Overflow tube issue - Page 3

pyoungbl · 08-17-2016, 10:28 PM

With our 250cc single, I wonder how much pumping action we actually have. I suspect we are not looking at a large volume of air being moved up into the airbox. It's more like a fixed volume being pushed back and forth along the hose going from crankcase to airbox. Of course the vacuum at the air box will suck from the crankcase but it's not going to be a hurricane flow of air in that tube.

I'm still interested in figuring out why some Zongs have high concentrations of fuel in the crankcase, as well as why some have a bunch of liquid in the drain valve. If all had these issues it would be easier to figure this out but some do and others don't.

jbfla · 08-17-2016, 11:39 PM

Quote:

Originally Posted by pyoungbl

With our 250cc single, I wonder how much pumping action we actually have. I suspect we are not looking at a large volume of air being moved up into the airbox. It's more like a fixed volume being pushed back and forth along the hose going from crankcase to airbox. Of course the vacuum at the air box will suck from the crankcase but it's not going to be a hurricane flow of air in that tube......

P, I could not feel any suction from the airbox with the engine running (at idle).

Perhaps at higher rpm, while the bike is underway, some is developed.

On the other hand, when I removed the hose from the engine,(engine running at idle), and put my finger over the crankcase opening, the pulses were readily evident.

P, have you had any resolution of you RX3's fuel in the oil problem?

jb

detours · 08-18-2016, 12:31 AM

There's a lot of math and physics in this article, but I learned a lot about low pressure condensation anyway. Worth a read.

http://www.smcworld.com/docs/technol...ndensation.pdf

BlackBike · 08-18-2016, 12:40 AM

Quote:

Originally Posted by pyoungbl

With our 250cc single, I wonder how much pumping action we actually have. I suspect we are not looking at a large volume of air being moved up into the airbox. It's more like a fixed volume being pushed back and forth along the hose going from crankcase to airbox. Of course the vacuum at the air box will suck from the crankcase but it's not going to be a hurricane flow of air in that tube.

I'm still interested in figuring out why some Zongs have high concentrations of fuel in the crankcase, as well as why some have a bunch of liquid in the drain valve. If all had these issues it would be easier to figure this out but some do and others don't.

Oh God, dare I say it, but is this where break in comes in to play with the amount of fuel getting past worn rings. Every bike is going to vary depending on the course of break in and the eventual milage piston wear. Now we circle back

just shoot me!

pyoungbl · 08-18-2016, 10:12 AM

Quote:

Originally Posted by jbfla

P, have you had any resolution of you RX3's fuel in the oil problem?

jb

No resolution yet. Actually, it has just been too hot/humid for me to ride the bike. Remember, I did a 7500 mile ride in July so I have already had my dose of hot riding for 2016. I installed a 90C thermostat and idled the engine to get all the air bubbles out of the system. I have seen the left radiator get up to 190F (the fan never came on) sitting in the garage. When I get the bike back on the road I hope to see higher crankcase temps than the last time I checked.

2LZ · 08-18-2016, 10:28 AM

Ok....showing my age here. I've never once in my 103 motorcycles have ever had a PCV valve. The dang thing vented to the ground.

Question: Let's just say for grins that this little piston really does create enough vacuum/pressure (like a 350 V8) to require a PCV valve. Wouldn't one want it to be able to pull that vacuum (on the piston upstroke) from elsewhere (say, fresh air) other than trying to pull it past the crank or engine seals?

The most I've seen on a ground vented crankcase vent is a small filter on a motorcycle.
Something to ponder............

2LZ · 08-18-2016, 10:32 AM

Regarding the tube filling up, my first oil change, it filled about half way over the course of riding. Nothing big. After I changed the oil and made sure I put in the exact amount required, my tube has yet to collect any. I think I may have overfilled it the first time....at least that's my thought.

Azhule · 08-18-2016, 11:42 AM

None of my motorcycles had them from the factory either... but a trip to the Auto Parts store fixed that

"Pumping losses" and adding a "Vacuum" to one of the piston strokes is the main reason I add them to my motorcycles...

What happens when you plug a hole and suck the air out of a chamber?!? You create a vacuum... what happens to fluids under vacuum?!? they boil at lower temps... boiling fluids turn to gasses/vapors... gasses/vapors can easily leave your engine out the PCV...

So... let's take your engine with an open Crankcase vent... air/fluids/gasses go both directions constantly... leaving you with tons of raw unburned gas in your oil...

Now lets add a PCV to that Crankcase Vent hole and start the engine... piston goes DOWN, PCV is open letting air/liquids/Gasses/vapors out of the engine, all is happy and working like it should... piston goes UP, PCV is now closed creating a small period of time your engine is now a 'vacuum chamber'... gas now boils at a much lower temp... and just like magic... that gas is turned into vapors and pushed out of the oil/engine/PCV into your air box on the next "Down Stroke" of the piston... little to no fuel contamination in your oil samples... more HP and Torque due to less 'pumping losses' and 'air swirling in the engine'

"All in theory" of course

2LZ · 08-18-2016, 11:47 AM

Quote:

Originally Posted by Azhule

None of my motorcycles had them from the factory either... but a trip to the Auto Parts store fixed that

"Pumping losses" and adding a "Vacuum" to one of the piston strokes is the main reason I add them to my motorcycles...

What happens when you plug a hole and suck the air out of a chamber?!? You create a vacuum... what happens to fluids under vacuum?!? they boil at lower temps... boiling fluids turn to gasses/vapors... gasses/vapors can easily leave your engine out the PCV...

So... let's take your engine with an open Crankcase vent... air/fluids/gasses go both directions constantly... leaving you with tons of raw unburned gas in your oil...

Now lets add a PCV to that Crankcase Vent hole and start the engine... piston goes DOWN, PCV is open letting air/liquids/Gasses/vapors out of the engine, all is happy and working like it should... piston goes UP, PCV is now closed creating a small period of time your engine is now a 'vacuum chamber'... gas now boils at a much lower temp... and just like magic... that gas is turned into vapors and pushed out of the oil/engine/PCV into your air box on the next "Down Stroke" of the piston... little to no fuel contamination in your oil samples... more HP and Torque due to less 'pumping losses' and 'air swirling in the engine'

I'd like to see some oil testing samples of your idea here. That would be interesting.
My only concern would be that the moment of vacuum may play hell on the seals....but if your motors have never puked, then it's probably not a concern. Maybe I just have "seal paranoia" from all of my old 2 stoke days... ;-)

JKR · 08-18-2016, 12:26 PM

Well once again, all great info. I believe I will be pretty much leaveing things alone for now. I had mentioned that I thought I still had fluid making its way into the air box. Not so, it was a very small amount after 50 miles of riding and just was enough to fill the little tiny view tube off the box. I'm thinking it's just residual from when it was being filled with the bad crank case cover seal. As far as the OCV drain tube, I will probably continue to monitor for a while and eventually do the bypass if I deem in necessary and just get tired of dealing with it. Man, I'm telling ya, this site has helped me so much with info on different little things. I know I wont wait so long again to actually post or reply to questions. Thx again

JKR · 08-18-2016, 12:31 PM

Oh yeah, I want to reiterate that I'm an instructions kind of guy. I seldom shoot from the hip on any work I do on my bike or anything. I followed break in, maint schedules to the letter. Adjusted some of the work after learning tweaks and trick from sites like this, conversations with Gerry from CSC and other owners. Not to say I haven't made some minor issues that should have been nothing but lessons learned. I just don't think I've hurt my bike by not breaking in or maintaining correctly.

katflap · 08-18-2016, 01:48 PM

Quote:

Originally Posted by pyoungbl

With our 250cc single, I wonder how much pumping action we actually have. I suspect we are not looking at a large volume of air being moved up into the airbox. It's more like a fixed volume being pushed back and forth along the hose going from crankcase to airbox. Of course the vacuum at the air box will suck from the crankcase but it's not going to be a hurricane flow of air in that tube.

I'm still interested in figuring out why some Zongs have high concentrations of fuel in the crankcase, as well as why some have a bunch of liquid in the drain valve. If all had these issues it would be easier to figure this out but some do and others don't.

There is also blow by gasses to add into the flow.

I have been reading this article on it, though it is talking about car engines I was surprised at how much there is. On my rough calculations using the equation quoted in the article, there could be as much as 1.8 litres of blow by in a 1 minute at idle.

The article here
http://www.106rallye.co.uk/members/d...hersystems.pdf

So i'm going to scientifically test this

by seeing how long it takes to fill up a 10 litre *bin bag , attached to the crankcase breather.

you never know it might just work

* translation for you guys, bin bag = garbage bag

2LZ · 08-18-2016, 03:36 PM

Excellent point on the blow-by katflap, especially as the engine wears and it increases. That wasn't even brought into the equation yet.

My concern about the entire OCS thingy/filter/separator is that once it gets munged up, (if it's installed the 'correct" way), is that it may become a block for the vapors that should be passing back up into the intake....which is a whole 'nuther thing. It's not "eco-friendly", but I'd much rather dump these gasses outward (even filtered) instead of pumping them back through my clean intake and injection assy.

On Mrs. 2LZ Vic, this recirc gunk will puddle in her air box from miles and miles of cruising.....then once a month I'll get on it, bring it to redline in a couple gears and the cloud that comes out the tail pipe when that puddle gets sucked into the chambers is impressive. ;-)

BlackBike · 08-18-2016, 03:43 PM

Quote:

Originally Posted by katflap

There is also blow by gasses to add into the flow.
I have been reading this article on it, though it is talking about car engines I was surprised at how much there is. On my rough calculations using the equation quoted in the article, there could be as much as 1.8 litres of blow by in a 1 minute at idle.
The article here
http://www.106rallye.co.uk/members/d...hersystems.pdf
So i'm going to scientifically test this

by seeing how long it takes to fill up a 10 litre *bin bag , attached to the crankcase breather.
you never know it might just work

* translation for you guys, bin bag = garbage bag

i think the engineers of this bike just intended its owners to be carving a few roads and hitting a few trails with this bike.

sounds interesting

surfndirt · 08-18-2016, 08:20 PM

So from what I've read in this interesting thread... today I removed the OCS and just cut a couple inches off the tube that went to the airbox and connected it to the crankcase. Should be all good, correct?

08-18-2016, 12:31 AM	#33
detours Join Date: Sep 2014 Location: Arvada, CO Posts: 1,004	There's a lot of math and physics in this article, but I learned a lot about low pressure condensation anyway. Worth a read. http://www.smcworld.com/docs/technol...ndensation.pdf __________________ Red 5 standing by! 2015 CSC red RX3 with 19" front wheel, Shinko 804/805, skid plate, tall seat, 13T/45T sprockets, progressive shock, Winyoochanok windshield, GENSSI LED headlight, SW-Motech tankbag, Shorai Lithium battery 2014 Ural Patrol
	0

08-18-2016, 10:28 AM	#36
2LZ Join Date: Mar 2010 Location: Volcano, Ca Posts: 7,080	Ok....showing my age here. I've never once in my 103 motorcycles have ever had a PCV valve. The dang thing vented to the ground. Question: Let's just say for grins that this little piston really does create enough vacuum/pressure (like a 350 V8) to require a PCV valve. Wouldn't one want it to be able to pull that vacuum (on the piston upstroke) from elsewhere (say, fresh air) other than trying to pull it past the crank or engine seals? The most I've seen on a ground vented crankcase vent is a small filter on a motorcycle. Something to ponder............ __________________ "Light a fire for a man, and you heat him for a day. Light a man on fire, and you heat him for the rest of his life." 2007 Suzuki DRZ400S (SM convert) 2009 Q Link XP 200 1967 BSA B25 250cc Starfire 2022 Royal Enfield Interceptor 650 2023 Royal Enfield Scram 411 1948 Royal Enfield Model G 350
	3

08-18-2016, 10:32 AM	#37
2LZ Join Date: Mar 2010 Location: Volcano, Ca Posts: 7,080	Regarding the tube filling up, my first oil change, it filled about half way over the course of riding. Nothing big. After I changed the oil and made sure I put in the exact amount required, my tube has yet to collect any. I think I may have overfilled it the first time....at least that's my thought. __________________ "Light a fire for a man, and you heat him for a day. Light a man on fire, and you heat him for the rest of his life." 2007 Suzuki DRZ400S (SM convert) 2009 Q Link XP 200 1967 BSA B25 250cc Starfire 2022 Royal Enfield Interceptor 650 2023 Royal Enfield Scram 411 1948 Royal Enfield Model G 350
	1

08-18-2016, 11:42 AM	#38
Azhule Join Date: Dec 2015 Location: CO Posts: 1,525	None of my motorcycles had them from the factory either... but a trip to the Auto Parts store fixed that "Pumping losses" and adding a "Vacuum" to one of the piston strokes is the main reason I add them to my motorcycles... What happens when you plug a hole and suck the air out of a chamber?!? You create a vacuum... what happens to fluids under vacuum?!? they boil at lower temps... boiling fluids turn to gasses/vapors... gasses/vapors can easily leave your engine out the PCV... So... let's take your engine with an open Crankcase vent... air/fluids/gasses go both directions constantly... leaving you with tons of raw unburned gas in your oil... Now lets add a PCV to that Crankcase Vent hole and start the engine... piston goes DOWN, PCV is open letting air/liquids/Gasses/vapors out of the engine, all is happy and working like it should... piston goes UP, PCV is now closed creating a small period of time your engine is now a 'vacuum chamber'... gas now boils at a much lower temp... and just like magic... that gas is turned into vapors and pushed out of the oil/engine/PCV into your air box on the next "Down Stroke" of the piston... little to no fuel contamination in your oil samples... more HP and Torque due to less 'pumping losses' and 'air swirling in the engine' "All in theory" of course __________________ "Think as you like... but this self proclaimed Professor is always right" - Buckshot "You never know what someone is hiding beneath their smile..." - NinjaTom - R.I.P.
	1

08-18-2016, 03:36 PM	#43
2LZ Join Date: Mar 2010 Location: Volcano, Ca Posts: 7,080	Excellent point on the blow-by katflap, especially as the engine wears and it increases. That wasn't even brought into the equation yet. My concern about the entire OCS thingy/filter/separator is that once it gets munged up, (if it's installed the 'correct" way), is that it may become a block for the vapors that should be passing back up into the intake....which is a whole 'nuther thing. It's not "eco-friendly", but I'd much rather dump these gasses outward (even filtered) instead of pumping them back through my clean intake and injection assy. On Mrs. 2LZ Vic, this recirc gunk will puddle in her air box from miles and miles of cruising.....then once a month I'll get on it, bring it to redline in a couple gears and the cloud that comes out the tail pipe when that puddle gets sucked into the chambers is impressive. ;-) __________________ "Light a fire for a man, and you heat him for a day. Light a man on fire, and you heat him for the rest of his life." 2007 Suzuki DRZ400S (SM convert) 2009 Q Link XP 200 1967 BSA B25 250cc Starfire 2022 Royal Enfield Interceptor 650 2023 Royal Enfield Scram 411 1948 Royal Enfield Model G 350
	1

08-17-2016, 10:28 PM	#31
pyoungbl Join Date: Feb 2016 Location: Portsmouth, Virginia, USA Posts: 632	With our 250cc single, I wonder how much pumping action we actually have. I suspect we are not looking at a large volume of air being moved up into the airbox. It's more like a fixed volume being pushed back and forth along the hose going from crankcase to airbox. Of course the vacuum at the air box will suck from the crankcase but it's not going to be a hurricane flow of air in that tube. I'm still interested in figuring out why some Zongs have high concentrations of fuel in the crankcase, as well as why some have a bunch of liquid in the drain valve. If all had these issues it would be easier to figure this out but some do and others don't.
	1

08-18-2016, 12:26 PM	#40
JKR Join Date: Feb 2016 Posts: 23	Well once again, all great info. I believe I will be pretty much leaveing things alone for now. I had mentioned that I thought I still had fluid making its way into the air box. Not so, it was a very small amount after 50 miles of riding and just was enough to fill the little tiny view tube off the box. I'm thinking it's just residual from when it was being filled with the bad crank case cover seal. As far as the OCV drain tube, I will probably continue to monitor for a while and eventually do the bypass if I deem in necessary and just get tired of dealing with it. Man, I'm telling ya, this site has helped me so much with info on different little things. I know I wont wait so long again to actually post or reply to questions. Thx again
	1

08-18-2016, 12:31 PM	#41
JKR Join Date: Feb 2016 Posts: 23	Oh yeah, I want to reiterate that I'm an instructions kind of guy. I seldom shoot from the hip on any work I do on my bike or anything. I followed break in, maint schedules to the letter. Adjusted some of the work after learning tweaks and trick from sites like this, conversations with Gerry from CSC and other owners. Not to say I haven't made some minor issues that should have been nothing but lessons learned. I just don't think I've hurt my bike by not breaking in or maintaining correctly.
	3

08-18-2016, 08:20 PM	#45
surfndirt Join Date: Feb 2016 Location: SC, USA Posts: 46	So from what I've read in this interesting thread... today I removed the OCS and just cut a couple inches off the tube that went to the airbox and connected it to the crankcase. Should be all good, correct? __________________ '16 Red RX3, K270's, 13t Front, Fog lights, Tusk Bar Risers (4K mi.) '82 Suzuki SP250 (11k Miles) '85 Honda Rebel 250 (Sold April 2016)
	0