MZ/MuZ Riders

hi, i was restoring old rt 125 i found from back of my fathers garage and now when the moment of first start up is getting closer and the engine is together again, i am wondering what oil can i use in the gearbox, also i wonder how much does the motorcycle needs it because the oil stick has vanished along the years and i have not any reliable way to confirm the oil amount.

where are you located and 2 or 4 stroke
site is world

If it is the old 2 stroke RT125/1, then you need 450 ccm gearbox oil.
And on the left side of the engine, on the clutch cover, there is an oil level control, screw. If you unscrew this screw and there is oil coming out, then the level is o.k. if not, turn the bike to the left side and check when the oil drops out. Then you can estimate how much oil is missing.

The Rs is not that far from a Ts 125 engine . The oil to be used is Hypoid 90 weight or any good 20/50 weight in anything other than Siberian type winters . The 20/50 oils have to be changed more often than Hypoid types.

As the gears chomp up lightweight oils. And 450cc of anything is better than nothing.and remember to remove any accumulated metal filings, from the the magnet on the drain plug
As there will be plenty

I don´t agree with hypoid or 20/50 oil. MZ recommends GL3 gearbox oil.
Viscosity should be 80.

Guesi wrote:I don´t agree with hypoid or 20/50 oil. MZ recommends GL3 gearbox oil.
Viscosity should be 80.

Each to their own. Mz grearboxes are tractor derived. I would use a big daub of grease actually. It's like the grearbox that drives showmen's rides. And theirs aren't half as loud

Not recommended but I had an MZ lose all its gearbox oil in Carmarthen a few years back. Anywhere selling oil was closed. Twenty miles home, having fixed the leak, on two stroke oil - changed back the next morning.

Anything oily is better than dry, but mine usually live on Silkolene Light Gear oil(75/80 as it happens).