Forum

[wetdog]

I thought the engine and chaincase ran in the same oil , are you 100% 20/50 for the gearbox ? seams light

[Dennis C]

Yes 20/50 is fine for the gearbox, the original would have been 50 grade. You can still get it if you prefer.

[wetdog]

I have some straight 50 and feel happier with that , was thinking 90 but to heavy I guess

[papasmurf]

wetdog I really do suggest contacting our hosts.

[simon]

Not sure why everyone is so delicate on this topic. Mind you I did stuff an oil pump spindle with a high capacity pump and my usual straight 50. As far as I am aware modern synthetic oils are too slippery for needle roller bearings so you want a mineral oil. 20/50 is fine for both engine and gearbox as straight cut gears dont require high pressure (ep) oils. 90 is fine but so is 50 or 20/50. If you have a high capacity oil pump on an Indian iron barrel which has no proper oil pressure release valve then 20/50 is the go (I would expect the 250 to have a decent presure release valve but you should check the literature). The fact that 20/50 is the cheapest and most available would also make a convincing argument but to be honest it just isnt that crucial, you dont have hydralic tappets or other lubration crucial devices so use whatever but replace it regularly.

[Mark M]

I suggest buying a manual but what do I know.

REgards, Mark

[Leon Novello]

It`s most important to read the labels and use only motorcycle- specific oil as these do not have friction modifiers which make the oil more slippery, which automobile and synthetic oil contain. eg, Pentite motorcycle oil will state on the label that it does not contain friction modifiers. Then choose the recommended grade.

[wetdog]

thanks will try 20/50 for the motor , shell big end, and straight 50 gearbox and see how it goes , I have 2 spare 5 speed boxes but the one fitted now is a 4 speed , the 5 speed does look flimsy

[jefrs]

The "slippery" bit in a motorcycle oil is the "JASO MA" part, this ensures it is a waterless oil that won't dissolve the cement used on the wet clutch friction plates. The viscosity bit of a multigrade oil is the last number in its title, the "50" in "20W-50" (the "W" stands for "winter", its cold-start properties). Synthetic oils are mineral oils, they've just have improved formulation.

Personally I would shy away from cheap oils in a cherished vehicle and use the best available.

[jefrs]

Needle rollers? Hang on, that's not right, the EFI has needle rollers and it's specified oil is semi-synth.