For those with pods - what to do with breather hose?

[Steve]

... I don't want even the chance of blowby vapors from my 28 year old motor of getting in my carbs. ...

My opinion is that if you have that much blow-by, you have other things you should be worrying about. In a healthy engine, there will be very little coming through that hose.

My son's 650 is the only bike we have with pods, I put a longer hose on, much like you did.

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[cableguy]

My opinion is that if you have that much blow-by, you have other things you should be worrying about. In a healthy engine, there will be very little coming through that hose.

My son's 650 is the only bike we have with pods, I put a longer hose on, much like you did.

.

That's true, I guess my choice is based more on preference on than thinking it's the ONLY way to do it. Plus it's just easier

 

[wirelessguy]

Looks like my last post didn't make it up here.

I'll summarize.

I do intend to do something other than feed it back into the carbs but my point was that it is likely not unhealthy and the vacuum caused by the carbs may even be beneficial to the overall vacuum/timing for the crank.

Way I see it there are three options other than leaving the hose dangling.

1. Install a PCV Valve (but I'm not sure about the right size for my 1100E, nor do there seem to be any dimensions on these online, just replacements for ones that have cross references to original parts).

There's an interesting video for a KLR650 I found here: http://car-mods.wonderhowto.com/how-to/modify-pcv-kawasaki-klr650-243655/

2. PCV Valve plus Air filter.
Example: http://www.ebay.com/itm/Yamaha-XS65...Parts_Accessories&hash=item3a7899c769&vxp=mtr

3. Valve, filter and canister
http://www.ebay.com/itm/CHROME-EBOC...Parts_Accessories&hash=item4d0395400a&vxp=mtr

Since I don't get a lot of junk coming out of my crank I feel that for me the canister is overkill.

I think I'm going to opt for #2 above but it's only about $10 in parts at the auto store, so I don't think I'm gonna shell out $40-$50 for his kit.

 

[Steve]

If I remember correctly, an automotive PCV valve requires a direct connection to an intake manfold to work properly.

I don't remember exactly when it opens up, but it has to do with vacuum levels. There are times that it is closed and other times that it is open.

The only problem with using a PCV valve is that each cylinder has its own runner, so adding a PCV valve would have affect just that one cylinder. Since it is downstream of the carb, any time the valve is open, it would lean out that cylinder ONLY. On a car, there is just one carburetor (back in the old days) that feeds a manifold. With fuel injected engines, the PCV valve would still be in a common manifold, between the throttle body and the intake runners.

I don't think that a PCV valve (with or without a filter) is the answer.

The canister idea is actually the more-practical one.


There is not a lot of vacuum in the airbox where the hose used to mount. The only vacuum level there is due to the restriction of the air filter, which might only be a problem at full throttle (maximum airflow). Any air flow in the breather tube is going to be due to a very SLIGHT pressure in the crankcase (I don't think it would be enough to measure), and any oil in the vapor is supposed to be caught by the mesh filters in the breather cover on top of the valve cover. What's left going through the hose should not cause any problems for the carbs, as it will be greatly diluted with all the incoming air from the filter.

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[wirelessguy]

I'm not sure I understand the "each cylinder has its own runner comment"?
On our bikes, aren't we talking about a singular OUT from the Crankcase?

I'm still at a little bit of a loss about what I should be doing 'to dangle or not to dangle'. So far I've yet to see any data about something pulling vacuum making the bike operate more smoothly but for some reason I guess the theory sounds like it could make sense.

From your perspective, why is the canister any better (from a vacuum perspective) than just the breather and filter?

If you think the breather won't 'activate' on the bike that is obv a good question I think.

Thanks.

 

[5150/gs]

the thing is oil is heavy,with the original setup it drops into the airbox nd drains,if a plumbing setup like i did to the pods it adds suction and drops the oil itself to the bottom of the pod oiling it.
It actualy worked very well and cured 99% of the oil leaks i had in doin this.It is behind the side panels on the gs1150 so no biggie to me.I thought it ingeniouse hehe.

 

[ben2go]

Here is my set up and I have no issues with oil blow by.However,a good cross wind will cause my carbs to act up with the K&N lunch box filter,RU2970.I was once caught in a wind venturi effect between buildings.I was sitting at a red light.Every time a wind gust came through,my bike shut down like it was running out of fuel.Luckily,I was on a bit of a slope and rolled out into the intersection to restart.After scratching my head and riding in the wind with the bike acting up,I finally figured it out.

K&N 16-1320

 

[5150/gs]

i tried the same thing but anywhere the case seal was weak it leaked oil.i will take a pic n post what i did,it worked great

 

[loud et]

the thing is oil is heavy,with the original setup it drops into the airbox nd drains,if a plumbing setup like i did to the pods it adds suction and drops the oil itself to the bottom of the pod oiling it.
It actualy worked very well and cured 99% of the oil leaks i had in doin this.It is behind the side panels on the gs1150 so no biggie to me.I thought it ingeniouse hehe.

do you have a link to this pod plumbing? curious.

 

[5150/gs]

yuppers,had to upload here it is,cured 99% of my oil leaks at weakspots due to crankcase pressure.compression tests good,i don't use oil between changes,1500 mile,this was mu concoction cure if u may lol.

 

[5150/gs]

not pretty but it works

 

[loud et]

not pretty but it works

Just a four way splitter with tubing. nice.
I recall someone mentioning this in a thread about a one way crankcase pressure valve. It may have been you. The valve was like 100 bucks and I would prob never spring for that. This is a nice alternative. I dont know why it intrigues me so much
My breather tube does smoke lightly, I am just at about 500 miles on my rebuilt engine and I think it is going away. If I do this mod, I will surely post my results. Lower crankcase pressure= less backpressure on pistons and removing crankcase pressure. Fixing small current leaks and maybe preventing future ones. I love it.
My hose is currently just "hanging out" as I have pods. I am not sure what I will do yet. Always something to fiddle with thanks5150

 

[ben2go]

Weird.I've never had a motorcycle that built up enough crankcase pressure to leak or even put oil out the crankcase vent.Sure there will be a very light mist from all the spinning internals,but nothing bad enough to form droplets.

 

[5150/gs]

U see i believe a p.o had my cases apart once,and did not seal it well enuff on reassembly,hence my leaks.have 1 left i cannot cure,going to split cases this winter and seal it up propper,all new gaskets n i will know whats inside and know more about my engine.But this setup i did helped greatly,and it cost me 4.85
But it was not me about the 100 dollar thingy,i woudl never spend that kinda money for something like that,too cheap to much enginuity here.

 

[gustovh]

I am an old cheap retired guy. Used the oem hose, wraped 14" filter felt around the open end of the hose and zip tied it on. No mess no fuss and cleanable.
V

 

[Chuck78]

resurrecting an old thread here, as I feel it is still very pertinent.

normally my engine would behave pretty well if I can ride normally, but a vintage 4cyl bike just tempts me far too much to twist that throttle open quite a lot...

I noticed when I am on spirited rides out in the hills (i.e. riding aggressively our in the best Appalachian twisties I can hit in a day trip from home in SE Ohio & sometimes into West Virginia), I always come home with oil mist all over the undersides of the bike. this does a great job in preserving everything, making sure it will not rust/corrode, but makes for quite a messy bike. Rear tire traction is also a concern.

I started noticing that race bikes quite often had some sort of makeshift catch can. This is when I really started paying attention to this mod.the guy actually gave me a PVC catch can that was fabricated for his race bike when he parted it out. getting my bike ready for the riding season, I clean a whole lot of oil grime from the undersides of it, and so I referred back to this thread.


I currently just have a K&N breather filter on the end of the hose, and had it sitting on top of my air filter, so drips would just hit my K&N dual oval pods. I've still got a lot of misting out all over.


one of my first thoughts was just to get a bunch of fittings and connect all of the carburetor sync ports together with a brazed copper tube manifold that I would fabricate, so that I would have a constant vacuum on the crankcase. any moisture Vapors would get sent out the exhaust, and I don't think it's a problem to introduce minor amounts into the cylinder, as humid air gets sucked in there all the time. this might lead to a little exhaust smoking under aggressive riding, and could also maybe dirty the spark plugs up a little bit unless you are already running on the lean (hot) side.

with the factory set up, I noticed there is a drain hose on the bottom of my 77 GS 750 air box, and the oil would potentially just migrate down into the bottom if there was any condensation forming into liquid again. Vapor mist would of course get sucked into the carbs.

you probably wouldn't want to vent all of the vapors into one pod, as you would have uneven running conditions. it would be even worse if you vented it into only one synch port, as you would then have unmetered air going into that cylinder


the $45 Krank etc copy one way check valve is an interesting concept, and I am going to look at that KLR forum link in a minute. it seems like it from might quite possibly allow the engine crankcase to operate in a vacuum (reducing potential oil leaks and pressure against the pistons & possibly reducing blowby), as it will expel excess pressure, and then when the pressure drops, close itself, sealing the crankcase off into a slight vacuum condition. this would not help the oil migration out of the breather filter, but this seems to be a big positive if you are not running the hose into the air box or pods or synch ports

 

[Chuck78]

These $45 billet aluminum catch cans on eBay from China would be a good basis to make something really trick looking, but I only see one hose thread connection. More work would be required. Also the orientation of the tank looks to need mounted horizontally.

I think I would possibly modify this to mount it vertically and maybe even put a sight glass in it like the fancy car tanks that are larger.

I also thought I could probably pretty easily fabricate something out of one inch or 1.25 inch copper pipe and fittings. That would look pretty trick, definitely home-brewed looking, but much better than PVC

 

[Chuck78]

For $50, if you run pods and don't tap your vent back into the carbs or synch ports, these seem like an excellent idea. The name brand units are about $90-something. This is an "Asian" piece... In theory it should allow to vent off excess pressure without ever sucking more air back in, so it will run a reduced crankcase pressure and cause less blowby, and less oil seepage.

HARLEY, S&S, ULTIMA OR CUSTOM V-TWIN SIFTON CRANK CASE VENT VALVE (PCV)

No need to pay for the higher priced vent valves (Krank, Spyke, ET, Hayden) - get the same functionality from this generic version at a better price

No power gain claims here - just a great way to reduce the pressure inside your engine cases

Only passes air in one direction - put one in your vent line to create a lower internal case pressure

Helps reduce leaks around gaskets caused by higher internal engine pressure

Lowers back pressure behind the pistons for smoother running and less blow-by

Two 3/8" hose barbs - Includes two Gates type hose clamps - Overall length 3", diameter 1-3/8"

PLUS, ONLY OURS COMES WITH AN EXTRA REPLACEMENT UMBRELLA SEAL!

http://www.ebay.com/itm/CASE-BREATH...OVELHEAD-PANHEAD-TWIN-CAM-KRANK-/331797342195

http://www.ebay.com/itm/SIFTON-CASE...HOVELHEAD-PANHEAD-TWINCAM-KRANK-/331788075461

Unlike the automotive type, these can be disassembled for cleaning, great for wet sumpers

Put the "seam" on the engine side

Easy Installation - Nice Chrome finish

Sold Each - Asian Import

See the last picture for the breather check valve used in conjunction with the EBOC oil collector/reservoir - sold separately

 

[Guest]

Maybe I'm missing something, but as I understand it in a GS motor - four or twin - there are as many pistons going up as down, so if the piston seal were perfect there would be no need of a breather. How can you generate a suction without something to suck? A one way valve in there is going to have hard time finding any flow going anywhere but out.

Motors like singles and opposed twins have big venting problems and +/- pulses but inline fours and 180 degree twins don't. So how would air get sucked back in if there's no suck? I can see how the pressure would fluctuate but what would make it go negative?

 

[ben2go]

The rotating mass and heat builds pressure in the crankcase which must be vented.When using a positive crankcase ventilation system (PCV) with a catch can,the catch can, can be put under a vacuum using a T fitting between the carb filters, or intake boots, to create a slight vacuum in the crankcase through the hose connected to the engine's vent fitting.Race engines have been using this set up for a very long time.My racing karts used the same set up.Very simple system to help the engine run a little better and cleaner.