The International CBX Owners Association

This is not intended to be the start of another oil thread. I had a business meeting with an Exxon engineer/chemist and as a little side excursion we talked about oils as he was looking at my eclectic collection of motorcycles. I just want to share some of the information he provided which I consider very useful for myself. You do whatever you think of with it. I may answer questions regarding the facts, if I can, but I will not engage in any kind of argument or discussion about what is right and what may be wrong. To me the source is a capacity in his field and I take his word for it.
Please note that we mainly talked about Mobil1 synthetic oils.
Ever so often the EPA reviews components and additives in motor oils and recommends certain limits to be adhered to. The API – American Petroleum Institute – accommodates the request by grading oils and issuing specifications and standards usually identified by a two-letter designation. The current and latest of these designations is SN, although most oils available on the shelf are still SM and some are even SL.
You will have a hard time finding any major brand automotive oil that still carries SF,SG,SH or SJ designation.
The key issue here, in a nutshell, is the presence of phosphorous (P) and zinc (Zn) as anti-wear additives as they negatively affect the catalytic converter in automobiles and sulfur, which causes corrosion.

The interesting thing, however, is that the recommendation for such limits of, for example 8oo ppm of P does only apply to oils with a viscosity rating of 0W-20 through 10W-30. Oils with ratings of XW-40 or higher have no such limits.
There is quite a bit more to that, but in order to concentrate on what was important for me, we focused on the question what Mobil1 synthetic oils I should use in what motorcycle.
Motorcycles have clutches to be considered and the fact that the transmission gears accelerate the shearing process and degradation of the oil. Also many motorcycles have flat tappets
1. BMWs with separate engine oil. Does not come into contact with clutch or transmission gears.
Mobil 1 15W-50. Recommended for performance vehicles, higher ambient temperatures and (important!) flat tapped applications. 1200 ppm of P and 1300 ppm of Zn! Excellent corrosion protection to counteract the negative effect of sulfur.
2. Other bikes with “unit” powerplant., e.g. all my Hondas and Kawasakis and the new BMW K bike.
Mobil1 Racing 4T 10W-40. For motorcycles where clutch lubrication is important. 1600 ppm P and 1700ppm Zn. This oil still has a SJ/SH rating, but also complies with SM as it was exempt due to the fact that it is heavier.
3. The HDs could use 15W50, but of course there is Mobil1 V-Twin 20W-50, supposedly formulated for V-Twin engines and this oil has a SG,SH designation. Same P and Zn content as the 4T 10W-40
4. Finally for the Ducatis, I stay with Agip Racing 4T, SAE 20W-50 and 10W-60 , full synthetics, which are API SG. The reason being mainly that I get a killer price for that stuff.

The gentleman from Exxon left me a complete data sheet for all the Mobil1 Oils. If anybody has a specific question about an oil, pm or e-mail me.

10 years have passed since you logged this post EMS and high performance air cooled engines are very much yesterday's tech. The oil companies have moved on so I wonder if your preferences for oil in the CBX have changed?

I use Penrite 10W60 in the Lump. It is a full synthetic PAO ester oil rated JASO MA. James Fisher uses Valvoline 20W50 in his race bike, a full mineral oil rated JASO MA2. These oils are expensive and there are compromises with the wet clutch.

Heat or rather too much heat is a problem for CBX's. Roly Skate reckons his Beast used to regularly exceed 280 C at which point most oils start to oxidise. Lionel Brancquardt converted his 20,000 rpm CBX to a dry clutch in an effort to deal with the issue of oil degradation.

What are your thoughts on the best oils on the market for CBX's today?

Thanks, Mike. Just plain good info to share. And, as you said, not to begin some 'heated' discussion. Just good info.

Good to know as I just put in Mobil1 4T 10-40 based on an extensive hunt through all the oil threads....

The reason I have raised this subject of oil is because oils like fuels have changed dramatically since the CBX came to market.

My Prolink manual recommends an SAE 10W40 oil however a few things about the CBX make it particularly important to choose the right oil. First and most obviously it is a large multi cylinder air cooled engine. This means temperature control relies on air/oil cooling which is more difficult to control than in a liquid cooled motor. Even with liquid cooling there can be problems as Kawasaki discovered with their big 6. They never did resolve the overheating issues with that bike.

Hondas have always run high pressure oil pumps. The Prolink pumps at over 70 psi so you also need to take account of this when you are purchasing the oil filter that must be high flow. The higher pressure circulates the oil more effectively aiding the cooling and the design of the plumbing concentrates oil flow in critical heat prone areas. The CBX is pretty good in this regard but they can still get very hot when the available performance is being fully used or just on a hot day in slow moving traffic for example.

Finally, oils have changed a lot since the 70's and 80's and most modern 10W40 oils use lots of additives to achieve the relatively wide viscosity range. There are downsides to this. There is a good description of the pros and cons here:-

https://www.upmpg.com/tech_articles/mot ... 0oil%20has.

Now I am not a chemist and after reading the above description you may appreciate why I raise the issue of the suitability of more modern oils for use in the CBX and why I choose to use a full synthetic PAO ester oil for racing. But I'm no expert on the subject and this does not necessarily answer the question of what are the best contemporary oils to use in a CBX roadster. This is why I would like to hear what others think about the contemporary choice of oils available to CBX owners.

Just a final point that I would like to reiterate. The 'hot oil' standard measurement for oil viscosity is 210 degrees.

The CBX can reach temperatures in excess of 280 degrees at which point many oils will break down.

By way of contrast a modern jet engine reaches temperatures in excess of 1600 degrees and the Nimonic turbine blades composed of single crystal nickel/chromium/tantalum/titanium and some other rare earth elements break down around 1400 degrees.

The actual process of forming these special crystals is a carefully guarded commercial secret but the whole thing still relies on incredibly precise plumbing to enable micron thin air cooling together with high stress oils. That oil technology is now in the market place.

Note that Shell Rotella T4 meets the JASO MA2 spec called for many m/c applications, including Honda. You all might find this link from AMSoil interesting: https://blog.amsoil.com/whats-the-diffe ... o-ma2-oil/

Thanks Larry, that is a good explanation.