SportsterDoc_imp said:
InMy Moto Guzzi had a separate sump for the transmission and also had a dry clutch; but I did not use automotive oil to lubricate the engine for at least two reasons:
1. There are additives / detergents in automotive oils that may not be good for a motorcycle engine.
2. Automotive oils have less zddp.
Is there a difference between motorcycle and scooter engine oil?
Same with my Can-Am Ryker. It has a separate transmission sump for forward-reverse (ratios change by CVT) and no wet clutch.
Also, 10W60, as specified for the Moto Guzzi and 10W50, as needed for the Ryker at temps above 104 F may be difficult to find an automotive oils.
As for 0W20 or even 5W20 oils, there are many automotive manufacturers having serious oil consumption issues with their engines for which of these weight of oils have been specified.
Changing oil on an air-cooled motorcycle at 3,000 miles can be beneficial.
Using pure synthetic oil is most likely beneficial.
Using oil filter without a bypass valve is questionable.
Using automotive oil to save a few dollars may be costly in the long run.
Sportster Doc, I read the Rymax link you sent. Thanks for the link. Here is my commentary.
They point to two reasons that point to the formulation differences between car and bike that their warnings are based on:
1) Car oils have friction modifiers
2) Car oils have detergents
So, looking back in this thread I pointed to the API symbol, and according to my understanding, you do not want to use car oils that have these. I have personally had to change my clutch plates after using car oils with friction modifiers that caused my friction plates to slip. I suppose Rymax might call this "major motorcycle damage". So, you do not need to convince me on this one. That clutch pack change was on a Honda '88 Hawk GT I had two decades ago. That was a PITA! Ever since then, and having learned my lesson, I have never used car oil with friction modifiers. You must avoid any oil that says "Energy Conserving, or Resource Conserving". It is my understanding, and also my experience in the two decades since (and many, many oil changes on many, many brands and engine configurations: twins, inline 4's, V-4's). I have NEVER had a problem since. I would consider that last statement as anecdotal evidence from one person on a board.....Some modifier ingredients could include Teflon. There are also likely others I cannot list or name as there are many proprietary formulations that are not divulged. In short, don't use them. Their warning says "Using the wrong oil can seriously damage your motorcycle." If you use synthetic oil (w/o friction modifiers that could impact your clutch), then both motor and gear box should be happy as they are well lubed and protected from wear.
The second detergents..."that could result in formulation of deposits on piston crowns and as well as the valve train".
Ahem. I am sorry on this one. As far as I know, there is nothing inherently different between car and motorcycle pistons or valvetrains, or inherently different in their basic Internal Combustion Engine construction. If I am wrong here, please tell me where. Seriously, I don't know everything and could be educated. I mean that respectfully.
There are some m/c specific designs you generally do not see in cars, like the desmodomic valve actuation system used by Ducati, or in cars (mostly abandoned push rod actuation....but still used by Harley). Maybe someone can explain to me the inherent significant difference in a piston designed for use for a car, and one for a bike. They all run the gamut in terms of compression ratios, but most now in either category are made of light-weight alloys with coated cylinders. Many in either have variable valve timing schemes. Most have chain driven overhead cams for valve actuation in either.
The warning on detergents "these could result in the formation of deposits on the piston crowns as well as the valve train. Because detergents are the main cause of pressure build up, this will cause perforation and burning on the components".
I am sorry and am going to call BS on this one and point it to marketing. I will call "true" to the friction modifiers. Don't use oil that has them. So detergents don't cause damage to car piston crowns and valves, but they do on bikes? Also, I thought the point of detergents was to avoid build up on components. I look at it like this. If deposits form on pistons, then they can heat and cause preignition resulting in damage. But I thought detergents help prevent this. I call this marketing with frightening statements to corral us. That's me though and all IMHO.
Interestingly, on the Guzzi threads, some there are lamenting the use of Motul and other Racing oils because of their lack of detergents!
In terms of Zinc dialkyldithiophosphate (ZDDP), zinc and phosphorus used as an anti-wear agent, those have been phased out of motor oil formulations in recent years because the zinc and phosphorus found in ZDDP can negatively affect catalytic converters. From Amsoil "classic-car owners having older vehicles with flat-tappet camshafts and, in particular, engines that include high-tension valve springs or other modifications that create high contact pressures, can suffer premature wear due to reduced ZDDP levels". So those guys want that.
TO ME, don't buy oils with the wrong API symbol. I used photos to show you (MY understanding) of a right one and wrong one.
One last wrt to your 10W60. Wow, that is oddball. wildguzzi and guzzitech have lots on that. If you are worried about shear taking down the weight to 40W-50W in only 1-2K miles, I might just change more often. The Mobil-1 20W50 is $4/q. That oddball 60W is $15/q! What is the recommended change interval? How much effort is it to do it?
In the Wildguzzi thread on the 10W60, SmithSwede says:
"Great psychological analysis of oil threads! I'd add one other point---it is an interesting psychological fact that people worry so much about oil, and "protecting their engine," when the vast majority of them don't get anywhere close to using the normal service life of the machine.
If you are only going to run the bike 10 to 30,000 miles before you sell it for something else, it probably doesn't matter that much what oil you use if it's decent quality and at least close to the recommended specification. For these people, the engine isn't going to wear out in any meaningful sense---you are going to divorce it long before you could perceive any differences between Oil A versus Oil B.
Seems to me that the only people who should rationally obsess about the subtle nuances of tribology are people who really do plan to run the engine 200,000, 300,000, or more miles. There probably are a few such people on a Guzzi forum; not so much on a Ducati race bike forum. "
LOL.
One maybe last post on this very old and possibly tired topic.
In the end, it may be best to just do whatever it is that gives you comfort you are doing the best job possible to protect your investment (ahem, depreciating asset) and what makes you sleep well at night.
Some of the stuff you see from me is based on a fact that I am an extremely frugal person....in a sense, in that I like to do things myself and save money (including things like buying cheap sets of quality tires at sale prices in Winter, and mounting/balancing them myself), and also trust in my own mechanical expertise, that there are a great number of fine details I will take that a paid mechanic will not. Case in point is cleaning my case with a brush till new, no paid mechanic will do. I do this when addressing my brakes, with everything cleaned and freshly lubed, whereas a paid mechanic will just slap in the new pads. I extend this mindset everywhere in my existence, to building my own house (bomb shelter), to working on my cars, to fixing anything. With the money saved, I am "free" to splurge on the things that make my hobbies have more satisfaction and fun. Standing back and looking at the modification to my CB knowing it was done right and the least cost possible is a way to derive tremendous satisfaction to me.
As to oil, as was said earlier, and it is like debating religion, "has the debate changed anyone's mind yet?"
