Too bad I am not discussing anything. I am just saying what I do and that I don't care what others have to say about engine oils.

Good try, thou.

 

1. Our little thumpers work pretty hard at highway speeds compared to a car.
2. The KLX uses the same oil for the motor and for the trans while cars have separate oil. Gear oil is usually much thicker.
3. The clutch disk sits in the oil. The friction surfaces that wear all goes into the oil.
4. It only takes 1.5 quarts of oil.

Now choose your brand, viscosity, and change interval. How hard can it be?

 

While the clutch isn't great for the oil environment, I remember seeing where an oil engineer stated that the tranny gears are harder on an engine motor oil than just about anything else. Something about molecule chain shearing at the microscopic level. Just repeating something I read.

 

I've read the same somewhere too. That's why I change oil often. I can change dino oil 2-3 times for the cost of 1 synthetic change (not including filter). I've never run synthetic and have never lost an engine. "Synthetic" also doesn't mean 100% synthetic now a days as some may assume. I do know my oil is closer to "clean" than closer to "dirty" most of the time which I believe has more to do with longevity than the brand or type. The more you read the more annoyed you get. Every now and then you'll glean some good info, but I don't have time to make a religion out of it.

 

It is better to have oil in it, clean/dirty/whatever. The more miles spent at operating temperature, the less you need to change it.
I don't get everyone using synthetic oil, then buy a new vehicle every 5 years or sooner. Maybe if your going to keep it for 30 years it would be worth it. You will never wear it out using regular oil, hello!

 

As long as it doesn't have the friction modifiers in it you are fine. If you look on the doughnut/star on the bottle along the bottom and it says "Energy Conserving" it has the friction modifiers in it that will eventually load up the clutch and cause it to slip.

I used full synthetic without friction modifiers in both my LTZ400 and klx with absolutely no problems at all.

 

If I understand the oil numbers a 0w-30 and straight 30 weight will be equally thick at operating temperature. So the only time that the W number means anything is at cold start. Even in cold weather, your oil is hot enough to be out of the W range.

Concentrate on the second number as that is what your engine will be living in. 10w-40 like the manual says or 15w 40 diesel oil or even the really cool 5w40 synthetic diesel oil I use in my truck should all be equally liquid at operating temp. If I have to cold start the bike in freezing temps, I want the 5w40 for its cold flow characteristics which will allow easier cranking, faster cranking, and faster lube of bearings.

 

The "W" really does stand for "Winter". They did that when multi-vicosity oils first started coming out a LONG, LONG time ago. It just made it simple to understand.

Since Castrol beat Mobil 1 in a lawsuit a generation ago, MOST oils labeled as "synthetic" are actually Group III oils that have undergone severe hydrocracking. The term "synthetic" is now a marketing term, not a scientific term, AND, depending upon the additive pack, some non-synthetics actually perform better in real-world engines.

One other thing to consider: MOST oils don't use PPD (Pour Point Depressants), rather, they use Viscosity Improvers. What this means is that an oil listed as a 15W40 is really a 15 weight oil with Viscosity Improvers that are long-chained molecules, which make the 15 weight oil act like a 40 weight oil as the oil is heated up to operating temps, because these long-chained molecules "unwind" as they are heated...and that's how they make the oil act like a straight, true 40 weight oil acts at 200 degrees. As you can imagine, these long-chained molecules are somewhat vulnerable to "shearing". The more they shear, the closer to the base 15 weight oil the solution becomes. THEREFORE, a 5W40 is usually more prone to shearing to a 30 weight more quickly than a 15w40 will shear to a 30 weight. SO, if you don't ride in below freezing temps, use a higher base oil weight rather than a lower base oil weight, and your oil will generally last longer before it loses a viscosity range due to shearing. There are some exceptions, and there are some oils that use PPD's, so, the base oil isn't really as low as the number just before the "W"...but, these are generally "boutique" oils with fairly high price tags.

I have spent hundreds of dollars on Used Oil Analysis, and this is what I do, in case you might care: I save my money, use something like Rotella 15w40 or most any brand-name 20w50, and change it before I hit 1500 miles. I leave the filter in for at least two oil changes...they get more efficient as they are seasoned, and oil good quality oil filters EASILY last 3000 miles in these bikes with no increase in insoluables on the UOA.

 

wow, great post. thanks for the info!

 

I don't know...I've run those "Energy Conserving" oils in several of my bikes that I ran up a lot of miles with and never encountered a clutch issue. I've seen this statement presented as fact from lots of folks, but I never had a problem. Most of my experience was with different types of Mobil 1 that had this designation. I would even swap between versions that didn't have the friction modifiers and back again...no clutch problems. I'm thinking this is another myth in the long history of oil threads.