| Author | Message | ||
     Snow_jw |
Just got done with mine a few min ago. | ||
| Motorbike |
Do any of you know what type of pressure we are dealing with in the breather hoses? Is it just a slight positive pressure coming out of the hose or is it a series of positive and negative pulses? If the plastic hose fittings on top of the rocker boxes are one-way check valves, then I guess it would be a series of positive pressure pressure pulses? I was just wondering about riding in the rain with the open breather filter that most are running and if it would actually suck any water in? I would like to mount mine in an area that is covered, at least a little bit. You guys that have just completed the mod, please let us know if anything changed as far as driveability is concerned. Thanks. | ||
| Snow_jw |
I don't know about the uly but I know on the 450 motorcross bikes the YZ450 would suck up water if you killed it in the water then started it up but the line was low on the frame as well. So I don't think the rain would be an issue at all. | ||
| Andymnelson |
It's not NEEDED...but it improves drivability. The positive pressure needs to be vented off somehow, and EPA requires Erik to vent them into the intake for the fumes and oils to be re-burned. When you remove that nasty air and oil form the intake, the engine runs smoother.
This video should answer that question. There is also one of an XB motor out there somewhere...just can't find it right now. No concerns at all about stuff getting sucked in.
That's kinda what this thread is all about  | ||
| Yamafreak |
Did mine today, so far so good.  | ||
| Socrates |
fix'n to get ready to do mine. I have all the parts, just need the time to do it. Maybe after the baby goes to bed tonight or first thing in the morning before she wakes up. Oh the joys of having a 1yr old. | ||
| Swampy |
The re-route is to keep the combustion byproducts and oil vapor out of the intake track where it can gum things up. The plastic vent tubes at the rocker boxes are not one-way check valves. There is a slight pressure, I don't know how much but if it was too much you would have some real leaking problems. You could run the vent tube right to the ground, but some folks are just very anal about little bits of dirt crawling nearly 3 feet UP a hose to contaminate the engine. In the old days before the EPA every engine had a thing called a Road Draft Tube that allowed for the crankcase to vent to atmosphere. Some of those had little bits of a filter like a metal scouring pad stuck in them to filter the vent tube. | ||
| Motorbike |
I noticed a lot of you are using worm gear type hose clamps to secure the hose to the barbed fittings. If you are using a 3/8" hose on a 3/8" barbed fitting, there really should be no need for a clamp at all because this system should never build up any amount of pressure, unless the filter is plugged, right? Also, a standard plastic 3/8'"T" fitting made for automotive use should work to join the 3 hoses together up near the throttle body, shouldn't it? I doubt it would melt but that is just my opinion. Final question: Some of you have installed the filter before the catch can, others install if after the can. Which way is correct and why? Thanks. | ||
| Rwcfrank |
Mike your right about the tee being plastic but I used brass near the rocker covers only due to the heat causing the plastic to break over time from getting brittle. I use safety wire for my hose clamps rather than tie wraps or worm gear hose clamps. As for the plumbing think about this concept. You want air to flow out of the system and any liquid that may collect should either drip into the catch can or run onto the ground. You could just run the hose out the back with no filter as many have done. I am leaning towards that now. My current setup works perfectly except for the minor odor emitting from the filter near the front of the bike | ||
| Balloyd66 |
I see where the positive pressure occurs when the engine is running, but do you think when the air in the engine cools it will develop a negative pressure? Don't think it'd suck up a cockroach or anything, but would be an interesting experiment to do sometime. If you stuck the open hose in a glass of water while the engine was cooling, what do you think would happen? Just how much suction would the cooling air in the engine create? Hmmm. | ||
| Motorbike |
Rwcfrank, I think your idea of using a brass "T" is an excellent one for the reason you gave. No use trying to save a penny on something that could cause a breakdown later. Plastic cannot take the heat very well, as you said. Balloyd66, I just came in from the shop to see if anyone replied to my last questions. I just started on the breather mod and decided to find out if the plastic elbows that attach the breather hoses to the rockerbox are actually a one-way check valve or not. I was not able to blow into either hose at all but was able to suck air out. ( I would not recommend this if you plan to kiss your wife or girlfriend anytime soon! ) This proves they are definitely check valves and air can only flow out of the rockerboxes. So, to answer your question, I don't think this system would allow anything to be sucked up into the engine. Thanks. | ||
| Iliad |
I agree that brass is better than plastic for very hot applications. On the other hand, nearly everything in that airbox is plastic. Just sayin... | ||
| Ourdee |
I used a light weight brass T and small plastic wire ties instead of worm gear clamps. Oh, Here is the original XB balloons: Breather Bypass, balloon, no catch-can, at start-up, on idle 5k rpm then down to 3k rpm and pop | ||
| Yamafreak |
plastic, no clamps,filter,can no problems! Bike is better down low. | ||
| Motorbike |
I did not have time last night to finish my breather mod and may not today as I am working OT at my real job. But, I did get a start on it. As I took things apart, I was looking at the location of the Intake Air Temp sensor. I wonder if the location of this piece isn't causing more problems than the hot vapors and spooge going down the intake? The IAT sensor is right next to the stock location of the breather hoses, inside the air filter. Seems to me that the hot air and vapors from the breathers could be heating up the IAT sensor, which in my opinion would cause the ECM to lean out the mixture. Has anyone tried re-locating the IAT sensor to a different, cooler place and if so, what were your results? It just seems to me that if the IAT sensor was in a cooler area, the ECM would fatten up the mixture slightly and my bike would not feel like it is always slightly on the lean side. Any thoughts on this? I know it is actually supposed to sense the temperature of air going in but maybe we can fool it? I have to admit, I spent at least an hour last night trying to figure the best place to mount the breather filter. Some people have complained of smelly fumes when the filter is mounted up front near the engine. I thought about mounting it back under the seat near the power outlet socket but figured it would leave an oily mess back there. Still not sure where I am going to put it. Please bear with me, I know I am making way too big of job out of this! Thanks. | ||
| Rwcfrank |
Motorbike, I started this thread after doing the mods on my bike. I havr decided to eliminate the filter and run the hose back to the swingarm. I dont do deep water crossing and I can't see anything getting the hose. I may put some pcv foam in the hose to slightly filter the air, I will let you know how that turns out. | ||
| Dmmblaze |
I'm gonna take you up on that one of these days Andy. I've been wanting to see a Uly with 1125 mirrors on it for awhile now. | ||
| Dmmblaze |
This talk about the EPA has me wondering how legal this mod is. If every motorcycle in the US was to do it, how much of an environmental impact would the sludge produce? Small DW horizons roaming the land...A small leak can sink a great ship... over time... just musing... | ||
| Motorbike |
Rwcfrank, I was thinking about doing the same thing except I would use a small in-line gas filter from a lawn mower somewhere in the line that goes to the swingarm area. Dmmblaze, I was wondering the same thing. I am going to just keep this real simple the first time and if it really makes any difference in performance, I may do something to make it look nicer. If a catch can is used and the spooge is disposed of properly, then the only thing that would be going into the air is the slight amount of vapor that comes out of the filter. I'm guessing that your average lawn mower pollutes more in 10 minutes than this mod would on an all day ride. Just my thoughts. If the mod actually makes a noticeable difference in low end performance, than I guess my desire for that will outweigh my desire to satisfy the EPA. Thanks. | ||
| Blasterd |
I've done many breather re-routes on my bikes and other buddies bikes. if you want to keep it simple you can tee it off and run it down the frame to the back of the bike. If you don't want it to drip plug it but just remember to dump it weekly, the length of hose is enough to store the spooge for days. As far as filtering it, when it comes down the frame y it off and go back into the airbox with a hose, the air filter is now your filter. You can go elaborate and order a nice catch can, I bought a Jaz and modified it to work on my CityX and had Outerwears mane me a cover for the little K&N. Just my 2 cents! As far as the Uly, I have not done it yet but I'll get to it.... | ||
| Andymnelson |
simple solution for the smelly fumes: drill a hole in the air filter baseplate (outside of the air filter, therels lots of room front left of the air box), run your filter hose up through it and mount the filter inside the airbox. The stink will get reburned,the oil and spooge will go to the catch can. this is what I did on the XB9S, and what I will do with the Uly once I get my catch can back from anodizing! | ||
| Whisperstealth |
Ditto yamafreak, only I used 5/16 fuel line. I used it because I had some line and T's left over from a "Y/T" mode I did on the KLR. Only used one T, ran along frame, dumps behind rear peg. Simple, no extra $ =  | ||
| Tootal |
The one way valves on the rocker covers are a pcv valve,(positive crankcase ventilation), just like your cars. They allow pressure out but nothing back in. Your engine runs in a vacuum this way and this has many performance benefits. The pressure released is very small. I used a plastic T, no clamps and ran it out the left swingarm right next to the fuel tank breather hose. No filter, no catch can and no drips on the garage floor. The bike ran smoother and all is good for many miles. | ||
| Motorbike |
Andymnelson, Your idea sounds like a real good one but isn't it kind of defeating the purpose of what we are trying to accomplish in the first place? As I understand it, the idea of re-routing the breather is to prevent hot oily vapors and spooge from being sucked down the intake. Your idea removes the spooge but it seems that hot air and oily fumes will be going back into the intake. I completed my breather re-route last night and rode about 150 miles in hot weather today. The bike actually ran better at low RPM's than it has since new. The only negative part I have noticed so far is a faint hot oil smell when sitting at a stoplight for a while. I have my breather filter mounted directly under the left side scoop but I will be willing to try your idea with just a little more convincing. Thanks.   | ||
| Andymnelson |
In theory, yes you are correct. In practice, this method works very well! I mounted the filter outside of the air filter, and I would imagine that the air coming out of it has a negligible amount of contaminants in it....especially once it passes through the small K&N filter and then through my K&N air filter. It worked great on the XB9S anyway! | ||
| Surfsofa |
Motorbike, how on earth is that bike so clean? Does it ever go outside? I'm not sure my bike was that clean on the day I bought it (new)!! | ||
| Motorbike |
Andymnelson, I think I will try what you recommend. If I don't like it, I can easily switch it back. Thanks for the idea! Surfsofa, I will take that as a compliment so thank you. My bike is my toy which I use mostly just for recreation, not as a daily driver. I usually drive my car or truck to work so I don't put many miles on the bike. I bought it in Nov.2009, it sat in my workshop with a cover on it through the Minnesota winter and as of right now, I only have 3400 miles on it. Thanks. | ||
| Matchanu |
Andymnelson; That theory is actually a pretty good idea, negative pressure will pull the case gases out, any condensation will flow down the tube/hose, and any oil mist will only help your K&N filter. I just fitted my bypass today, but I may try that idea later. I put a small petcock drain on the end of my line for easy drainage, but after reading that it's a one way valve on the PVC end on the heads, may just open it up. | ||
| Andymnelson |
Yes that was the thought. Regardless of the installation, the filter should be highest point of the system...or it should come off of a catch can so that the oily air is not just running straight to the filter. I see too many of them with the filter in the middle, or pointing down...those will fill up with oil and drip eventually, and will certainly be less effective at flowing air as they oil up. I don't mean any of this to belittle anyone! I'm just pointing out the thought that has gone into designing a system like this. | ||
| Motorbike |
Matchanu, I think you will need to leave the petcock on the end of the drain tube, won't you? If that is open, you will have an open line all the way back to the check valves in the rockerboxes. If you do that, then the filter would not be necessary. Please feel free to correct me if I am wrong about this. I have been wrong before. Andymnelson, I have my filter pointing down as you mentioned but the hose to the filter actually goes up and over the ignition coil and back down to a "T" in the hose that runs to the catch can ( clear tubing ). The "T" faces up so no oil actually runs down to the filter but over a long period of time, there may be a little oil buildup from the fumes. I have only put about 200 miles on the system so far. I still like your idea better and plan to use it but if my wife catches me working on the bike again, she might have me committed. I just need to find a time when she is gone for about 45 minutes! Maybe I could send her out shopping? Thanks. |
