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Reed valve crank case breather (Heiden Tuning)
- Thread starter Leslie
- Start date
Charles13
XS650 Addict
They work, it keeps the engine from pressurizing and starting oil leaks, it’s also easier on your rings so it’s not just bling.
Charles13
XS650 Addict
Some mount the catch can up high so that they can drain the oil back to the crankcase after it settles out of the mist.
I just run this one from them. Same thing but cheaper. Just mount it near the rear engine mount. I have two on the XS2 and get very little oil mist.
https://www.heidentuning.com/xs650-...kcase-ventilation-valve-reed-type-detail.html
https://www.heidentuning.com/xs650-...kcase-ventilation-valve-reed-type-detail.html
That would defeat the purpose of the catch can. The oil has blowby debris mixed with it. Only the air exiting the top after passing the baffles is clean.
Its been a long time
Doesn't know nothing.
Agreed. Really don't want what is mostly emulsion/water with some oil draining back into the engine.
One option is to route the tube down through the rear engine mount plate hole towards and above the chain.
Although I’ve not noticed a visible drip.
Once again, you're routing dirty oil to lubricate the chain.
Charles13
XS650 Addict
Im not sure that all the NASCAR crew chiefs (who all run dry dumps with basically this setup) would agree. All engine oil has blow by debris mixed with it but the reed valve makes the rings seal better and therefore has less blow by debris than a motor without one, and all that oil stays in the motor and is recycled.
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Charles13
XS650 Addict
Where exactly is the oil picking up water to create an emulsion? Especially mostly water? Even on the most humid day the hot catch wouldn’t reach the required dew point to condensate water vapor out of the air. Please explain I’m not sure I understand.
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Well, you said it,, all engine oil has blowby debris mixed in it.
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AUTOMAN
XS650 Addict
It does not help seal the rings.
Water is from combustion products.
Blow-by debris? as in solids?
Water is from combustion products.
Blow-by debris? as in solids?
Crankcase blowby gasses contain soot, unburnt fuel, exhaust gas particulates, carbon, water, acid. Plus probably a heap of other particulates. Ideal stuff to lube your chain with. Air, the stuff drawn in through the carbs, is made up of Nitrogen, oxygen and argon, it also contains up to 4 percent water vapour, depending on location.
Charles13
XS650 Addict
>4% water vapour at a 14:1 ratio is about .07% which 99% goes out the exhaust valve, this will not cause the oil to emulsify, and certainly is not a concern when recycling the oil for 1000 miles. If your oil is a milky emulsion when you drain it you have been riding through a swamp!
By returning oil from a catch can to the crankcase you are not doing anything different that the engine does anyway. Depending on how much oil you can capture from your crankcase vent it may keep the oil level from prematurely running low.
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Charles13
XS650 Addict
Charles13
XS650 Addict
I’m just an idiot that has some mechanical aptitude and common sense (it often trumps arguing), it’s something that is lacking in today’s society unfortunately.
https://www.xs650.com/threads/crankcase-vent-using-a-reed-valve.61188/
@toglhot
How does the crankcase vapor know to separate out the water and "combustion byproducts' and send them to the crankcase vent?
@toglhot
How does the crankcase vapor know to separate out the water and "combustion byproducts' and send them to the crankcase vent?
Charles13
XS650 Addict
In a picture from the link you provided; after 9 months the accumulation looks perfectly normal, no solid by products, no water. This was an open bottle with a hose going in the top (common on road race bikes), vapor goes up by the hose, out to the atmosphere and oil drips out the hose to the bottom. In big bore turbocharged drag bikes they have multiple vents going to a aluminum can with various baffles (mostly plates with chamfered holes to separate the air from the oil), and another baffled hose outlet (out the top) going to a filter for the air to escape then, the de-aerated oil drains back into the cases usually through a fitting attached to the oil fill hole, they have never had a problem with water as far as I know.
I would attach a pic but for some reason the button is greyed out.
