may have made a big mistake with oil selection

22 replies to this topic
  • grayracer513

Posted May 06, 2005 - 06:43 AM


Cause i dont have a bike shop here in town.....I guess reading is not a concept you understand :)

I don't buy the Mobil 1 MX4T that I use from a motorcycle shop. If I did, I would have to pay $9/qt, and that would be wrong.

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  • grayracer513

Posted May 06, 2005 - 07:07 AM


If you check your manual, you'll see that if you're riding above 40F (most do!) or higher,they recommend 20W40 Yamalube (or non friction modified 20W40 motor oil). The 20 in the 20W40 is the important part. It means it's as thick as 20W would be when it's cold and as thick as 40W would be when it's hot.

If you check the other edge of the same chart, you'll see that any 40 weight multigrade is suitable for use up to the same 114 degrees ambient temperature regardless of its "winter" (W) grading. There's nothing wrong with a 10W-40 necessarily, and in fact, a lot of the better full synthetics behave as a 10W-40 with no viscosity index improvers at all. With a non-synthetic multigrade, there are legitimate concerns about viscosity break down (shear stability). There is no difference in the viscosity of a 10w-40 and a 20w-40, or even a straight 40 weight, at 212 degrees F. The 10 is only thinner on initial start up, and that can be a much greater advantage than a disadvantage, since the oil filter's bypass valve is less likely to open, and oil is delivered to the entire lube system as freely as if it were much warmer.

I use Mobil 1 MX4T 10w-40. Before that, I used Golden Spectro 4 10w-40, and several people I know are using Shell Rotella T Syn 5w-40, and have been for a long time.

As far as Mobil 1 15w-50, there are at least two now, and the synthetic has been changed considerably, so check into it before using it.

If you thought you'd be flamed for recommending synthetics, you apparently haven't read many of the 18 zillion oil threads this site has generated. And BTW, I broke my 250F rebuild in on MX4T full synthetic. It hasn't used a drop since its 3rd hour. :)

  • devilsslide

Posted May 06, 2005 - 08:13 AM


Yep, Mobil 1 MX4T is the best stuff around.... MOBIL 1 WEB PAGE

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