Z750 Twin Forum

Hello again

Just wonder what kind of viscosity is mostly used on the 750 Twin engines. I use 15-40 semisyntetic oil and it seem to work well with no oil consumtion after 1000km so far. But other MC people I have talked to also say the older Japanese aircooled engines like Kawasaki, Honda, Sysuki etc. with benefit can be filled with 20-50 oil, in particular during driving in hot condtitions. 

Any opinions out there..?

Hi,
i drive 20-50 in my Twin. I drive only when it is warm, so i found it better to have a oil for hot conditions, then one for cold weather.
Please use only motor bike oil because the clutch can make trouble with semisyntetic oil. This problem is degreed with motor bike oil.

But that oil that's right , is a faith question , because there are 100 people and 110 reviews.

Hi Salaren,

Werner is right. It´s better you use over 10 degrees Celsius 20-50 or 20 - 40 Oil. I use 20- 40 Oil.

Because your cluch, use only mineralic, never synthetic oil.

Best Regards

Gerd

Hello Salaren,

same to me: I use for my old air-cooled japanese (and american) Bikes also only 20W-50 mineralic oil.

Good luck, Ralf

Ralf Wilde hat geschrieben: Hello Salaren,

same to me: I use for my old air-cooled japanese (and american) Bikes also only 20W-50 mineralic oil.

Good luck, Ralf

Good to know. But when you mention 20W-50 mineralic oil, do this oil have the specification needed for wet clutch..?

Salaren hat geschrieben:

Ralf Wilde hat geschrieben: Hello Salaren,

same to me: I use for my old air-cooled japanese (and american) Bikes also only 20W-50 mineralic oil.

Good luck, Ralf

Good to know. But when you mention 20W-50 mineralic oil, do this oil have the specification needed for wet clutch..?

Yes, it does. Because it is the same circuit system, you can use 20W50 motoroil as clutch oil, but mineralic. I prefer 20W50, because of the wider using range, and it seems to be softer to the old engines. Since I use this viscosity, it seems that the different gears goes easier, that means without clamping between the gear-changes

I do thrust you guys when it comes to oil recomandation and with your experience gained from lots of driving with Kawasaki Twins during years I will follow your advice. It is also important to make it easy, but you know, when you really start to look into something it might be more complicated then is has to be. I understand also by reading the article shown bellow that oil made for wetclutch should have standard JASO MA. Please read bellow:

Copy/Paste fra https://en.wikipedia.org/wiki/Motor_oil

JASO[edit]
The Japanese Automotive Standards Organization (JASO) has created their own set of performance and quality standards for petrol engines of Japanese origin.

For four-stroke gasoline engines, the JASO T904 standard is used, and is particularly relevant to motorcycle engines. The JASO T904-MA and MA2 standards are designed to distinguish oils that are approved for wet clutch use, with MA2 lubricants delivering higher friction performance. The JASO T904-MB standard denotes oils not suitable for wet clutch use, and are therefore used in scooters equipped with continuously variable transmissions. The addition of friction modifiers to JASO MB oils can contribute to greater fuel economy in these applications.[19]

For two-stroke gasoline engines, the JASO M345 (FA, FB, FC, FD) standard is used,[20] and this refers particularly to low ash, lubricity, detergency, low smoke and exhaust blocking.

These standards, especially JASO-MA (for motorcycles) and JASO-FC, are designed to address oil-requirement issues not addressed by the API service categories. One element of the JASO-MA standard is a friction test designed to determine suitability for wet clutch usage.[10][21] An oil that meets JASO-MA is considered appropriate for wet clutch operations. Oils marketed as motorcycle-specific will carry the JASO-MA label.

Not that many general mineralic 10W-40 og 20W-50 oil has the JASO MA approval. How important is it with JASO MA approval for oil used on old aircooled motors from the 75-80's produced in Japan..?

Hi Salaren,

I have read about the JASO Standards. But bying oil here in Germany, you will not find anything about JASO on the bottle. I think, it does not matter to drive an old japanese bike or german or italian or what else. The used materials in construction were almost the same. So the introduction for oil using is also almost the same: for classic bikes you find in german documents mostly 20W50 or sometimes 10W40 , depending of the using zone/temperature.

You cannot really do anything wrong with this mentioned oil for motor and clutch. So, don´t worry to much about it.

Cheers, Ralf

Thanks a lot Ralf. I agree with you, just try to make it simple. I will use classic mineralic oil but since the JASO standard are mentioned I just share with you the oil I filled on alle my Kawasakis Twins(400 and the 750) which is this one http://www.biltema.no/no/Bil---MC/MC/Ol ... 000022966/. This spring I replaced the oil filters and filled new fresh oil. ref. link above and have been driving approx. 1000km on each bice so far this year. So far it has been working well but I recently discovered that the z400 Twin motors needed around 2dl refill which I think is normal consumption, agree..? I therefore wonder if I should refil with a standard 20W-50 oil instead and see if the oil consumption reduces.

However, when you read the oil spec. on the link above you will see that this oil is classified within the JASO MA standard and should be suitable even for the older MC motors. You can buy this oil in Denmark as Biltema also have warehouses there.

Just wanna share information with you guys and I hope I am not doing a mistake that I filled this oil on my beatiful 1982 Kawasakis. Thanks a lot for all help so far.

Hello Salaren,

thank you for your tip. JASO is of course not wrong, because the Standard recognizes the clutch specifications. But your mentioned oil is semi-synthetic, and that seems a little bit tricky (not only the consumption). That´s the reason why mineralic oil is preferred for classic bikes.

Bye, Ralf