Kawioops, you are right that the engine oil you choose is not the cause of a breakdown or a part failure, but if you run your KLR without any oil for just a few minutes you will more than understand the reason for the oil, and hopefully begin to understand the reasoning for making and using better oil.
The old ignorant saying that "oil is oil" is exactly that, old and ignorant.
There are a few problems I see and keep seeing. They are #1 that most people just dont pay attention to whats going on with their engine. #2 Most people simply will not read a bonafide certified test and accept the results. #3 Most will dump whatever oil their buddy, Dad, or Kwik Lube Mechanic said is the best without any info to back up the claims. Last but not least #4 there is a large group of people who will simply use the cheapest oil they can find to dump into their multi thousand dollar investment vehicle. Consequently these seem to be the same people who cry foul the loudest about a particular brand vehicle and its workmanship when it fails.
The simple fact of the matter is their is a best of everythig that performs. Performance is how you measure these things, and the one that performs best is the best. You wouldnt judge an oil by the color of the bottle it comes in, just as you wouldnt pick the fastest car by the color of its paint.
Putting all performance issues between oil and engine aside, an engine and its parts will eventually wear out despite brand, workmanship, or tech using even the BEST oil.
A big part of an engine lubricants job is to fend off this inevitable demise for as long as possible. There are many ways this can be achieved, but 2 stand out to me. #1 Reduce friction. Without friction our engines would run forever, consequently if friction didnt exist we really wouldnt need the engines too begin with. #2 Resist breaking down. The ability for an engine oil to resist shear and to remain in grade is vital to #1.
Case in point:
http://www.amsoil.com/testimonials/409000.aspx
409,000 miles without an oil change!
Findings
The engine showed light to moderate wear throughout, just as an engine in similar service and lubricated with conventional oil changed at 15,000- to 20,000-mile intervals would show. In fact, according to the engine rater the parts he examined cylinder liners, pistons, rings, bearings, valve train components could have been put right back in the engine and would have continued to provide the good, dependable service they had provided all along after 409,000 miles without an oil change!
Probably 95 percent of the crosshatching is still in the liners. No scuffing, no cavitation in the liners. The liners could go back in the condition theyre in.
The pins show no wear at all. The piston crowns and lands show a normal amount of carbon. The skirts are very clean with a few fine vertical lines.
The rings are very, very good. All the rings are free. None are broken. No plugging whatsoever in the oil rings.
Mainbearings
Light wear. They compare to [those in] an engine that had 15,000- to 20,000-mile [petroleum] oil and filter changes.
Rod bearings
Minimal wear. These, too, compare to [those in] an engine that had 15,000- to 20,000-mile [petroleum] oil and filter changes.
All these facts were the conclusions of an independant engine rater.
No other company I know of publishes tests like these for all of us too see. These results year after year, time after time simply can not be ignored by someone who REALLY wants too use the best oil they can to protect their investment.
I dont really care what oil anyone else uses. Really. It doesnt cost me a cent when your new truck needs and engine rebuild before 100,000 miles or your scooter is toast before 50,000. However I feel it is my duty to help out friends with common interests so I try to posts the info and experience I have in order for everyone to have the good fortune Ive had for the last ten years.
Ive built and rebuilt many engines from many different vehicles. From weedeaters, chainsaws, and lawn mowers, 2stroke outboards, single and multi cylinder 2 and 4 stroke motorcyle engines, and high HP V-8's from the big 3. Ive seen the effects of just about every kinda mechanical breakdown an engine can face while tinkering in my garage. There are few things that stand out though.
One of which is how paper thin my rod and main bearings were when I rebuilt the family suburban's smallblock 350 years ago with only 230,000 miles on it. The majority of which my wife and I put on it, and through which I maintained it meticulously, never running over the 3,000 mile mark before it got a new batch of Penzoil 10/40. This truck was not a race car, never hot rodded, never driven hard. It was a daily driver for my wife and a vaction vehicle for the whole family. It was a freakin custom Cowboy Conversion Suburban for cryin outloud.

Yet the rod bearings looked as if I had ran WD-40 in it for the last 100K. Since then Ive seen many like it. Between that example and the sludged up heads on many of the other engines Ive built who were run with a premium mineral oil I have too say the comparisons to the ones Ive tore down that had been running either factory synthetic fluids or by owners choice synthetics were very very different animals. The failure point on my old truck was the oil pump shaft by the way. Right at start up one winter morning. Soon as I heard the knock I shut'er down. That sound is akin to fingernails on a chalkboard through an amplifier when you hear it coming from your only vehicle, ya got 20 bucks in your pocket, 2 kids ta feed, and your lookin for work cause your steady job barley makes the bills. Fireman get payed the big bucks! :lol: Seems penzoil 10/40 flows like honey in a freezer at 40F. I live in West Texas where winter is very mild. According to both Penzoil's data and Chevy a 10/40 should not flow that poorly at such a moderate temp, but thats mineral oil for ya.
Ive seen both sides first hand. I always tell people not too believe the hype, but to do a few tests themselves. Few ever do. Seems some humans would rather argue using hersey as proof than too actually find the proof themselves. Ive done many tests on oil in my garage just to see for myself if oil companies claims and numbers were the truth. Some were, some werent.
I can say from experience, testing, third party documentation, and I witness proof that PAO or Ester based, 100% synthetic oil is better at reducing friction and resists breaking down better than ANY mineral/conventional oil. Those are facts. That other stuff was just fluff.
Disclaimer:
I'm not a mechanic by trade. Workin on cars, trucks, and sickles is a hobby Ive had since I was a kid in my Dads garage, and I have made a little money doing it. I make an effort to be informed about as many things inthe field as I can, and I have good sources since most of my family are either mechanics, engineers, or builders for Ford. With my brother being a traitor being ASE Certified for Honda, Toyota,and currently certified and works as a Lexus mechanic. I decided to be a Fireman and do the wrenching as a hobby.
Edit:
Ham, I didnt see your post till I had written mine. Good info, I agree except for the temperature controlled KLR part.
Daniel