I've just been looking at the spec on the rock oil I got with my bike and it dosen't match the 

castrol one that's in the manual, the rock oil is also nearly clear so its a pain to see it in the 

sight window as the red one that came in the bike you could see a mile away 

Lite_Gear_Oil.pdf

In cars, ATF oil have to be changed in intervals like 100.000km. Why on motorcycles we have to change it after 100km or less???

For the most part, volume. A car holds several liters. Our bikes generally only hold 400mL or less.

I'm not an automatic gearbox expert, but I'd imagine they also do far less clutch slipping than we generally do, which means a lot less particulates in the oil.

Edited October 17, 20178 yr by heffergm

3 hours ago, cascao said:

In cars, ATF oil have to be changed in intervals like 100.000km. Why on motorcycles we have to change it after 100km or less???

ATF usually needs changing at 50K ideally, engine oil at perhaps 10K on a modern car, or 3K on an old one.  Most motorbikes use combined gearbox and engine oil, and have a wet clutch (rather than an automatic gearbox's belts and torque converter, which is a seperate fluid coupling) which means it all gets dirty faster; trials bikes also don't have an oil filter, which is why I can do 4K between oil changes on my Triumph but a fraction of that on the Gasgas.

4 hours ago, turbofurball said:

ATF usually needs changing at 50K ideally, engine oil at perhaps 10K on a modern car, or 3K on an old one.  Most motorbikes use combined gearbox and engine oil, and have a wet clutch (rather than an automatic gearbox's belts and torque converter, which is a seperate fluid coupling) which means it all gets dirty faster; trials bikes also don't have an oil filter, which is why I can do 4K between oil changes on my Triumph but a fraction of that on the Gasgas.

Modern auto boxes have clutch packs very similar to pre diaphragm trials clutches and epicyclic gear sets very similar to the small gears in trials bikes.

Fair doos, I've never had to do work on a modern auto - probably for the best, lol

I'm not over keen on the rock oil, its that light you struggle to see it through

the sight glass, where the red that came in it from new you could see a 

mile away 

We switched at the last change to the Castrol Transmax Z as Chris was losing clutch feel as the oil warmed. Not had any problems since. Helpful it's longevity seems to be good.