Gear oil replacement questions

[kymcofan1]

I have a Kymco Agility 125 with 3,000 km and I've changed the gear oil a few times now. I'm new to bikes, but I've worked on many cars before. The manual says to put something like 180cc in after you drain, but I've just been adding an equivalent of what comes out by comparing two clear cups side by side, because not even close to 180cc comes out and I wanted to avoid overfilling it.

Here's my question, should I be adding 180cc, regardless of how much comes out, because gear oil burns up and that's why they want more to go in, or will adding more than what drains every time just overfill it eventually. Like I said, I'm new to this, so any advice is welcomed.

[Ruffus]

@kymcofan1, welcome here!
Filling this amount which came out might be sufficiant, but be sure to have enough gear oil in it.

Too much of oil would result in spoiling your AIRFILTER through the gears breather tube.

In short, empty completely at warm motor, fill 150-180 ml and you have your peace of mind.

Edit: pls see maint. schedule

[Neil955i]

Welcome here kymcofan (aren’t we all?).

According to this:  https://vachiraphuaklek.wordpress.com/2013/12/11/changing-your-scooter-gear-oil/ you should be draining off close to 180 ml if following the guidance?  If not, I’d be tempted to refill with 180 ml and then see what drains off next time? Checking the air filter in the meantime as Ruffus suggests.

[Stig / Major Tom]

And, no - gear oil doesn't burn up.
Welcome!

Stig

[Vision]

I suggest you put 180cc in each refill, and a syringe is best for that. In my experience less than 180cc drains out during an oil change and I don't know how that's possible since nothing is leaking.

BTW, do not use a torque wrench to tighten either of the two gear oil bolts to the specs in the manual. That housing metal is soft and you will probably strip the threads which will cause serious issues. Hand tighten and leave them alone.

I change the engine oil every 2k and the gear oil every 4k. Mobil 1 75W-90 Synthetic Gear Lube is best and do not recommend using Royal Purple brand.

[Stig / Major Tom]

I have a Kymco Agility 125 with 3,000 km and I've changed the gear oil a few times now. I'm new to bikes, but I've worked on many cars before. The manual says to put something like 180cc in after you drain, but I've just been adding an equivalent of what comes out by comparing two clear cups side by side, because not even close to 180cc comes out and I wanted to avoid overfilling it.

Here's my question, should I be adding 180cc, regardless of how much comes out, because gear oil burns up and that's why they want more to go in, or will adding more than what drains every time just overfill it eventually. Like I said, I'm new to this, so any advice is welcomed.

If you have time for a little experiment to see if your scooter is keeping secrets..drain your gear oil, refill with 180cc, drain it again into a measuring device. See what amount drains out now.
Yoj might find something interesting.  Some fill figures are based on filling a totally dry gear case after a rebuild....while other figures are that used for routine servicing.

Stig

[jeeves]

I have a Kymco Agility 125 with 3,000 km and I've changed the gear oil a few times now. I'm new to bikes, but I've worked on many cars before. The manual says to put something like 180cc in after you drain, but I've just been adding an equivalent of what comes out by comparing two clear cups side by side, because not even close to 180cc comes out and I wanted to avoid overfilling it.

Here's my question, should I be adding 180cc, regardless of how much comes out, because gear oil burns up and that's why they want more to go in, or will adding more than what drains every time just overfill it eventually. Like I said, I'm new to this, so any advice is welcomed.

Why have you changed your gear oil a few times in 3000km?!

I do it every 6000km, and even that is a bit overkill.

[Vision]

I do it every 6000km, and even that is a bit overkill.

You think so? Doesn't the manual say 4k?

[jeeves]

You think so? Doesn't the manual say 4k?

There are a few gears inside an enclosed casing bathing in gear oil transferring less then 10hp to the rear wheel.

Every car that I have had has gone more then 150000km. All manual transmissions. The gear oil has never been changed in any of them.
Kinda makes you think.

[monkeybongos]

Manual for the Cali 200 recommends gear oil change every 3100 miles.  Since the recommended engine oil change every 620 miles seems overkill (I change it at 1100 or so), I'm guessing the gear oil change is also.  But it makes sense manufacturers want to error on the side of safety.

[Ruffus]

There is a good reason why to change gear oil in our KYMCOS. It's called wear.

 In difference to an car gear this small gear is mounted without any rubber shockers directly to its CVT case. Then this small amount of oil has to bear with a lot of inconveniences like heat, straight sprockets, exit shank direct to the wheel, etc.

So there are many more stressors which cause this oil to boil up.
Even 4k km seem to be little overdone, better to change regularely with prime stuff.

[Stig / Major Tom]

Each gear oil change is so inexpensive - even with the best stuff - because our scooter requires such a small amount.
(Same for engine oil changes. )

I do wish Kymco would simplify things by......"drain, then fill until new oil begins to flow from fill hole. Wait a bit, then reinstall the plug. Do NOT overtighten!!".......like is used on so many scooters.
Stig