Breather Hose Re-Route ?



13 replies to this topic
  • TeamScream

Posted October 13, 2001 - 05:23 PM

#1

I have heard other people do this but I wanted to be sure I was doing the right thing here....
I am sick of oil puking on my footpeg area and so I routed the oil breather hose up to the air box. Now I placed it on the bottom part of the airbox where the little clear plastic hose that is sealed at one end *was* and the breather fit PERFECT in this place so it seems like the logical position and location? is this correct? also does the oil that normally pukes out just get run through the engine now? has anyone had ill effects doing this?, and finally if this is NOT where it should go...where SHOULD it go?
Thanks!

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01' WR426,YZ timing,EMP #2,#48Pilot,#100PAJ,#175 Main,BK mod,Kouba T-Handle,YZ pipe, open airbox,Gray-Wire Pulled,K&N Filter, throttle stop mod,CA Street Legal,Pure SuperMotard 17 in. wheels, 15/46 gears,ProTaper bars,

  • BlueThunder

Posted October 13, 2001 - 05:51 PM

#2

Route the hose to the ground with the rest of the carb hoses unless you want the oil that's puking on your peg to puke into your airbox. The clear hose at the bottom of your airbox is there to determine if water has entered your airbox. Comes in kinda handy to check for water after a river/stream crossing or after a bike wash and is an easy way to empty the water also. If you're worried about sucking water into the breather
when starting put a piece of oiled foam in the bottom of the extension.

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Y2K WR400FM,Answer top tree w/Accu-Trax clamp,Pro-Tapers(CR-Hi w/ EE handguards),Devol Rad. & frame guards, Guts tall soft foam w/ ballistic cover, 14/52 w/DID VM X-Ring, Kouba-T,Michelin M-12's ft.& rr.,12 oz. flywheel weight, Zip-Ty Racing Link & Shark Fin(plus everythhing else cool that Ty offers), Cycra front rotor guard and T.M. Designworks Chain guide, buffer & chain wheels. Street legal except for the non-"DOT" tires.

  • darbsitton

Posted October 13, 2001 - 06:42 PM

#3

I would not insert the hose into the bottom of the air box. You will eventially get some water in the airbox, and that water and grime could be sucked into the engine

I routed my hose up behind the throttle side radiator and stuck a filter on the end of it, with an aerosol can cover over the filter to provide a little protection from elements/washing.

This was adapted from a post in the archive where a member did the same thing but put it behind the number plate. Air breather filters were available at my local bike shop, just had to get the right size to fit the air breather hose.

Easy mod, costs <$10.

  • TeamScream

Posted October 13, 2001 - 07:39 PM

#4

Ok but Keep in mind this bike NEVER see's the dirt, and therefore will never see the water, it is a SuperMotard machine now and I use it exclusively as a training aid for my road racing career, the bike is set up to allow maximum cornering speed on the pavement and to allow for smooth controlled slides aslo on pavement, so with that in mind are there any other reasons (besides the water issue) why the hose should NOT be routed to the "water indicator" fitting on the bottom of the airbox ?

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01' WR426,YZ timing,EMP #2,#48Pilot,#100PAJ,#175 Main,BK mod,Kouba T-Handle,YZ pipe, open airbox,Gray-Wire Pulled,K&N Filter, throttle stop mod,CA Street Legal,Pure SuperMotard 17 in. wheels, 15/46 gears,ProTaper bars,

  • BlueThunder

Posted October 13, 2001 - 09:11 PM

#5

Sorry Scream...didn't notice that your ride was an SM set-up. I'm sure that sustained high RPM's that you'd run on the track make that unit spit a lot of oil. Still not sure if I'd route it to the airbox though, IMO. I'd personally route it to the atmosphere simply because it can't be a good thing to vent hot, oily vapor into your airbox. Just my opinion.

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Y2K WR400FM,Answer top tree w/Accu-Trax clamp,Pro-Tapers(CR-Hi w/ EE handguards),Devol Rad. & frame guards, Guts tall soft foam w/ ballistic cover, 14/52 w/DID VM X-Ring, Kouba-T,Michelin M-12's ft.& rr.,12 oz. flywheel weight, Zip-Ty Racing Link & Shark Fin(plus everythhing else cool that Ty offers), Cycra front rotor guard and T.M. Designworks Chain guide, buffer & chain wheels. Street legal except for the non-"DOT" tires.

  • DOC

Posted October 13, 2001 - 10:51 PM

#6

im not exactly sure of how much oil and oil fumes are actually passed through the breather hose, but if it is substantial, then you do not want to run the breather hose into the air box. The reason is that the fumes will contaminate your incoming air and therefore your air fuel mix. From what i remember, it lowers the octane of the fuel (octane being the resistance of the fuel to 'knock') and will premote detonation in some engines. This probaly wouldn't be an issue for your bike, but for highly strung turbo charged engines, the issue is very important.

  • BlueThunder

Posted October 14, 2001 - 02:47 AM

#7

My point was that plumbing a hose that releases hot air(inevitable, given the fact that it's being released from the top end of a performance engine) and oil vapor (the oil slick on TeamScreams peg is testament to this) into an airbox attached to a carburetor
drawing said air back into an internal combustion engine system could not be an attribute to the engines performance, given the fact that drawing cool, dense air into an engine is always better for performance than drawing warm, contaminated air. Furthermore, it seems to me that the oil vapors from the breather would initially cause a richer fuel condition, since they would be somewhat combustible, but would eventually cause a leaner fuel condition as the oil accumulated in the air filter and restricted the airflow. Just my opinion. Anyone care to expand or comment on this theory?

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  • MX_Tuner

Posted October 14, 2001 - 03:59 AM

#8

I wouldn't worry about the temp of the air going into the airbox as long as it was tuned for. The amount of oil that might accumulate there may be anohter issue. One thing that may be contributing to the amount of oil getting spit out is the method for checking the oil level. If you do an oil change and fill it to the top mark on the dipstick, it'll be overfull when the engine (and the oil) temp are at running temp. Due to the expansion of the oil, I fill it to the low mark on the dipstick. Once the engine and oi reach normal running temp, the oil expands to the full mark.

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MX Tuner

  • BlueThunder

Posted October 14, 2001 - 04:20 AM

#9

Also important to not screw the dipstick down to check oil level, per manual instructions...."Note: When inspecting the oil level, do not screw the oil level gauge into the oil tank. Insert the gauge lightly."
MXTuner....why not tune for optimum air conditions and not screw yourself over by intentionally plumbing the hot air into the airbox in the first place. Just my opinion.

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Y2K WR400FM,Answer top tree w/Accu-Trax clamp,Pro-Tapers(CR-Hi w/ EE handguards),Devol Rad. & frame guards, Guts tall soft foam w/ ballistic cover, 14/52 w/DID VM X-Ring, Kouba-T,Michelin M-12's ft.& rr.,12 oz. flywheel weight, Zip-Ty Racing Link & Shark Fin(plus everythhing else cool that Ty offers), Cycra front rotor guard and T.M. Designworks Chain guide, buffer & chain wheels. Street legal except for the non-"DOT" tires.

  • TeamScream

Posted October 14, 2001 - 04:33 AM

#10

Ok well I am gathering that the general concensus is NOT to run the hose to the airbox, and since i am going to the canyons today for a fairly hard thrash I am gonna get out there and run it back down the side to atmosphere like it is stock untill I can get a better re-route solution...probably a small filter or something and then route it up under the number plate area as Clark did eh?

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01' WR426,YZ timing,EMP #2,#48Pilot,#100PAJ,#175 Main,BK mod,Kouba T-Handle,YZ pipe, open airbox,Gray-Wire Pulled,K&N Filter, throttle stop mod,CA Street Legal,Pure SuperMotard 17 in. wheels,Braking 320mm "wavy" front rotor, 15/46 gears,ProTaper bars,

  • TeamScream

Posted October 14, 2001 - 04:38 AM

#11

On another note however, Cars used this very solution and many still do, by running the valve cover vent (breather) to the air cleaner via a PCV (positive crank ventilation) valve, my only concern now that I think it through would be the fact that the airbox would generate a substantial low pressure condition and therefore tend to draw more air/oil vapor out from this hose if it were routed to the airbox, but then again with the airbox lid removed and the hose vented to the lower portion of the box itself there would be very little (if any) *suction* happening to the breather hose itself one would think?

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01' WR426,YZ timing,EMP #2,#48Pilot,#100PAJ,#175 Main,BK mod,Kouba T-Handle,YZ pipe, open airbox,Gray-Wire Pulled,K&N Filter, throttle stop mod,CA Street Legal,Pure SuperMotard 17 in. wheels,Braking 320mm "wavy" front rotor, 15/46 gears,ProTaper bars,

  • mcarp

Posted October 14, 2001 - 05:06 AM

#12

Teamscream-

Good, reroute that hose. I've heard the pulses from the vent can upset the airflow dynamics within the airbox, too-on top of everything else folks have mentioned. Don't know if that's true, but certainly oil will start to backup into the airbox!

My solution for off-road is to use a T- adapter to route the hose both up and the stock position. Had a "parts bin" adpater an old ATC200. the new hose goes between the right side radiator and frame, then up next to the CDI. I put a little 90 degree bend turndown tip on it to help from water splash at the top.

Place it at the point where the vent hose is starting to point downward. This way the excess oil will still come out and vent properly. But for the dreaded "starting in water" routine I still have the open top end to breath to get me out of the water w/o sucking in a bunch of muck!!

For motard, are you just worried about contaminating the track or getting it on your boots/bike? Maybe a solution for you is to use a catchtank of sorts? If you route the hose only up, my bet is you'll hear some gurgling and slurping noises that may drive you a little nuts. maybe not, though!

  • MX_Tuner

Posted October 15, 2001 - 03:27 PM

#13

Bluethunder, I agree for the most part. I don't quite see it as screwing myself over, though. My point was the temp of the air isn't an issue if it is compensated for with the mixture adjsutments.

My wr was one of, if not *the* first '98 WR's to hit the Atlanta area way back when. We were experimenting with different routing locations. I had heard the Euro models had this hose routed to the blank fitting at the top of the air boot between the carb and air filter. I ran mine to this location more for waterproofing than anything else. I've looked in the air boot and always have a substantial amount of oil in the boot. I have *never* had any running problems with this set up, with the stock 400 motor or with the 450 motor. It isn't my first choice for a location but it has served its purpose perfectly with no adverse effects. Call it trying to learn via trial and error. At worst I'd have had to plug the hole I drilled into the fitting in the air boot. But I've had no reason to switch.

I've seen some hoses routed into the top of the air box. These usually have an air filter that is saturated with engine oil vapor.

I like Mcarp's idea of installing a "tee" fitting and running one hose high and one in the stock location. If I didn't have the set up I do, I'd try that with a filter on each end. Uni makes a great little mini K&N style breather for about $13 that fits perfectly in the stock hose.

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MX Tuner

  • TeamScream

Posted October 15, 2001 - 08:28 PM

#14

Yeah the main reason I dont want to leave the hose in its current location is the obvious desire NOT to oil my rear tire down at speed whilst I use tactical surgical precision and hit the same line on the track everytime (fantasy is good right?) but seriously, its a oil on the track issue more than anything.....
Thanks

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01' WR426,YZ timing,EMP #2,#48Pilot,#100PAJ,#175 Main,BK mod,Kouba T-Handle,YZ pipe, open airbox,Gray-Wire Pulled,K&N Filter, throttle stop mod,CA Street Legal,Pure SuperMotard 17 in. wheels,Braking 320mm "wavy" front rotor, 15/46 gears,ProTaper bars,




 
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