Sorry guys, I can't help it - Lubrication Training 103 - Synthetics and Antiwear Agents
To the original question, mixing dino and synthetic is ok with any brand if you NEED to.
Not necessarily true...although generally OK. Without getting overly technical, there are lots of ways to make lubricants "synthetically", but you generally only want to use synthetic hydrocarbons for blending with mineral based hydrocarbons
PAO (Poly Alpha Olefin) are the most common synthetic, often co-blended with Diesters (Dibasic Acid Esters) to improve additive solvency. These blend just fine with mineral oils, and this is what you will usually see.
but other products are used to make synthetic oils, usually in NON engine oil applications, including:
Phospahate Esters (common in Fire Resistant Hydraulic Fluids)
Alkyl Benzene (Alkylated Aromatics) - fairly uncommon
Polyol Ester - FR fluids and aviation turbines
Poly Glycols - (common in compressor service)
There have been times when someone has used these other products to formulate engine oils. More common 15-20 years ago, but you do need to be careful.
Again, any PAO (with or without small amount of Diesters) blend with mineral oils just fine. So absolutely no concerns with Mobil 1.
Just some comments on blending, generally.
Avoid 50/50 blends (even with mineral oils) as this is where the most likely tendency for problems exist, expecially with anything that turns and mixes, and is exposed to heat. Since every oil you will ever use is fortified with some type of additive, the chemical balance CAN be upset. The most common problem we see is foaming, since you can make antifoam agents (which are really surface tension modifiers) using either acid or alkyline based technology. Add them together, and you can have a foaming problem.
On the other hand, reading Mobil1's spec page for comparing ZDDP levels for the different weight oils, it shows the BIKE oil has 1600ppm ZDDP, the 15-50 has 1200ppm, and the energy conserving type has 800ppm. Reading this, it would seem there is more than a slight difference between the Bike oil and the 15-50.
My math tells me that's a .04% difference between auto and motorcycle Mobil 1 formulations.
Chemically, this IS a huge change. The real question is how much zinc and phosphorous (ZDDP) is the right amount? ZDDP is an antiwear agent. Think of it like putting a thin carpet on the metal parts. When the asperities (high and low points) on a metal surface make contact, the additive takes the brunt of the impact, reducing the wear on the metal part. Since most metal parts are floating on a film of oil (hydrodynamic lubrication), the amount of impact should be relatively small, unless the loads are very high, and/or the speeds are low.
There is a case to be made that additional antiwear can reduce valve train wear, but I'm not sure that valve train wear is much of a concern in our Bandit engines (at least the 1200 & 600's). Beyond that, the extra ZDDP should assist in reducing tranny wear, but again, the jury's out as to how much of a good thing is necessary.
Engines that should benefit from extra antiwear include big air-cooled singles & twins (especially pushrod Harley's), or other high torque/low rpm applications, and these engines generally NEED higher viscosities as well. (ie 15W-50 or 20W-50)
Anyway, back to the debate. For those who want to read some more opinions, check out these threads:
http://forums.banditalley.net/index.php?topic=3835.0http://forums.banditalley.net/index.php?topic=4607.msg34061#msg34061http://forums.banditalley.net/index.php?topic=8263.msg62450#msg62450http://forums.banditalley.net/index.php?topic=8913.0
