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jbfla · 09-06-2016, 07:35 PM

Oil Analysis is complete,

And the results are surprising to me.

1% fuel in the oil.

This is with the crankcase vent hose running directly to the airbox.

No other changes to the bike were made.

The roads ridden, and the riding style were the same as the previous analysis.

Here are the comments from Blackstone:

JB: It's great to see fuel lower this time. There's still a little fuel in the oil, but 1.0% is not problematic as you can get this small of an amount simply from normal use. Potassium and sodium dropped this time, so coolant contamination is no longer a concern. The viscosity is still on the thin side for 20W/50, but with less fuel in the oil, it's closer to the should be range than past samples. Air and oil filtration still look good and wear metals are nice and low once again. They are holding pretty steady overall too and that's good. Better overall since fuel is lower.

I realize that one test doesn't prove anything unless it's repeated multiple times with the same results.

But it puts my mind at ease.

However, I've been doing some additional research, and it turns out that routing the crankcase gases directly to the airbox is not really a good thing.

An article in the Sept 2016 issue of Motorcycle Consumer News (p46) on "blow-by gases" going back into the engine intake states:

"the engine ...is inhaling a mixture of ambient air combined with water, burned and unburned fuel, combustion gases, ash and atomized engine oil that together readily form thick carbon deposits on the intake tract walls, and on the backsides of the intake valves....

......the consequences of this buildup: reduced airflow due to rough, narrowed passages caused by crusty surface....

...these oily gases add to the carbon buildup on the piston crowns and combustion chamber walls..."

And quite by accident I was watching the Motorweek TV show when this was mentioned:

http://www.motorweek.org/features/go...-oil-separator

It looks like routing the crankcase gases back to the engine intake (PCV valve) is a good thing for emissions, but not so good for the engine.

I think I will complete my second test with no crankcase gases going to the airbox.

Then install a new air/oil separator from CSC (already ordered), and try one last analysis.

.....That is if I can accumulate the miles here in North Carolina before the riding season ends for me. The RX3 will stay in NC when I return to FL.

jb

09-06-2016, 07:35 PM	#23
jbfla Join Date: Oct 2015 Location: FL, GA, NC Posts: 771	Oil Analysis is complete, And the results are surprising to me. 1% fuel in the oil. This is with the crankcase vent hose running directly to the airbox. No other changes to the bike were made. The roads ridden, and the riding style were the same as the previous analysis. Here are the comments from Blackstone: JB: It's great to see fuel lower this time. There's still a little fuel in the oil, but 1.0% is not problematic as you can get this small of an amount simply from normal use. Potassium and sodium dropped this time, so coolant contamination is no longer a concern. The viscosity is still on the thin side for 20W/50, but with less fuel in the oil, it's closer to the should be range than past samples. Air and oil filtration still look good and wear metals are nice and low once again. They are holding pretty steady overall too and that's good. Better overall since fuel is lower. I realize that one test doesn't prove anything unless it's repeated multiple times with the same results. But it puts my mind at ease. However, I've been doing some additional research, and it turns out that routing the crankcase gases directly to the airbox is not really a good thing. An article in the Sept 2016 issue of Motorcycle Consumer News (p46) on "blow-by gases" going back into the engine intake states: "the engine ...is inhaling a mixture of ambient air combined with water, burned and unburned fuel, combustion gases, ash and atomized engine oil that together readily form thick carbon deposits on the intake tract walls, and on the backsides of the intake valves.... ......the consequences of this buildup: reduced airflow due to rough, narrowed passages caused by crusty surface.... ...these oily gases add to the carbon buildup on the piston crowns and combustion chamber walls..." And quite by accident I was watching the Motorweek TV show when this was mentioned: http://www.motorweek.org/features/go...-oil-separator It looks like routing the crankcase gases back to the engine intake (PCV valve) is a good thing for emissions, but not so good for the engine. I think I will complete my second test with no crankcase gases going to the airbox. Then install a new air/oil separator from CSC (already ordered), and try one last analysis. .....That is if I can accumulate the miles here in North Carolina before the riding season ends for me. The RX3 will stay in NC when I return to FL. jb __________________ 2016 Honda CB500F......2017 Triumph Street Twin 2014 XT 250........
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