Originally Posted By: Trav
New engine measurements and wear limits from Honda FSM. Over 200K km all lubricated parts within new specs using Starrett micrometers (digital and analog).
This engine was owned by me from 0km brand new in crate motorcycle for over 12 years, run on one brand and weight oil except for the break in and Honda oil filters with the exception of a few aftermarket filters when OE was not available.
Engine was totally disassembled for a stretched cam chain, cylinder and pistons removed and cases split. The engine routinely saw 12,000 rpm and high sustained speeds.
What experts? I have SAE access. No dispute oil with few particles will result in less wear but the question is where do the particles come from?
This particular engine is a rare and perfect example for this discussion, it was in the same hand its whole life, taken care of by someone who knew how to and did take care of it and it has a full OCI history.
Another point worth mentioning is this engine was very tight and well protected against stray air ingress and tight ventilation system. The air intakes were located behind the riders legs on the side keeping the airflow to the filters air box low pressure and undisturbed air flow.
As the engine was not wearing to any measurable degree very few particles were being released into the oil, the oil did a good job of keeping carbon of the pistons and skirts.
The only real avenue for particle ingress would have been the air filter which was always replaced sometimes before recommended interval and obviously did its job as no scoring was evident in the soft tri metal bearing overlay.
Basically it would appear this engine could have run with not much more than a screen for an oil filter with no ill effects.
If an engine is leaking unfiltered air like a sieve like some old carburetor engines did from places like carb to air cleaner connection because the gasket was long gone years ago or leaky pcv system then yes I believe a more efficient oil filter would be of some benefit but how much additional engine life will result from it?
Modern engines are very well sealed against unfiltered air ingress and judging by the reduced size of oil filters found on many engines these days the oil filters efficiency is less important than flow through the system.
Some engines like those from VW use a large filter not only for filtering but for additional capacity like on the earlier 1.8 turbo engines.
Using a quality air filter with tight connections and changed on schedule is IMO probably the most important part of keeping particles out of the engine.
The engines I have seen ruined by incorrect oil filters were Fiat diesels that knocked or seized right after an oil and filter change. I have no info on which filter was installed as I didn't install them, I just investigated the damage, the engines and filters were subsequently sent to Fiat through the dealer network.
I did note however the filter that caused the damage had an ADBV in both cases and the OE spec did not indicating this particular engine possibly used a different flow through the filter.
Trav,
The only engine I have ever seen that was torn down using M1 oils(many using dino) was a 1998 Ford Taurus 3.0 with 185K. The reason was my friends wife got caught in a flooded country road from a thunder storm. She couldn't see the ditch and drove into it and flooded the engine causing one rod to bend. My friend pulled the engine and measured all engine parts and all spec'd new. The engine was also was very clean. He replaced the rod and the rest is history. OIL FILTERS USED AT 10K OCI WAS MC FL400 FOR THE LIFE OF THE ENGINE(80-20ppm).I still maintain the oil you use is far more important than the filter you use.