Re-route hoses

[Defender88]

ok the hose circled in red just goes up near my oil cooler.. apparently the previous owner attempted this mod but idk if its done right

there is also a hose coming from the crank case that goes up near the shock. do i connect these two lines with the little filter?

 

[Stevenc150]

Looks like it's done. He just decided not to use the little air filter in-line for venting. Some have used that method with no problems.

Only thing is I didn't want the "stuff" coming out of the hose and dripping/blowing up under my bike on the muffler or rear tire. That's why I ran mine to the rear and up and under the footpeg. Course you could put a plug in the end and drain as needed leaving the mod as-is.

 

[Defender88]

well I am going to add the inline filter and catch can. the hose coming from my crankcase... does anything get done with that?

 

[Defender88]

well mine still has the hesitation and sputtering at low RPM. I added a catch can and am waiting for napa to get in the filter. hopefully this will help some.

 

[nativeXb12Rbuell]

Baal your first ?; the filter is to vent those gases to the outside of the crankcase and yes to prevent any debris from getting sucked into the rocker cover (valve cover).
maybe i dont understand your second Question but, without a filter to let the gases ESCAPE from the crankcase or vented back into the air intake to be burned in the combustion chamber,, it would build up excessive pressure in the crankcase and also cause poor idle , it is a pcv valve just like on your car either vented to the outside atmosphere or vented back into air intake (pcv valve uses vacuum from the intake manifold to draw the fumes from the crankcase).the thing is that the oil mist and any condensation is suposed to drain back and return to the crankcase through oil passageways in the cylinder head, That's how it 's designed to work , but if they are fine enough ( small enough atomized) the they flow with the gases from the crankcase up through the hose and back into the air intake to be burned in the combustion chamber,( this for EPA emissions regulation to keep crankcases gases from causing any air more pollution but those crankcase gases dont burn very well and is not ideal for your engine to operate at its best , and the burning of thoses crankcase gases and the oil mist and condensation has an effect on how well your engine runs and causes it to actually get bad fuel ecomony ) or if you have this mod the gases escape to the outside of the crankcase and the oil and condensation flow from gravity to the catch can or drain . with this mod there is no real vacuum pulling the gases from the crancase just vented to the out side air presure which is less pressure than in the crankcase and /or rocker covers there for it vents the gases to the outside atmosphere air.

 

[nativeXb12Rbuell]

from the service manual:
Crankcase Breathing System ,see fig.3-114. Presure created in the flywheel area on the piston downstroke is released through the REED VALVE into the gear case. From there a mixtre of crankcase air and oil mist is vented up the push rod covers to the upper rocker box(top of head).
see fig.3-115. Air is allowed to escape the rocker boxes by exiting the postive crankcase vent(PCV) valves(4)
locatedon top of the rocker boxes (top of rocker cover/valve cover).From the PCV valves the air enters the crankcase breather hoses(2,& 3). The crankcase breather hoses route through the air cleaner base plate (1) to the air box where it isdirected inside the air filter element and back into the engine. the oil mist collects and eventually returns to the crankcase through oil passageways in the cylinder heads. that how it is originally designed to work. maybe that might help you understand it somewhat better. see figures below..

 

[nativeXb12Rbuell]

odo2451 i like your filter and catch can combo , where did you buy that at ?

 

[Stevenc150]

the hose coming from my crankcase... does anything get done with that?

Is the hose your talking about not in the pics you put up?

Also, I'd take some length off of hose #3 and swap hoses #1 & #2. Hose #1 looks like it might be crimped close (or maybe it's camera angle).

 

[Defender88]

I did shorten those up some but I didnt read this post before i put the bike back together so I didnt get a chance to switch 1 and 2. on the side of the engine, just above the foot brake there is a 3/8" hose coming directly out of the crank case, it goes up near the airbox then under the seat and is zip tied to my rear spring

 

[Defender88]

overall this made no difference

 

[Defender88]

Will adding the filter make any difference or is it just being open ok?

 

[Stevenc150]

That's a point of argument. Just to be safe and I thought it looked kinda cool, I put one on mine.

If I remember right, mine has the crankcase hose zip-tied to the shock too. I'll have to check. If it is, they come from the factory like that since nothing was done to mine until I got it. Either way, this mod doesn't involve that particular hose.

 

[nativeXb12Rbuell]

with the hose from breather mod is left open with no catch can it will eventually leak the oil mist and condensation from the crankcase gases and leak all over or below where ever it is tied to , . plus it leaves the Possibility of something like bugs or dust getting up into the rocker boxes, a catch can and filter will prevent that. if the hose is capped off or plugged up without a filter to let the gases escape or vented back into the air intake, it would build up excessive pressure in the crankcase and also cause poor idle.

 

[Defender88]

right now mine has a catch can and is T'd from there with a long hose running down the side of the bike to my swing arm. this mod has not helped with the low RPM stutter

 

[Defender88]

well instead of the long hose running down to the swing arm I just stuck the filter on the T. here is what it looks like but still no benefit from doing this mod, does it take a while to notice it?

 

[dallasb]

When i did the reroute on mine I noticed it right away. I have an xb9 but it helped tremendously with the low end surging. I can lug the bike down to around 1900 before it starts to buck like it used to at around 2900.

 

[Defender88]

yea mine does not run like that at all. I dread going into a parking lot to search for a spot, im in 1st gear feather the clutch and revving the engine. agghh

 

[dallasb]

Defender are you sure that the hose isn't kinked somewhere?

 

[Defender88]

i just redid the hoses and i rode for about 20miles,no difference in the ride but a small amount of stinky oil/water in the catch can

 

[nativeXb12Rbuell]

double check hoses for kinks or cloged in the hoses, or clogged pcv valves on top of the rocker boxes . and the holes in air intake plate next to the air filter that you plugged up for the mod check them to make sure there not leaking unfiltered humid air(or lots of moisture) into intake, but would cause more problems than the rough low rpm.