Oil Contaminant Separator (OCS) Orientation: The Official Word

[SpudRider]

The CSC Blog just announced the official word on the orientation of the oil contaminant separator (OCS). CSC says the clamp should be at the top, and the hose connected at the bottom, as shown in the link below. ;)

http://californiascooterco.com/blog/?p=21183

http://californiascooterco.com/blog/wp-content/uploads/2016/05/150501_6425-650.jpg

CSC is employing the exact same logic we concluded on this forum, but is aiming for a different result. ;) Placing the OCS in the CSC orientation maximizes the amount of fuel collected in the clear tube at the bottom of the OCS. Placing the OCS in the opposite orientation minimizes the amount of fuel collected in the OCS, and sends more atomized fuel to the air box, where it can be burned in the combustion process.

Less than a week ago I received a personal message regarding the OCS orientation from forum member Fritz, in Bavaria, Germany. I hope he doesn't mind if I post part of his message. ;)

I found something related to the fuel in the overflow line. According to the drawing in the documents showing the recirculation system, the orientation of the OCS is actually mounted correctly from the factory assuming the US setup is the same as the European.

Considering the fact that mounting it upside down will reduce the amount of fuel in the line I have an idea why it is still mounted as shown on the drawing.

A gas recycling device is probably compulsory so they added it. But burning this recirculated fuel can actually influence your emissions in a negative way. This is due to the fact that the fuel from crank case can not be considered by the ECU with this system setup (additional valve and carbon canister including a load model would change that) and therefore enriching the mixture in an uncontrolled manner. Which means only the feedback control of the lambda sonde can compensate when it is actually already to late and the lambda value is no longer 1 and the catalyst is not working at its most efficient operation point.

On the other hand I guess there is no regulation limiting the amount of fuel collected in the line since it is assumed that it will be disposed correctly.

Long story short the mount of the factory is correct according to the drawings provided for European type approval including emission testing.

So there you have it. ;) Mounting the OCS as shown in the photograph above is the offical orientation. As we have proven, it will result in more fuel being collected in the clear tube, and less fuel being added to the combustion process. This orientation is probably stipulated by exhaust emissions criteria, more than anything else. ;)

[SpudRider]

My OCS came from the factory with the opposite orientation, as did the initial bikes delivered to CSC, and many others on this forum. ;) I do know the official orientation will definitely collect more fuel in the clear tube below the OCS. ;)

At the 12:32 mark in the following video, you can see the OCS was not installed in the official orientation during the CSC Western States tour. ;)

https://www.youtube.com/watch?v=hV94X6iptZ4

[AdventureDad]

I dont have mine yet...but I'm wondering for those who take long rides, what happens when the tube gets totally filled and one keeps riding? I'm not saying ignore it, but if someone is doing a long ride out of state or whatever, and the tube gets filled and the rider misses it, what could a negative outcome be?

[Inroads]

I dont have mine yet...but I'm wondering for those who take long rides, what happens when the tube gets totally filled and one keeps riding? I'm not saying ignore it, but if someone is doing a long ride out of state or whatever, and the tube gets filled and the rider misses it, what could a negative outcome be?

Mine fills up fast on highway rides and so I have pulled my drain plug about
Half-way out to allow a slow drip out the bottom onto the ground.

[maxhdrm]

Interesting .... when I picked up my bike two weeks ago last Saturday at CSC my OCS valve was mounted in the "official" CSC position. At about 225 miles I did a oil change and drained about 3 inches of liquid from the line. About 60 miles ago I saw the posts about the "up side down" OCS and flipped the valve to the "non-official" position, last night saw the blog entry on the "official" OCS valve position so this afternoon I went to flip it back, notice no liquid in the tube but when I flipped the valve a nice puddle of fuel smelling liquid emptied out of the valve. Was not expecting that after only 60 or so miles! Oh and if you have the upgraded skid plate, it makes getting the OCS bracket off/on a bit more challenging! Glad it is all resolved!

[detours]

I dont have mine yet...but I'm wondering for those who take long rides, what happens when the tube gets totally filled and one keeps riding? I'm not saying ignore it, but if someone is doing a long ride out of state or whatever, and the tube gets filled and the rider misses it, what could a negative outcome be?

This has happened to me several times on rides longer than 3-4 hours. I've pulled the tube out from the OCS and liquid drips out of the OCS for a minute.

This means that fuel is starting to fill the OCS and block suction. When that happens, vapors will no longer be drawn from the crankcase and fuel will build up in your oil.

Obviously, you can drain it at every stop ... or pull the plug and let the fuel/oil/water drip to the ground all the time. But I really hate the idea of pouring out even more fuel than I already have to.

Unless I hear a convincing argument (as to why it's better to pour gas on the ground than to burn it), I'm going to stick with the opposite orientation. I've been running it like this for several thousand miles with no ill effects, no loss of power and good mpg (65 to 70 mpg).

And if it makes the engine run slightly richer ... well, I was going to pour that gas out anyway. I might as well give it a chance to burn inside the engine before sending it out the tailpipe.

[Ron B]

im going to stop by home depot on the way home and pick up one of these to replace the plug to make draining easier with out getting gas all over (lawn mower cut off)

[detours]

So there you have it. ;) Mounting the OCS as shown in the photograph above is the offical orientation. As we have proven, it will result in more fuel being collected in the clear tube, and less fuel being added to the combustion process. This orientation is probably stipulated by exhaust emissions criteria, more than anything else. ;)

I have much to learn about emissions and fuel injection systems. But doesn't the O2 sensor detect O2 in the exhaust and optimize fuel injection to compensate?

In other words, if extra fuel vapor is added from the OCS, wouldn't the fuel injection system reduce fuel for an optimal mix?

[kohburn]

CSC is employing the exact same logic we concluded on this forum, but is aiming for a different result. ;) Placing the OCS in the CSC orientation maximizes the amount of fuel collected in the clear tube at the bottom of the OCS. Placing the OCS in the opposite orientation minimizes the amount of fuel collected in the OCS, and sends more atomized fuel to the air box, where it can be burned in the combustion process.

and emissions, ok yeah that makes sense that it would be done that way for emissions. on cars i've only ever used a catch can in the crank case vent line to avoid oil fowling of the intake sensors and spark plugs. never a concern about unburnt fuel vapor.

[SpudRider]

I dont have mine yet...but I'm wondering for those who take long rides, what happens when the tube gets totally filled and one keeps riding? I'm not saying ignore it, but if someone is doing a long ride out of state or whatever, and the tube gets filled and the rider misses it, what could a negative outcome be?

If the water/fuel mixture rises to the top of the OCS, the air box will be unable to draw the contaminated fumes from the crankcase. Therefore, the fuel and water will remain in the crankcase, contaminating and thinning the engine oil. ;)

[SpudRider]

This has happened to me several times on rides longer than 3-4 hours. I've pulled the tube out from the OCS and liquid drips out of the OCS for a minute.

This means that fuel is starting to fill the OCS and block suction. When that happens, vapors will no longer be drawn from the crankcase and fuel will build up in your oil...

That is exactly correct. :)

...Obviously, you can drain it at every stop ... or pull the plug and let the fuel/oil/water drip to the ground all the time. But I really hate the idea of pouring out even more fuel than I already have to...

I would not pull the plug. The suction from the crankcase can draw dust, water vapor, and other contaminants into the crankcase, and/or plug the mesh screen within the OCS. ;)

...Unless I hear a convincing argument (as to why it's better to pour gas on the ground than to burn it), I'm going to stick with the opposite orientation. I've been running it like this for several thousand miles with no ill effects, no loss of power and good mpg (65 to 70 mpg).

And if it makes the engine run slightly richer ... well, I was going to pour that gas out anyway. I might as well give it a chance to burn inside the engine before sending it out the tailpipe.

I'm with you. ;) My RX3 was delivered with the OCS in the "unofficial" position. Since then I have ridden over 14,000 miles with my OCS in the "unofficial" position, and I have not noticed any ill effects whatsover. ;) In addition, the OCS for my Honda XR650L is designed to burn the fuel vapors.

http://i729.photobucket.com/albums/ww300/XRL_royal/motor/oil_sep2.jpg

I can't see how it is preferable to spill the fuel, rather than burn it. :shrug:

[SpudRider]

I have much to learn about emissions and fuel injection systems. But doesn't the O2 sensor detect O2 in the exhaust and optimize fuel injection to compensate?

In other words, if extra fuel vapor is added from the OCS, wouldn't the fuel injection system reduce fuel for an optimal mix?

Yes, you are correct if the O2 sensor is operating in a closed loop. :) I might be mistaken, but I believe our EFI systems don't operate in closed loop much of the time. However, I also have much to learn regarding EFI systems. ;) Nevertheless, the O2 sensor should help to optimize the fuel/air mixture, as shown in the video below.

However, after watching the video, you will note that automotive systems employ two O2 sensors. One is located in front of the catalytic converter, and one is located behind the catalytic converter. While the first O2 sensor acts to optimize the fuel/air ratio, the second O2 sensor monitors the efficiency of the catalytic converter. Since our bikes lack the O2 sensor behind the catalytic converter, it is possible that exhaust emissions can be adversely affected by the extra fuel vapor introduced from the air box. ;)

Nevertheless, it appears the RX3 bike submitted by CSC for EPA and CARB approval probably also had the OCS installed in the "unofficial" position, as it was with my own RX3. ;) Therefore, I really don't see many adverse effects for burning the extra fuel, instead of spilling it on the ground. ;)

https://www.youtube.com/watch?v=Fl3aD1qJrEg

[CSaddict]

I just flipped mine which is more difficult due to the aluminium skid. I'll flip it back.

[pyoungbl]

Every motorcycle EFI system I'm familiar with (Ducati, Triumph, Moto Guzzi) runs in closed loop up to about 3500 rpm and then switches to open loop for higher rpms. Ours might have a higher crossover point but I'm pretty sure the closed loop is only significant for us at idle or just above idle. The EPA cycle could possibly dictate testing at some highway speed as opposed to a specific rpm range so that in itself would modify where the ECU goes from closed to open loop. On the other bikes it is common to have drivability issues at low throttle settings unless the ECU is re-mapped or the owner installs a gadget like a Power Commander to modify the fuel delivery. We do not seem to have that problem and I see no need to mess with the fuel map.

The amount of fuel being dumped by the OCS is really pretty small. I'd guess less than a cc in the batch that I dumped. There is much more water. Personally, I'm happy to see any water vapor being pulled from the crankcase. If it goes to the airbox or the ground...either is a good thing just as long as it is not in the oil. One could always install a larger catch bottle if the volume is a concern.

[Juanro]

And what if one connected the crankcase directly to the air box?
Wouldn't it be then that all contaminants would be burned? And then forget about draining or collecting...

[2LZ]

I'm not sure about motorcycle EFI's but back in the day when I was a wrench, car injections systems were only in open loop in "choke mode" and the ECM would function is set, mapped parameters. Once they heated up to operating temp, they switched to closed loop and stayed there allowing the O2 sensor and map/baro or MAF sensors to do their jobs and adjust air/fuel ration constantly through block learn and integrator in your ECM. If this is the case here, the O2 sensor would sniff the extra fuel being recycled and shorten the injector pulse width slightly to keep the air-fuel ratio as close to 14.7/1 as possible.
If this injection system works like that, I have no idea..........

[SpudRider]

Every motorcycle EFI system I'm familiar with (Ducati, Triumph, Moto Guzzi) runs in closed loop up to about 3500 rpm and then switches to open loop for higher rpms. Ours might have a higher crossover point but I'm pretty sure the closed loop is only significant for us at idle or just above idle. The EPA cycle could possibly dictate testing at some highway speed as opposed to a specific rpm range so that in itself would modify where the ECU goes from closed to open loop. On the other bikes it is common to have drivability issues at low throttle settings unless the ECU is re-mapped or the owner installs a gadget like a Power Commander to modify the fuel delivery. We do not seem to have that problem and I see no need to mess with the fuel map.

The amount of fuel being dumped by the OCS is really pretty small. I'd guess less than a cc in the batch that I dumped. There is much more water. Personally, I'm happy to see any water vapor being pulled from the crankcase. If it goes to the airbox or the ground...either is a good thing just as long as it is not in the oil. One could always install a larger catch bottle if the volume is a concern.

Thanks for your input, Peter. :) If you can provide links to any good articles regarding EFI systems, please do post them. We are always eager to learn more. :)

I agree with you completely; the OCS does a great job removing fuel and water contaminants from engine oil in the crankcase. :tup: Also, I'm sure most of the liquid content is water. :)

[detours]

And what if one connected the crankcase directly to the air box?
Wouldn't it be then that all contaminants would be burned? And then forget about draining or collecting...

I've wondered about that myself. My only concern would be that condensation inside the line would run back into the crankcase ... or get caught in a U-bend and block suction.

[SpudRider]

And what if one connected the crankcase directly to the air box?
Wouldn't it be then that all contaminants would be burned? And then forget about draining or collecting...

Many motorcycles do exactly as you stated. :) However, having an oil contaminant system is a superior design. The OCS traps contaminants as quickly as possible, and eliminates them from the crankcase. The single, long vertical hose employed by the other systems allows many contaminants to flow back into the crankcase before they ever reach the air box. ;)

[SpudRider]

I'm not sure about motorcycle EFI's but back in the day when I was a wrench, car injections systems were only in open loop in "choke mode" and the ECM would function is set, mapped parameters. Once they heated up to operating temp, they switched to closed loop and stayed there allowing the O2 sensor and map/baro or MAF sensors to do their jobs and adjust air/fuel ration constantly through block learn and integrator in your ECM. If this is the case here, the O2 sensor would sniff the extra fuel being recycled and shorten the injector pulse width slightly to keep the air-fuel ratio as close to 14.7/1 as possible.
If this injection system works like that, I have no idea..........

I think you know more than I about EFI systems, 2LZ. ;) However, I am basing some of my speculations on the information I obtained from talking to the people at Dobeck Performance, when I was considering working with them to produce a EJK module for the RX3.

http://www.electronicjetkit.com/default.asp
http://www.dobeckperformance.com/

[SpudRider]

I've wondered about that myself. My only concern would be that condensation inside the line would run back into the crankcase ... or get caught in a U-bend and block suction.

Once again, you are correct, amigo. ;) A lot of the water, and some of the fuel would drop back into the crankcase oil before it reached the air box. The OCS for the Zongshen RX3 is a very nice design. :tup:

[Juanro]

I guess if it comes out of the crankcase as vapor it could, in part, condensate over the pipe walls.. the OCS anyway is doing that on purpose.
Any fluid going back to the oil will evaporate again, in the next hot cycle.
Having a straight pipe is mandatory, anyway, any U bend will act as a reservoir and eventually fill up.
I'm not too fond of having to drain the OCS pipe, and in long trips it have filled up and made somewhat of a mess spilling oily fluid all over engine side. Nothing to worry about, my bike spends most of the time filthy anyway, haha

[keithmaine]

I've wondered about that myself. My only concern would be that condensation inside the line would run back into the crankcase ... or get caught in a U-bend and block suction.

you would not believe the crap in the air cleaner of my Ural that does just that, milky condensation mixed with an oily mess.

[dave92029]

Very interesting discussion, BUT for us non mechanics, would someone PLEASE post a picture of the best way to mount the OCS. Apparently there are merits to mounting the OCS both ways.

I "presume" that the preferred/ best method is the one that keeps "stuff" out of the crankcase and allows the engine to run smoothly at all rpm's.

Thanks for all your input. :thanks:

[detours]

Very interesting discussion, BUT for us non mechanics, would someone PLEASE post a picture of the best way to mount the OCS. Apparently there are merits to mounting the OCS both ways.

I "presume" that the preferred/ best method is the one that keeps "stuff" out of the crankcase and allows the engine to run smoothly at all rpm's.

Thanks for all your input. :thanks:

I'm not sure one way is more effective than the other at pulling vapor from the crankcase. Spud has run his 14,000 miles in the 'unofficial' orientation without ill effects. Myself and others have thousands of miles in the unofficial orientation.

To me, it's a question of whether you want more or less fluid in the catchtube:


Official (cap toward top): More fuel vapor condenses in the catchtube. Less fuel vapor pulled into the air intake. Higher risk of filling up the OCS (and blocking suction) on long trips. Potentially better tailpipe emissions, but more fuel to pour on the ground.
Unofficial (cap toward bottom): Less fuel vapor condenses in the catchtube. More fuel vapor pulled into the air intake. Lower risk of filling up the OCS (and blocking suction) on long trips. Potentially worse tailpipe emissions, but less fuel to pour on the ground.


For my part, unless CSC says the OCS orientation will affect my warranty ... or until I learn compelling reasons why burning fuel vapor from the OCS is worse on the environment than pouring fuel condensate on the ground ... I intend to mount my OCS 'upside-down', so as to burn as much of the fuel vapor from the crankcase as possible and to collect as little fuel in the catchtube as possible.

[willy dog]

i am leaning on the side of detours but then again not sure i want to burn the crap at the bottom of the tube might be draining it the way to go well getting very good at flipping it kind of like my opinion :hmm::doh:

[detours]

i am leaning on the side of detours but then again not sure i want to burn the crap at the bottom of the tube might be draining it the way to go well getting very good at flipping it kind of like my opinion :hmm::doh:

Oil and contaminants are actually at less risk of entering the airbox in the 'upside down' orientation.

Remember, the OCS filter is shaped like a cup.

http://www.chinariders.net/attachment.php?attachmentid=3487&stc=1&d=1443404374

In the 'upside down' orientation, vapors must pass through 2 filter walls (the side and the floor of the filter) before reaching the air intake. Heavy contaminants like oil and particulates will be filtered out by one or the other filter wall, dissolved in condensate fuel and dropped into the catchtube.

http://www.chinariders.net/attachment.php?attachmentid=3659&stc=1&d=1444755580

In the opposite 'official' orientation, vapor will only pass through one filter wall and up the open part of the cup. This is another reason why I like the 'upside down' orientation.

[SpudRider]

...For my part, unless CSC says the OCS orientation will affect my warranty ... or until I learn compelling reasons why burning fuel vapor from the OCS is worse on the environment than pouring fuel condensate on the ground ... I intend to mount my OCS 'upside-down', so as to burn as much of the fuel vapor from the crankcase as possible and to collect as little fuel in the catchtube as possible.

I agree. :) I was planning to flip my OCS as an experiment, but I noticed the hose from the crankcase cover to the OCS was kinked at an acute angle. :ohno: Given the location of the mounting plate, the OCS is positioned at a much more natural orientation in the "unofficial" position. After riding over 14,000 miles without any problems, I don't see a good reason to change the position now. ;) I much prefer to burn the captured fuel, rather than dump it. However, I don't think it will harm anything to mount the OCS either way. ;)

[kumatae]

I just flipped mine around even though I've been riding trouble free for 8000 miles. I noticed that tube was filled with gas. I never had bother to drain it this whole time.

I agree with spudrider that the hose does seem kinked in acute angle but I went ahead and did the flip. Maybe later when I have more time, I'll shorten the tube to make it more natural. The process probably took all of 10 minutes at the max.

[rtking]

I flipped mine around to the "correct" orientation, but I don't like the kinked hose. I slept on it overnight and I'm pretty certain I'm going to change it back to the way it came (i.e. the "incorrect" orientation) as it never gave me a lick of trouble.

[rjmorel]

I flipped mine around also and saw the kinky hose. I can push the kink of hose together about 1/8" just by pushing down on the top of the kink so I know it's not kinked flat shut. I will ride it a few weeks and see how it goes and flip it back if something undesirable happens. rj

[detours]

Joe Berk posted some interesting information about the OCS in this CSC blog post ...

http://californiascooterco.com/blog/?p=21317

He recently changed his OCS to the official orientation and has gotten no liquid in the tube like he used to.

I'm interested in his results because they were the opposite of mine. I wonder if his results will be consistent over time and if he is certain his catch tube is well sealed at the bottom. many people think they aren't collecting fluid because it leaks out around the plug.

I tested three scenarios last year with the OCS (http://www.chinariders.net/showpost.php?p=201909&postcount=151), and the unofficial position collected the least amount of fluid.

My test conditions:

Clean and sand the bottom cap to ensure a good seal.
Take the same route to work (about 40 miles round trip).
Maintain approximately the same speed during each commute. mixed city and highway from 35 mph to 60 mph.
Travel at approximately the same time and temperatures.


My results:

Official position (cup-shaped filter open at the top) (http://www.chinariders.net/attachment.php?attachmentid=3483&stc=1&d=1443403488) -> about 3/4 filled.
Official position with filter wall drilled through -> almost full.
Unofficial position (cup-shaped filter open at the bottom (http://www.chinariders.net/attachment.php?attachmentid=3659&stc=1&d=1444755580)) -> about 1/2 full.


My conclusions:

With two filter surfaces (side and top) in the unofficial position, I collected the least fluid. With one filter wall (side only, open at top), I collected some fluid. With no filter wall (drilled through), I collected the most fluid.

My data indicates an inverse relationship between the amount of filter material in the OCS and the amount of fluid collected. Spud theorized that (http://www.chinariders.net/showthread.php?t=15332&highlight=condensation+pressure&page=4) the reduced filter material from drilling a hole in the media increases the speed of the gases from the crankcase, lowering vapor pressure and increasing condensation ... which would explain why the tube fills faster with less filter media in the way.

Increasing the amount of filter media, by passing crankcase gases through two filter walls in the unofficial orientation, slows down the vapor. This raises vapor pressure, reduces condensation and sends more fuel vapor to the air intake to be burned during combustion ... leaving less liquid in the catch tube.

[SpudRider]

I agree with you completely, amigo. ;)

I suspect the plug is leaking on Joe's bike. If he seals the plug and keeps checking for an extended period of time, I'm sure he will see the same results as you. ;) You followed a scientific approach, and tried to keep all variables the same, except for the orientation of the OCS. :tup: No one else has followed your disciplined, scientific method of examining this issue. ;)

Incidentally, RJMorel has also verified your results. ;)

http://www.chinariders.net/showpost.php?p=215475&postcount=57

[keithmaine]

detours

I would just like to :thanks: for all the testing and reporting back with great information. It is guys like you, Spud and several others that make this forum such an asset.

[AdventureDad]

There is an interesting post on ADV rider on the RX3 thread about this, and something for everyone to watch out for... seems his hoses to the seperator gave up the ghost due to becoming hard and brittle. He also modified it with initial major improvement.

http://advrider.com/index.php?threads/csc-250cc-rx-3-cyclone.1007040/page-144#post-29372699

[detours]

There is an interesting post on ADV rider on the RX3 thread about this, and something for everyone to watch out for... seems his hoses to the seperator gave up the ghost due to becoming hard and brittle. He also modified it with initial major improvement.

http://advrider.com/index.php?threads/csc-250cc-rx-3-cyclone.1007040/page-144#post-29372699

Very interesting. I'll have to check my OCS hoses for damage too.

I've considered a straighter shot to the airbox. On the one hand, fuel and water condensation could drip back into the crankcase. On the other hand, on long runs where the crankcase stays hot, fuel and water vapor will be continuously drawn into the airbox. Pros and cons either way.

[detours]

I agree with you completely, amigo. ;)

I suspect the plug is leaking on Joe's bike. If he seals the plug and keeps checking for an extended period of time, I'm sure he will see the same results as you. ;) You followed a scientific approach, and tried to keep all variables the same, except for the orientation of the OCS. :tup: No one else has followed your disciplined, scientific method of examining this issue. ;)

Incidentally, RJMorel has also verified your results. ;)

http://www.chinariders.net/showpost.php?p=215475&postcount=57

Thanks, but my test really only determines which method collects more fluid in the tube ... Not how efficiently vapor is scavenged or how much vapor makes it to the airbox without condensing. It's possible that the unofficial 'upside down' position blocks airflow and leaves more fuel in the oil. A systematic oil test with the OCS in each position would tell us for sure.

But I'm not sure it matters. Of course I don't want fuel in my oil, but as far as the environment goes, less fuel in the tube means less poured on the ground. The rest is either burned in combustion or recycled in my regular oil changes before it can damage my engine.

[SpudRider]

I have never changed the orientation of my OCS since I received it from CSC. As with many other RX3 bikes, my OCS was installed in the "unoffical" orientation from the factory. I'm pleased to report my used engine oil is always in excellent condition. ;)

[rjmorel]

My hose has cracks on the outside of it that showed up when I flipped the osc last week also. :grr:
I was watching a MX race on TV this weekend and the announcer was pointing out the steam coming out of the bikes breather hose , looked like a cappuccino machine so much was coming out from the hot motors. They showed several bikes doing this. I think they would of filled up the tube in 1 race. :hmm:

[SpudRider]

detours

I would just like to :thanks: for all the testing and reporting back with great information. It is guys like you, Spud and several others that make this forum such an asset.

Thank you, Keith.

We appreciate having helpful, polite members such as yourself, who contribute knowledge to this forum. :) Unfortunately, we occasionally encounter people who eagerly gather information from others without acknowledging the source, yet they contribute little or nothing themselves. Instead, they insist on starting arguments, and insulting others. Needless to say, we are fortunate when these people leave, either voluntarily, or involuntarily. ;)

[Lee R]

I just flipped my OCS back to the "official" position which was the way it came from the factory, the hose was still in good shape after 1000 miles but I'll continue checking for cracks as it may be fuel vapor/fuel sensitive.

It'll be interesting to see if the tube still fills after the bikes had a bit more mileage. I have another oil change at 2000 miles and I'm getting the oil analyzed again to see if it's still got an abnormal amount of fuel in it.

[detours]

I just flipped my OCS back to the "official" position which was the way it came from the factory, the hose was still in good shape after 1000 miles but I'll continue checking for cracks as it may be fuel vapor/fuel sensitive.

It'll be interesting to see if the tube still fills after the bikes had a bit more mileage. I have another oil change at 2000 miles and I'm getting the oil analyzed again to see if it's still got an abnormal amount of fuel in it.

Hey Lee, I found your oil analysis in the other thread, and it shows 4.5% fuel content. Was that your bike's first oil change? And was your OCS in the official position for that oil change interval?

[Lee R]

Hey Lee, I found your oil analysis in the other thread, and it shows 4.5% fuel content. Was that your bike's first oil change? And was your OCS in the official position for that oil change interval?

That was the second oil change, oil had 500 miles on the sample between mileage 500-1000. OCS was in "official" position at that time, I flipped it @ 1000 miles. Both the initial and second oil change smelled strongly of fuel.

I spoke to Gerry about it while I was in California in person and he said it's normal and should be OK after break in. I'll be sending another sample to be sure at the 2000 mile mark this week.

[pyoungbl]

Just a thought...as the piston rises and falls the crankcase goes through a pressure/partial vacuum cycle twice for every time the plug fires. Now, that's only 249cc moving around but it's still pumping/sucking really quickly. I'm wondering if the OCS has a secondary purpose, to dampen these waves as any blowby heads to the airbox. This should not be a steady push of gas unless the rings are shot, more like the vibration you get from the head of a drum. If I'm correct the water/fuel/oil particles get stripped on each push/suck, falling into the clear tube. I still do not understand why we get so much water in the tube but then, I did not do good in college chemistry either.

Peter Y.

[RX3James]

I've been reading a lot about the orientation of the OCS lately. So today I decided to take a look at mine. As you can see it's not in the correct position. Only one time did I ever notice any fluid build up in the tube and it was when I was doing the break in oil change. It is pretty obvious with the discoloration of the tube that there has been fluid going through the tube for some time. I suspect its not building up in the tube because the plug isn't exactly water tight. So here's the real question..... I have not noticed any real issue with the bike. It runs and rides just fine. I think now that I've finally broken 2000 miles on it that I've worked out most of the bugs. So should I even worry about he orientation? Should I even spend the 5 minutes to flip it? What is it going to hurt if I just let it roll like it is? If there is no real benefit then I think I'm going to just leave it be. What do you guys and gals think?

Ride safe friends!

[SpudRider]

I've been reading a lot about the orientation of the OCS lately. So today I decided to take a look at mine. As you can see it's not in the correct position. Only one time did I ever notice any fluid build up in the tube and it was when I was doing the break in oil change. It is pretty obvious with the discoloration of the tube that there has been fluid going through the tube for some time. I suspect its not building up in the tube because the plug isn't exactly water tight....

You are correct. My RX3 was delivered with the OCS in the same position as yours. I did not collect any fluid in the tube last year, because the seal was not tight. Over the winter the tube shrunk a bit, which tightened the seal with the plug. Therefore, I am now starting to collect fluid in the tube. ;)

...So here's the real question..... I have not noticed any real issue with the bike. It runs and rides just fine. I think now that I've finally broken 2000 miles on it that I've worked out most of the bugs. So should I even worry about he orientation? Should I even spend the 5 minutes to flip it? What is it going to hurt if I just let it roll like it is? If there is no real benefit then I think I'm going to just leave it be. What do you guys and gals think?

Ride safe friends!

I have ridden my bike over 14,000 miles with the OCS in the 'unofficial' position. My bike also runs well, without any problems whatsoever. Indeed, at least some, if not all the bikes on the Western States ride also had the OCS oriented in the 'unofficial' position. Those bikes didn't have any problems, either. ;)

Obviously, you don't have anything to worry about by keeping the OCS in the current, 'unofficial' orientation. ;) Indeed, I would't waste five minutes to flip it, unless you want to experiment. If you do decide to flip the OCS, you will probably bend the tubing more acutely, which will probably cause the tubing to crack and fail more quickly. I can't see any benefit resulting from flipping the OCS to the 'official' position. :shrug:

[SpudRider]

...So should I even worry about he orientation? Should I even spend the 5 minutes to flip it? What is it going to hurt if I just let it roll like it is? If there is no real benefit then I think I'm going to just leave it be. What do you guys and gals think?

Ride safe friends!

If you do decide to flip the OCS to the 'official' position for an experiment, you will collect more fluid in the OCS than now. Detours has proven this by valid experimentation. His results have also been confirmed by others who leave the OCS in the 'official' position for more than several days. ;)

I have ridden my RX3 over 14,000 miles with my OCS in the 'unoffical' position. Every time I have changed my engine oil, the used oil was in excellent condition. Therefore, I'm sure I am collecting all the fuel and water contaminants from the engine oil. If you flip the OCS to the 'official' position, you will get more contaminants collected in the tube, which means less fuel vapor is being routed to the air box, and burned in the engine. Detours explains this matter in his usual intelligent, concise manner, in post #32 of this thread. ;)

[3banger]

So here is the solution I will be testing out. Every other motorcycle I've ever owned or that I'm aware of vent from the crankcase directly to the air box with out all this OCS stuff. With a simple mod this can be accomplished on the RX3. I'm sure this will have warranty voiding implications if something I don't for see cause an engine related failure; Joe I realize that up front since I'm sharing this here.

As of right now this is an experiment and I don't encourage anyone else to following suit. But the engineer in me can't leave well enough alone; I'll keep everyone posted.

[detours]

So here is the solution I will be testing out. Every other motorcycle I've ever owned or that I'm aware of vent from the crankcase directly to the air box with out all this OCS stuff. With a simple mod this can be accomplished on the RX3. I'm sure this will have warranty voiding implications if something I don't for see cause an engine related failure; Joe I realize that up front since I'm sharing this here.

As of right now this is an experiment and I don't encourage anyone else to following suit. But the engineer in me can't leave well enough alone; I'll keep everyone posted.

What a great experiment! I see several potential advantages:

Shorter line to the airbox could mean less condensation
With no trap to fill, all vapor is burned in the intake. (None poured on the ground)


And some potential disadvantages:

Heavy contaminants are not caught in the trap and stay in the crankcase.
The straight shot will likely mean a faster stream of vapor. This creates a pressure drop, causing more liquid to condense than in a slower stream.
Without a trap, condensation drops directly into the crankcase.


It's like a race ... Will the straight shot draw vapor into the airbox faster than it can condense and fall back into the crankcase?

As you test this setup, check the catch tube under the airbox after each run. I'll be very curious if liquid makes it to the airbox and is trapped there.

[Haggis]

So here is the solution I will be testing out. Every other motorcycle I've ever owned or that I'm aware of vent from the crankcase directly to the air box with out all this OCS stuff. With a simple mod this can be accomplished on the RX3. I'm sure this will have warranty voiding implications if something I don't for see cause an engine related failure; Joe I realize that up front since I'm sharing this here.

As of right now this is an experiment and I don't encourage anyone else to following suit. But the engineer in me can't leave well enough alone; I'll keep everyone posted.

That's exactly how GasGas run it, straight from crankcase to airbox.

http://i1179.photobucket.com/albums/x395/krodkiss/Mobile%20Uploads/99991179_007_zpsytorn9fe.jpg (http://s1179.photobucket.com/user/krodkiss/media/Mobile%20Uploads/99991179_007_zpsytorn9fe.jpg.html)

[katflap]

In some performance car circles a separator is considered an enhancement, adding "catch cans" to their crankcase emissions system.

Apparently, oil vapour entering the combustion chamber can be detrimental to performance and fuel economy.

Zongshen didn't have to add this separator to pass emission standards, a straight forward tube will do that.

Blow-by gasses also contain acids that I guess wouldn't be good for the EFI sensors.

Perhaps these are the reasons its been added.

[SpudRider]

In some performance car circles a separator is considered an enhancement, adding "catch cans" to their crankcase emissions system.

Apparently, oil vapour entering the combustion chamber can be detrimental to performance and fuel economy.

Zongshen didn't have to add this separator to pass emission standards, a straight forward tube will do that.

Blow-by gasses also contain acids that I guess wouldn't be good for the EFI sensors.

Perhaps these are the reasons its been added.

As always, you make excellent points, Kat. :) The Gas Gas bike in question has a carburetor.

However, I received my bike with an OCS in the "unofficial" position, and it ha been running very well for almost 15,000 miles, and averaging 68 mpg. Therefore, I don't see how keeping the OCS in the "unofficial" position can be detrimental to performance and economy. :shrug:

I wonder how other motorcycles with EFI vent the crankcase gasses?

[dpl096]

I thought Joe's blog today was a fair and honest explanation of the mechanics of the issue and, for me at least, eases most of my concern of the 4 to 5% levels recently seen in the oil analysis. I'm still not certain it's a genuine constant across the board as everyone rides differently. I'm going to leave mine, when it arrives, in the correct orientation and will probably send a sample off to Blackstone at the 1000 mile mark for peace of mind - otherwise I'm gonna go with Joe's assurance and ride in peace. Might bump up to a heavier oil down the line but for the first 1000 I'll stick with the Mobil. What say the rest of you regarding Joe's blog ? ? ?

[pyoungbl]

I wonder how other motorcycles with EFI vent the crankcase gasses?
Ducati, Triumph, Moto Guzzi, BMW...all vent to the airbox....at least all of mine did. EPA won't pass them if they vent to the atmosphere. Note that all of them are much larger displacement engines so the pumping action is more pronounced. Good venting is critical because otherwise you risk blowing oil seals in the engine.

[katflap]

As always, you make excellent points, Kat. :) The Gas Gas bike in question has a carburetor.

However, I received my bike with an OCS in the "unofficial" position, and it ha been running very well for almost 15,000 miles, and averaging 68 mpg. Therefore, I don't see how keeping the OCS in the "unofficial" position can be detrimental to performance and economy. :shrug:

I wonder how other motorcycles with EFI vent the crankcase gasses?

Sorry, how it meant to read was that having the OCS is a good thing as it will help to stop the oil vapour reaching the intake.

where a straight tube without the OCS will not and possibly have a detrimental effect on performance and economy.

As to the orientation of the OCS, i have no idea :shrug:

[SpudRider]

Ducati, Triumph, Moto Guzzi, BMW...all vent to the airbox....at least all of mine did. EPA won't pass them if they vent to the atmosphere. Note that all of them are much larger displacement engines so the pumping action is more pronounced. Good venting is critical because otherwise you risk blowing oil seals in the engine.

Thank you for posting the good information, Peter. :)

I assumed all bikes with EFI vent to the air box. All of my street legal bikes vent to the air box. Many dirt bikes vent to the atmosphere, but they don't need to pass EPA or DOT requirements. I am wondering if your previous EFI motorcycles employed an OCS, or if they vented directly to the air box without an OCS?

[SpudRider]

Sorry, how it meant to read was that having the OCS is a good thing as it will help to stop the oil vapour reaching the intake.

where a straight tube without the OCS will not and possibly have a detrimental effect on performance and economy.

As to the orientation of the OCS, i have no idea :shrug:

I understand, Kat. ;) I'm inclined to agree with you about the inclusion of the OCS. However, I wonder if other motorcycles with EFI also employ an OCS?

[katflap]

I guess there must be some out there

This image comes from a motor cycle technology book but the outline looks like a carb :)

5947

[keithmaine]

The new fuel injected Urals go direct into the air box just like the carb version
as you can see below. The carb version does get a lot of oil and condensation in the air box

http://imz-ural.com/img/motorcycles/2015/sportsman/studio-hero.jpg

[2LZ]

Almost all of the early EFI's fired a load of fuel every stroke, whether the intake valve was open or not. That "blank" spray of fuel would sit on the back of the intake valve and vaporize/atomize while it waited. This process also increased the intake valve build-up due to the olefins and diolefins in the fuel. Ford (in American cars) brought out the first "SEFI" system that only fired when the intake valve opened.
I've heard that many EFI's today still work firing a charge every stroke. I wonder if the EFI on the RX3 fires in this fashion, with the injector firing every stroke? This may possibly increase the fuel in the oil (or drain tube). Does anyone know the actual injector firing sequence?
Just a thought......

[pyoungbl]

I am wondering if your previous EFI motorcycles employed an OCS, or if they vented directly to the air box without an OCS?
The '07 Norge had a drain just like what we have but I recall that it came directly from the airbox. Guzzi engines would pump oil up to the airbox if the crankcase was over filled. Most of the newer Guzzi engines want to be filled no more than 1/2 way between low and full, any more than 1/2 way and they will pump oil to the airbox until the engine reaches its 'happy state'. The Stelvio and V7 do not have a separator that I'm aware of and I do not recall ever seeing one on any Ducati I owned (4 of them), the G650GS, or the Triumph Tiger. All vented direct from crankcase to airbox. None of those bikes ever had more than 0.5 % fuel in the oil. The Ducks did tend to build up water in the oil (air and water cooled bikes but over cooled) and this mayo would disappear after a good hot run. The separator we have does not seem to be a problem, just drain it as needed, so I do not intend to 'fix' it. I did not see anything after my last trip. Although I rode through 3 different rainstorms the bike was always showing at least 3 and sometimes 4 bars, particularly on some of the long mountain pulls. I was surprised that the fan never came on.

[katflap]

Almost all of the early EFI's fired a load of fuel every stroke, whether the intake valve was open or not. That "blank" spray of fuel would sit on the back of the intake valve and vaporize/atomize while it waited. This process also increased the intake valve build-up due to the olefins and diolefins in the fuel. Ford (in American cars) brought out the first "SEFI" system that only fired when the intake valve opened.
I've heard that many EFI's today still work firing a charge every stroke. I wonder if the EFI on the RX3 fires in this fashion, with the injector firing every stroke? This may possibly increase the fuel in the oil (or drain tube). Does anyone know the actual injector firing sequence?
Just a thought......

Yes our EFI can detect the inlet stroke :)

(taken from PCHUD sensor description)

MAPCID ENABLED- ( MANIFOLD ABSOLUTE PRESSURE (sensor), CYLINDER INLET DETECTION) - cylinder detection negates the need for a camshaft position sensor
When engine cylinder is working in intake stroke, the intake valve suddenly
opens, and the manifold pressure near the intake valve drops sharply
(by about 1kPa). The sharp drop of pressure is detected by the MAP sensor,
the ECU processes this signal by means of
the software, to determine stroke. Enabling spark ignition and fuel injection to be on the correct stroke

[2LZ]

Yes our EFI can detect the inlet stroke :)

(taken from PCHUD sensor description)

MAPCID ENABLED- ( MANIFOLD ABSOLUTE PRESSURE (sensor), CYLINDER INLET DETECTION) - cylinder detection negates the need for a camshaft position sensor
When engine cylinder is working in intake stroke, the intake valve suddenly
opens, and the manifold pressure near the intake valve drops sharply
(by about 1kPa). The sharp drop of pressure is detected by the MAP sensor,
the ECU processes this signal by means of
the software, to determine stroke. Enabling spark ignition and fuel injection to be on the correct stroke
Excellent! Great work, katflap and good to know! :-)

[BlackBike]

OK there will be a quiz for rx3 owners:p

[katflap]

Oil and contaminants are actually at less risk of entering the airbox in the 'upside down' orientation.

Remember, the OCS filter is shaped like a cup.

http://www.chinariders.net/attachment.php?attachmentid=3487&stc=1&d=1443404374

In the 'upside down' orientation, vapors must pass through 2 filter walls (the side and the floor of the filter) before reaching the air intake. Heavy contaminants like oil and particulates will be filtered out by one or the other filter wall, dissolved in condensate fuel and dropped into the catchtube.

http://www.chinariders.net/attachment.php?attachmentid=3659&stc=1&d=1444755580

In the opposite 'official' orientation, vapor will only pass through one filter wall and up the open part of the cup. This is another reason why I like the 'upside down' orientation.

For some reason my OCS differs from yours :hmm:

My original OCS chemically melted, this one is a replacement from China, so perhaps this is why.

( your bikes in the USA are updated and don't suffer from a melting OCS)

So for me, changing the orientation means that one way passes through the filter, the other way does not.

5958

5959

[Inroads]

In anticipation of an increase in contaminants in my drain tube by
Flipping it to the official position I have taken a Lawnmower fuel shut-off
Valve sleeved to the size of the drain tube and removed the plug.
Now I can just open the valve at my stops and drain it.

[Ron B]

In anticipation of an increase in contaminants in my drain tube by
Flipping it to the official position I have taken a Lawnmower fuel shut-off
Valve sleeved to the size of the drain tube and removed the plug.
Now I can just open the valve at my stops and drain it.
that was one of the first things I did.

[Ron B]

CSC blog about fuel in oil http://californiascooterco.com/blog/

[2LZ]

To think all this fuss about a hose on all my bikes I've never paid attention to, because it always just dumped under the bike. On many old HD's, they had two vents. One that dumped and one that you could open on occasion and let it spray your chain.

Best "catch can" I ever saw was an old biker I knew on a Panhead chopper. He had a 50 ml (airplane bottle) Jack Daniels bottle mounted that caught his ventings. We'd pull up to a bar, he'd unscrew it and dump it in a flower pot. He didn't want anyone slipping on his drizzle.

[BlackBike]

To think all this fuss about a hose on all my bikes I've never paid attention to, because it always just dumped under the bike. On many old HD's, they had two vents. One that dumped and one that you could open on occasion and let it spray your chain.

Best "catch can" I ever saw was an old biker I knew on a Panhead chopper. He had a 50 ml (airplane bottle) Jack Daniels bottle mounted that caught his ventings. We'd pull up to a bar, he'd unscrew it and dump it in a flower pot. He didn't want anyone slipping on his drizzle.

2lz, my bike has the little hose off the air box that is perched right on top of the chain
See screwdriver head touching hose from air box PIC OF BASHAN BLAZE BELOW
5963

[rjmorel]

Joe posted that Rider magazine just did a ride report on the 2016 RX3 and it clearly shows a pic with the OCS half full of liquid. Report mentioned that it had grease zerks on the swing arm ? that would be good. rj

http://ridermagazine.com/2016/05/18/2016-csc-rx3-adventure-road-test-review/

[SpudRider]

Joe posted that Rider magazine just did a ride report on the 2016 RX3 and it clearly shows a pic with the OCS half full of liquid. Report mentioned that it had grease zerks on the swing arm ? that would be good. rj

http://ridermagazine.com/2016/05/18/2016-csc-rx3-adventure-road-test-review/

Thanks for alerting us to the nice review by Rider Magazine. :tup:

I have added a link to this review in the RX3 Tech Sticky, under the Ride Reviews subheading. ;)

http://www.chinariders.net/showthread.php?t=14228