phosphorus question

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Being a 40, it doesn't have to comply to the limits that 30 and below have, due to the (generally accepted) lower consumption and volatility of 40 and above oils.
Got it, thank you. Do you think that 0,144% phosphorus is enough? How are generally seen Mobil products here? thanks, DH
Originally Posted By: dharry
Do you think that 0,144% phosphorus is enough?
Enough for what? What is your application (car/engine/year/modifications, etc.)? It is certainly enough for any modern engine.
To be honest, I use it in my motorcycle :-) I was asking this because last time I used an API SM semisinthetic 10w40 car oil, and the gear lever became suddenly hard to push (never used the SM before, and never had such a problem), so I changed back to an API SL (the Mobil 2000 x1), and everything went back all right. I thought it was because of the lower phosphorus content of the API SM, but now I think it must be something else... I'm planning to stick with the Mobil 2000, what do you think about this oil? thanks, DH
What motorcycle? Does it have a shared sump (wet cluch)? Some oils may have significant amounts of friction modifiers and that's something that you typically want to avoid in a wet clutch as it may cause slipping; however, I'm not sure how it would cause the gear lever to become hard to push. According to your bike's manufacturer, what specifications should the oil meet?
the bike is a 2007 suzuki bandit 650, the manual recommends 10w40, api sf-sg or sh-sj with jaso ma. It has a shared sump, but on my bikes I've always used ordinary car oil (both semisynth and full synth) with no problem, even at very high mileages. I was asking here because we're speaking of car oils :-) thanks, DH
I would probably stick to JASO MA rated oils then. Alternatively, people have had good luck running HDEO (heavy duty diesel oils) in their shared sump bikes. We have a motorcycle subforum where you can find many past threads on this subject. We don't have this particular Mobil oil available in the US, so I can't really comment. Judging by the somewhat low SA content, it looks like the additive pack is somewhat weak, but it does meet API SL and ACEA A3, so I think it would be fine. I guess the only one way to find out for sure is to try it.
An an anti-wear additive, you should have > than about 1500 ppm (0.15%) of zinc and 1350 ppm (0.135%) of phosphorus tied up in the ZDDP molecule. I would say that's about right for a motorcycle engine. Looks like a good semi-synthetic. As others have stated, the friction modification might cause clutch slip depending on how much FM the manf. added and whether you have a wet clutch or dry clutch.
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