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10W-40 fully syn engine oil?

Discussion in 'Maintenance and Servicing' started by highon2str, Jul 21, 2013.

  1. [​IMG]

    Bought a 5L bottle from SCA and yet to use it on the SV, just wondering if anyone's used this with success on their ride? :)

    According to the website:

    "Everyday Full Synthetic 10W-40 is suitable for use in passenger cars, 4WDs, motorcycles (including those with wet clutch assemblies) & light commercial vehicles"
  2. #2 phil01, Jul 21, 2013
    Last edited: Jul 21, 2013
    pretty sure its no good at night
  3. No good at night?
  4. You've had nearly an hour to think about it - got it yet?
  5. Have always used thier oils in my cars, and have had no dramas.. currently use hpr5 in my vzII, have not tried thier oil in the motorbikes though.. Watching with interest..

    Currently use Castrol race oil in BMW as recommended by BMW

    Race bike GSXR600 gets Motul 10w40 semi synth
  6. It is JASO MA rated so no problem, but only for every day!
  7. I heard it settles out if you don't start the bike up each day.
  8. #8 Tim500, Aug 12, 2014
    Last edited by a moderator: Aug 13, 2014
    Hi everyone ,can anyone tell me if its harmful to put 10w/40 in your bike instead of 10w/30 which is specified in my owners manual.Just had the first 1000k service and the mechanic has added 10w/40 instead of 10w/30 and I want to know if the thicker oil will be harmful for my Honda CB500X.Any help much appreciated

    Discussion topic has no relevance to:

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    Thread will be moved this time. In future please read the forum descriptions so you know where to ask your Q.

  9. No, in Australia it is common to use a higher temperature rated oil. The difference in viscosity is small enough to make no difference.
  10. Interestingly Honda branded oil is supplied in 10w30, even in the oil change kits, and as pointed out it's what is recommended in manuals. I agree with you and use 10w40, but I do wonder why Honda does this.
  11. Maybe they are specifying the average for a world delivery. In colder climates the viscosity at sub 100 degrees may be too gluggy. A bit slicker in gear changes perhaps?

    Don't really know, just a guess. :)
  12. Hmm. But how well does a 10w30 oil hold up during the Australian summer with 30+ degree days?
  13. I think this was more of an issue in the days of air cooled bikes. Modern liquid cooled bikes with their thermal management systems you can be reasonably assured, provided nothing goes wrong, that their upper temp limit will be limited to 100 - 120.
  14. the 10W portion means it's good for use as low as -20 degrees. So it won't do any harm even in the coldest part of Aus. 15W is good for -15 and 20W is good for -10 degrees. So all are fine in Australian bikes.

    the 40 means it's good up to 40 degrees ambient. This is why I prefer to use 40 over 30 in all but winter in Aus.

    Even with water cooled bikes, their oil temperature isn't as well controlled as water cooled cars. This is because all the cooling and heating is done in a much smaller and confined space.

    So 10W-40 is a good oil for Aus, but not necessary in winter.
  15. You were going so well then you crashed and burned!

    Oil viscosity ratings are not temperatures!

    The 10W is to do with the ability of the oil to flow and therefore lubricate at low temperatures, so you are somewhat correct with that part.

    The 40 has absolutely no correlation with temperature. This is an SAE grade (SAE 40) and is a rating of the oil viscosity at 100 degrees C (near typical running temperature). This means its viscosity at 100.0 degrees C is somewhere between 12.50 and 16.29 centistokes. Which is just a measurement of how quickly the oil flows through a small tube.

    I don't necessarily agree with putting a 10W-40 in an engine with a manufacturer recommendation of 10W-30. This assumes the running temperature is higher than the manufacturer expected, however with thermostats and decent cooling systems the running temp in Australia (except on rare days) is not normally any higher than anywhere else.

    The manufacturer will recommend a viscosity based on engine tolerances and nuances, so it is important to use the correct viscosity. In saying that, I don't think using 10W-40 instead of 10W-30 would cause damage.

    Source: I'm a chemist working for an oil testing laboratory
    • Informative Informative x 1
  16. Thanks for the info. I was just basing my information on the commonly available oil range sheets, where they do correlate vicosity to operating temperatures.


    As to bike running temp, with bikes there are really 2-3 different scenarios. With a car I'd absolutly agree with you, but many bikes are still air cooled or air/oil cooled. These bikes definatly run hotter in an Australian summer than they ever do in Japan, Europe and most of North America.

    The above chart is for an oil/air cooled DR650 and as you can see 10W-30 would not be good in Australain summer.

    I'm even of the opinion that water cooled bikes are not much better at controlling temperature at consistant level, like cars can, due to fairings, small fans, low coolant volumes, etc.
  17. A lot of charts show 10w-30 as suitable up to 30 degrees Celsius ambient. Why? And what happens to it on a 35 degree day, does it become too thin?
  18. If the 35 degree day corresponds to a significant increase in running temperature, then yes, it could become too thin.

    The "30" really doesn't have anything to do with the temperature of the day, after all this is an SAE rating which comes from America, the land of fahrenheit!

    Many manufacturers recommend slightly different grades for winter and summer, but with new bikes and synthetic multigrade oils it isn't necessary.

    Good point ibast, I really was only considering water-cooled engines.
    • Like Like x 1