50cc Chinese scooter & its gear oil change interval

Why such a short drain interval on the transmission oil?

My neighbor rides one of these (a Taotao 50cc Gator)… his primary transport. He knows I’m into classic motorbikes, so today he stopped by to ask me if i could tell/show him how to change the oil, adjust the brakes, etc. I said, “Bo, I don’t know nuthin’ `bout no scooters, but i’ll take a look”.

Well, I was able to figure most of it out upon inspection, so i’m good w/ that. But why-o-why does the mfg recommend changing the tranny oil every 5000km or 6 months? I’ve owned machines in which I’ve never changed the trans oil… certainly not every 3000 miles. What is it about these machines’ trannys that soils the oils so quickly?

It looks like Taotaos are four strokes. Do the engine and trans share oil?

That was my first thought. However they do not share oil. Seems that the it’s a CVT transmission. A small Constant Velocity Transmission might just need extra care to keep working properly.

Continuously Variable Transmission

That’s what happens if I start typing before my first jolt of caffeine. :smack:

My WAG is that CVT transmissions run hotter than a conventional gear transmission. That would cause the lube to break down over time.

Anyone know if that is plausible?

If it’s a steel belt/pulley type, then yes. There’s a tremendous amount of shear the oil is subjected to.

If it’s a crudely made item (at least by modern standards of what’s crude & what’s not), then it’ll tend to shed more shavings faster than a more precisely machined and hardened set of components.

Short oil change intervals will offset that to some extent. “Cheap to make, cheap to buy, not very durable” has been a motto of certain Chinese producers for decades now.

I’m not suggesting this *is *the case for a Taotao specifically, but it might be.

Service intervals in general also just tend to be very short for scooters. 3,000 miles on a scooter is a lot more hours and a lot more wheel and engine revolutions than it is on a car or full size motorcycle.

That’s probably only one change in the life of the engine, so no big deal.

Could there also be a component of the gear oils produced by the “People’s Glorious Refinery #163” are about where the gear oils of the Western world were in 1953, thereby necessitating much more frequent oil changes than we’re used to?

Ha, that cracked me up. I can imagine the look on his face if I quipped that little gem his way.

Well, you’ve got something there. Everything is smaller so it’s gotta be turning quicker. Plus, with >200 pounds of human on there, those 3 ½ tablespoons are working harder, too.

The engine and tranny are certainly 2 different units with their own lubricant. There are different/separate fill & drain plugs on each. With that being said, I assume any automotive engine oil would work in these scooters, right?

I’m not familiar w/ CVTs, yet. Are the drain intervals shorter on other engines (cars, lawnmowers, etc.) that use those types of transmissions?

I would go for an oil designed for diesel engines, without the friction modifiers added in. Shell Rotella T (Blue jug, not white) 5w40, is probably perfect for this. I use it on my race bikes, street bikes, and motocross bikes.

Use whatever the mfg recommends. We don’t know if that’s motor oil, gear oil, ATF, or hydraulic fluid. But whichever of those classes of fluid it is, anything from a different class is certain damage and failure.

My TaoTao scooter recommended 10W-40 for the engine and 80W-90 gear oil for the transmission. I’d also change out the spark plug for an NGK plug (don’t remember the number). I’ve also seen it recommended to ditch the tires that come with it and get better ones. I never did that though.

It’s very likely that this is the reason. A lot of us old folks remember when we had to change our oil every 3,000 to 5,000 miles. Engines were just a lot cruder back in those days.

Modern manufacturing is more expensive, and Chinese (non-joint-venture) companies hate to add expenses, so I would venture this is one of the places they cut corners.

FWIW, it’s a design and manufacturing issue, and not necessarily a “made in China” issue (disclose that my company makes high quality engines in China).

GAH! I missed that it was a CVT!

I worked at a Yamaha dealership back in the late 1980s. Their scooters at the time used rubber belt CVTs. The belts would melt and wear away, and would clog the pulley weights. The replacement parts were beyond the budget of most of the owners, so we would just replace the belts and clean things up as best we could. Your transmission is probably a little better in that it has more metal parts, also the oil cools things a bit and keeps the crap in suspension, but its still built to shed a little as it goes. By god, please, dear god, please, change that oil!

Yup. I’m that old too. Oils were a lot cruder (hah!) then to boot.

And I agree that low durability is much more a matter of business culture than it is technical capability. Even in the West, things are made only as well as they “need” to be. It’s just that we have a different conception of what’s needful.

The Wild West stage of capitalism encourages shortcutting. We’re past the Wild West in our mechanical industries, but are still fully within it in IT / software. Hence the quality issues in software and websites where the rush to market trumps (almost) all other concerns.