I was in my local motor factors yesterday and asked if I could buy a gallon of 10/40 engine oil. The guy asked (as he knows me) whether it was for my classic Mercedes as he had some oil specifically for classic cars. I answered that it was for my newly built KZ1300, and he said you can't use modern car oil in motorcycles with wet clutches. He said nowadays all car oils have friction inhibitors...?? And these don't go with wet clutches.
.... erm.... about six months ago I dropped at least a litre of ordinary 10/40 into my Kz1000P and that seems to go OK....
Can anyone confirm/deny this and explain? Do I need to 'rescue' my Kz1000P and see where I can find the right oil for both bikes?
You need to use a motor oil with JASO MA spec. It's specifically for engines which use the same oil on the engines with wet clutches in the same sump. Rotella T6 is a favorite since it also has a higher Zinc content and meets JASO MA.
My 2 cents
You need 10W /40 Semi Synthetic motorcycle oil and it must be for wet clutches.
If you want high quality oil at a very good price, then see Smith and Allan which is basically Shell Oil in their own carton..........but at half the price !
I have used it in every bike I have owned for the past 20 years and its superb.
McBoney wrote: So the guy was right and I need to drain my Kz1000P?
I probably would just to be safe for the mere cost of 5 liters of oil, but if the clutch is not slipping, you could get away with it.
Can't remember why, but i spent about 30 hours researching oil and how it's made just to get a fundamental understanding of how /why it's made.
Base Stock- varying grades of base stock with different natural viscosity. Ever wonder why when doing a cold oil change, some oils come out thick as molasses and others come out thin as water? Chances are it's the base stock before the modifiers were put in. Some base stock has a high viscosity and some a low viscosity. Viscosity modifiers are put in to alter the viscosity at different operating temperatures.
Detergent packages- Every oil manufacturer has their own secret recipe. Mixing different brands and different types within a brand can really mess up the detergent package.
Acid neutralizers to combat combustion by products- Vary by manufacturer. Not necessarily all are compatible. They alter the PH level in the oil
Friction modifiers- So many different ones and not all are compatible with each other. We're taking on a molecular level.
In a pinch and you're down a quart, better to top up than run with low oil level. Stuck midway on a trip, get what you can. Stuck at home, stay at home until you can get the equivalent oil to what you put in. I run Rotella T6 10W40 in my F250 with a 6.7 diesel since the Rotella T is the best diesel oil out there. I used to run it in the bikes because it's JASO MA certified and if I have the diesel here already, I always have Rotella T6 for everything except the Lincoln SUV since it wants 5W30.