I just fit a new pair of Amals to my 850, I bought a new R-0990 K&N filter to use. I have an old one that has a tube in it to attach the hose from the oil tank that usually goes to the stock filler plate. I was going to just do that but I am wondering if this is the best option. Or is there a better idea?? Thanks, Glenn T.S.
K&N filter and oil tank vent hose...
- Thread starter gtsun
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I don't know why anyone would leave the oil tank vent connected to the air filter.
I ran a new line straight down from the oil tank and just discreetly let it hang out in the breeze. If you don't overfill the tank you shouldn't get much if any oil coming out.
I ran a new line straight down from the oil tank and just discreetly let it hang out in the breeze. If you don't overfill the tank you shouldn't get much if any oil coming out.
I like the little cat bite all the best, basically don't like seeing the line run back to the tail and don't want it just going down in front of the rear tire. Nothing but minor vapor has ever come out of mine in the past but just in case you know. Don't like it going into the air filter either so a little catch bottle will be fine for now thanks.
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It's a smog device, of course, and allows crankcase/oil tank vapors to be burnt by the engine.
Back in the early '70's my dad bought a '56 Chevy pickup; California required a "positive crankcase ventilation device" as a precondition to transfer of title/registration. He had me go out and buy/install a plate that went under the carb which had a hose barb on it that connected to the valve cover vent. That was before federal smog regs.
Back in the early '70's my dad bought a '56 Chevy pickup; California required a "positive crankcase ventilation device" as a precondition to transfer of title/registration. He had me go out and buy/install a plate that went under the carb which had a hose barb on it that connected to the valve cover vent. That was before federal smog regs.
htown16
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Also using a K&N air filter. Drilled a hole through the plate and mounted a Drag Specialties breather filter below the air filter. The breather line off the top of the tank comes in from the back. Also used the bottom of the plate to mount the Mikes XS reed valve on the breather line from engine.
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htown16 said:Also using a K&N air filter. Drilled a hole through the plate and mounted a Drag Specialties breather filter below the air filter. The breather line off the top of the tank comes in from the back. Also used the bottom of the plate to mount the Mikes XS reed valve on the breather line from engine.
I have individual pods, so I just laid the pod connected to the breather hose on top of and between the carb pods. Haven't seen any oil, and I assume any fumes get sucked into the intakes with incoming air.
I changed the hose since this pic so the breather pod lays parallel with the air filters.
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gtsun said:
I just have a 3 inch hose coming off the tank with a tiny K&N mounted to the end. The K&N sits right under the rear of the fuel tank. Works fine. Jim
PS.
I do have a little tee in the center of the 3 inch hose with a tiny tube that goes down to the swingarm. I get just enough oil down that hose to keep the swingarm bushings lubed. Over 100,000 miles on the bushings now and no detectable play. Jim
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Biscuit said:
If you don't use a catch tank or have a secondary use (like lubing swingarm bushings or the drive chain) and the hose and small filter is higher than the oil level in the tank, it just keeps things clean without restricting the oil tank from breathing.
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Any oil in the combustion process will increase the propensity to detonate/pink, so that's something to keep in mind if you're having knocking problems.illf8ed said:
As backsideslider noted, it's a smog thing. I run mine into the air filter if only to let the engine consume any oil vapors that might make their way out. Keep in mind that anything that pushes past the piston rings (unburned fuel) also finds its way out through this tube, so I can rest easier knowing my nasty, unburned hydrocarbon spew is now nasty, burned hydrocarbon spew. Yeah, that makes it all-l-l-l better...
Nathan
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I use the standard MKIII oil separator except I replaced the fitting on the bottom with a hose barb. Then I ran a hose down below the frame with a vent a got off of a Jeep differential. My thinking is the fumes get caught in the air box and any moisture and oil will run down the hose. After over 1,000 miles I have no oil in my air box and nothing dripping out of the hose.
I am sure something like this can be adapted to almost any air filter
I am sure something like this can be adapted to almost any air filter
My bike is 1970 roadster. I ran my engine breather through a MikesXS reed valve into a catch tank and thence to a small K&N pod, bypassing the oil tank. Don't see how any good can come from directing contaminants to the oil tank.
That allowed me to use the port at the top of the tank for tank breathing via a tube along the seat rail, and so to blank off the inbuilt pipe in the central oil tank that drips condensed oil vapour into the air filter.
I had planned to be a good boy and route the engine gases into the front of of the air filter, but it was easier to fit a K&N and not despoil my filter plate.
That allowed me to use the port at the top of the tank for tank breathing via a tube along the seat rail, and so to blank off the inbuilt pipe in the central oil tank that drips condensed oil vapour into the air filter.
I had planned to be a good boy and route the engine gases into the front of of the air filter, but it was easier to fit a K&N and not despoil my filter plate.
Danno said:
Oh OK, so the filter is not really intended to filter anything, it's just there as kind of a sponge. My MK3 has long ago lost it's airbox and the accompanying tank breather plumbing. I'm still running only the original hose from the timing case to the tank, no special reed valves or anything else, and from the tank just a hose running down and secured to the right frame rail. On a coolish damp day there might be a dime sized oil/condensation drip on the garage floor in the morning.
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