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This is just a one way automotive brake booster vent. (Check valve) Most just vent right onto an air filter..
I found mine at O'Reillys Auto parts. Tho they couldn't find it in their system.. I spotted it on their hooks lol
Its just a Ford etc.. style old brake booster check valve
Where might I ask you purchased those filters? Great set up!Dual outlet breather box converted to a single. thin walled crankcase vent hose from MikesXS with two light external springs and a billet filter mounted to the crankcase. Easy to remove the foam from the filter and wash at service times. Hasn't left a spot of oil on the ground in over 3000klm.
Interested in your comment that pod filters will cause carb tuning issues. Can you please elaborate? Thanks.That's hard to say. I would think the hole in the rubber plug should be a little bigger because you're down to one pipe now, but maybe not as big as it would be by removing the plug. Maybe someone with a later factory single pipe breather could check the hole size on that for you?
Normally, your breather breaths in and out as the pistons move up and down. The check valve is a one way valve that lets pressure out but not back in. That creates a small vacuum in the crankcase and that's supposed to be beneficial for a couple reasons. First, the engine is supposed to make a bit more power like that. Second, that slight negative pressure can help prevent oil leaks and possibly alleviate minor ones you may already have.
Many of us who run pods use a short length of hose and locate the check valve above the pod filter. If any oil or oil mist does come out, it will just get recycled through the engine. This sort of mimics the factory set-up of having the breather hoses fed into the airbox. I had no clearance issues setting this up and in fact, it uses less hose and takes up less space than the factory set-up. This was my original set-up when I still had K&N pods .....
I have since switched to UNI foam pods because the K&Ns don't work well with our CV carbs. The check valve set-up remains the same. I notice you have the K&N pleated type pods. They will cause you carb tuning difficulties.
Thx. I’m running 32mm PWK carbs. At the filter end they are 54 mm or close to 2-1/8”. Had a look at Uni’s website an it looks like the diameter jumps from 2” to 2-1/4”. Does the urethane flange have enough “give” to stretch the 2” over my 2-1/8” carbs?Pleated K&N type pod filters are the troublesome ones. The pleats disrupt the air flow, make it turbulent, and that messes with the slide lift on these CV carbs. Best pods to use on these are the straight foam UNI pods.
great thxThe PWK are a regular slide carb so you could use the K&N type filter on them. But yes, if going with a UNI, the 2 1/4" will tighten down just fine to 2 1/8". The 2" version would be a stretch and very tight. I don't recommend it.
Dears,
Currently I am sandblasting the two airfilter housings. I noticed both breather connections are cut of and the remaining parts into the housings are closed.
As my bike will be the subject of an official check, to get a licence plate again, I intend to make some kind of engine breating system, returning the fumes into the engine.
After reading all articles on this subject on this forum, I got some ideas to reinstall an improved engine breathing system. Still some doubts however.
Basically the volume of both cilinders comes out of the breather each rotation. Still only one cilinder sucks in air during that rotation. This means the vapor will be pressed into the other air filters, flowing to the other air filter from which the engine sucks fresh air that moment. I expect this will pollute the filters with oil. Can hou agree?
I do not understand the use of pcv valves on this twin; to my opinion the vacuum during the upgoing stroke, will influence the piston velocity and thus the power, though very slightly naturally.
Recently I worked on a Honda VT600 of a relative (you would not want to own one); this V-engine has a breather hose coming from each cilinder, leading to a small reservoir. This reservoir has a tube connected to the air filter box, and has a plugged drain hose which need to be drained every now and then.I think this is a nice solution as the reservoir collects oil (when there is any) and acts as a buffer volume for the fumes. Please give me your thoughts.
Bert