Yet another "oil light" discussion:

[Semi239]

One thing I don't read about is engines blowing up on a regular basis due to lubrication failure.

Beautifully written Mr Max. I think you're dead on. If this o-ring was as problematic as some thought, it would be a known issue at Yamaha that they should have addressed. That reminds me of the starter clutch that they seemingly knew about but chose not to address for the entirety of gen 1 production. I want to believe that the starter clutch being ancillary in nature caused them to disregard it as a maintenance item. Oil starvation on the other hand is not maintenance-related, it can cause total engine failure. And by that logic, they would've fixed it if it was the o-ring was causing oil starvation/engine failure on a large scale(as you said).

That said, it's an easily preventable point of failure and I'll replace the o-ring for peace of mind. I love a cheap fix that brings more confidence in my machine!

 

[Bill Seward]

I never had a problem with my engine oiling over the 135,000 miles I've ridden it. If the O ring has popped out, it hasn't affected my engine, so far. Of course, I "ride it right", and don't beat on the machine enough to turn on the oil light. Beating on the bike and bragging about seeing the oil light, in my opinion, is just plain stupid.

 

[MaxMidnight]

I put an oil pressure gauge on mine just for the peace of mind. Pressure is higher (60 - 70 psi ) on start up and drops to ( 15-20 psi) after warm-up. I have been told this is normal.

Correct and IMO why the O ring can pop if there is sudden acceleration before the oil is up to temperature.

I have often wondered if Yamaha designed the pipes to allow some flex when there is a sudden increase in oil pressure. It would have been possible to make it a rigid fixing but they chose not to?

Theories on my desk first thing Monday morning please.

 

[one2dmax]

I agree that there are likely thousands of these out there that have displaced orings. BUT, there are tens of thousands of these that never see redline too. You WILL have reduced oiling with it displaced. BUT, the engine does not need a huge amount of oiling to run a normal life. But, if you are running it hard all the time you will have more failures then people not running it as hard.
I will say that every engine I get in here that has a problem with trans or spun bearing have that issue. But, I don;'t get many in here that run just fine that i tear down either to see what or what isn't in place.

If you are going to run the engine at 80% of it's max RPM then you are going to blow it up on a pretty regular basis.

 

[Jack Hammer]

Why would anyone rely on "what might be" or what is so called "common knowledge ?" Your bike is an individual machine. If you feel worried about something and you trust your own instincts, go do it. Lot's of info to be found on this site but it doesn't make it true what it comes to your bike necessarily.