for motrcycles, why use it? Also remember that some companies sell to likes of Kmart etc, and although the oil might be called the same, the product in the bottle looks completely different. Maybe the same spec, but enough to think, things that make you mmmmmmmmmmm.

A lot of product at supercheap is fine, but check first
Airfilters on ZZR's are required to stop scooters, pedestrians and small animals getting stuck in your intake ports!