Scooter transmission oil is SE = EP

use ordinary engine oil of 10/30 grade, you will find that they are graded sd/se/sf/sg/sh, basically the better the quality the higher the letter.

mrcheerful

No SE should read SAE. It's engine oil. There won't be much pressure in a two stroke they work on whizzing aluminium, not pumping iron.

I imagine that the self mixing modern engines pump the oil through the crank journals and needs to be fairly fluid. I worked in a saw mill once and almost everything except the hydraulics were running on diesel as a lube, even the chainsaws.

It's gearbox oil, not total-loss two-stroke lubricant. He should go to a motor factor, and read the side of a container of 10/30 to see if it's good enough.

The message from "Weatherlawyer" contains these words:

Don't know about now, but they /used/ to just dribble it into the inlet port just downstream of the carb.

Guy King wrote in news: snipped-for-privacy@zetnet.co.uk:

Both true, but that lubes the crankcase.

There's also the gearbox and perhaps final drive; I think that's what dave means.

Ex bretta fancier

mike

The message from mike contains these words:

Yup - and just about any gear oil would do, I suspect.

Yes that's right. The handbook says "SAE 10/30 SE" (so the SE is not a typo). I just wondered because in car rear axles for example the oil is usually specified as EP is it not. So I thought maybe SE was some kind of EP "thing" for scooters.

he is asking about transmission oil, not engine oil.

mrcheerful

The message from "mrcheerful ." contains these words:

I know that, but the subject had drifted onto 2-stroke oil and I was answering the comment about self-mizing 2-strokes pumping the oil through the crank.

Oh, c'mon. Thread drift? In uk.d-i-y? Happens all the time, where sooo many posters have this irrestible urge to air their (sometimes limited or misleading[1]) knowledge. :-)

Not at all. EP is for use with hypoids back axles which have sliding contacts that generate "extreme pressure" contacts. This needs a lot of extra additives in there which aren't a good thing for general oiliness.

In particular, EP oils can destroy some bronze components, particularly gearbox dogs and synchro rings. Don't put EP somewhere that doesn't want it, you really might break something.

"SE" is a quality rating, mainly for expected lifetime in hot engines. SE oil can be replaced by SF, SG, SH, SI etc. - each grade being progressively better. You don't need these good heatproof oils in a mere transmission. It's getting hard to find the lower S ratings though!

Don't use synthetic oils in things that didn't always use them, or don't need them. Synthetic oils have ligh lubricity and will tend to leak through oil seals that were perfectly adequate with mineral oils. They're good in modern, clean engines, but a risk of trouble in other things.

On any motorbikes, always follow the maker's recommendations. You probably have a wet (oil-bath) clutch in there and it's fussy.