Hayden crankcase relief valve
Dirt don't hurt
Joined: Jan 2011
Posts: 21,065
Likes: 4,561
From: Haslet Texas
You might want to read that again.
It simply reduces crankcase pressure not increase crankcase vacuum.
http://www.jpcycles.com/product/740-589
It simply reduces crankcase pressure not increase crankcase vacuum.
http://www.jpcycles.com/product/740-589
Road Master
Joined: Oct 2011
Posts: 957
Likes: 2
From: Carlsbad Springs Ontario
As George Carlin said ... its all bullshit , and its bad for ya .
From what i see , the famous plastic rotary vent valve does all the crankcase breathing at the appropriate times and the effluent is routed to the air filter assy. to be reburned as per. all the engines built in the last 30 years.
I must admit that this apperrantly useless , grosselley overpriced standard PCV unit from Hayden is a complete ripoff and i for one am very dissapointed to see this **** from them .
From what i see , the famous plastic rotary vent valve does all the crankcase breathing at the appropriate times and the effluent is routed to the air filter assy. to be reburned as per. all the engines built in the last 30 years.
I must admit that this apperrantly useless , grosselley overpriced standard PCV unit from Hayden is a complete ripoff and i for one am very dissapointed to see this **** from them .
Elite HDF Member
Joined: Sep 2007
Posts: 4,468
Likes: 12
From: Bluffton, South Carolina
We've used them on most of the engines we've built. It is actually a little more than "just a pcv valve. The harley v-twin engine has an "unbalanced pressure signal" which is much more severe than any automotive engine. This is caused by the simple fact that in most automotive engines you hav a piston coming down causing increased pressure, but it is balanced by another piston going up at the same time. That is why when you take the oil filler cap off you don't have the pressure pulses that a v-twin has. The pressure pulses in a v-twin make short work of a pcv valve, and most can't open/close fast enough to make any real difference. Hayden put a lot of research into this. If you are running Total Seal rings they suggest that you use tis product as it helps with ring seal in the v-twin engines. Now Total seal doesn't own hayden so they gain nothing by reccomending it other than a more satisfied customer. Hope this helps.
John
John
Seasoned HDF Member
Joined: Nov 2009
Posts: 15,705
Likes: 22,718
From: Farmington ,MS
Seasoned HDF Member
Joined: Aug 2008
Posts: 5,078
Likes: 2,150
From: Ohio
I can see this miracle repair good for not allowing atmosphere moisture from entering the crankcase during breathing opration but other than that a brilliant marketing srategy targeting the HD owners unsure of the OEM breathing design when a spot of oil shows up somewhere by discharge, I'm with my Evo brothers on this one.
Seasoned HDF Member
Joined: Aug 2008
Posts: 5,078
Likes: 2,150
From: Ohio
John, lets talk about this. Evo equalizes crankcase pressure through a window of timed rotating breather, how can this device alter the timed open process externally? If it has too much exiting external pressure you have a mechanical problem, if it is normal pressure you don't have a problem. The product is advertising reducing crankcase pressure and can't see how it alters a mechanical designed window of opening.
Reading into your theory, I think you are heading towards equalized pressure is best for ring seal which this product can provide as a S&S reed valve does but advertised as reducing crankcase pressure which if you have a sound engine, this shouldn't be an issue. If I'm wrong on assuming your intentions, please let me know. If your theory is relieving pulses and crankcase pressure then I'm still confused by over riding the mechanical timed breather. Debate my friend present not arguement, see Evo forum rules!
Learning process is by not walking away or making mistakes, I've done both
Reading into your theory, I think you are heading towards equalized pressure is best for ring seal which this product can provide as a S&S reed valve does but advertised as reducing crankcase pressure which if you have a sound engine, this shouldn't be an issue. If I'm wrong on assuming your intentions, please let me know. If your theory is relieving pulses and crankcase pressure then I'm still confused by over riding the mechanical timed breather. Debate my friend present not arguement, see Evo forum rules!
Learning process is by not walking away or making mistakes, I've done both
Last edited by 1997bagger; Feb 24, 2013 at 02:14 PM. Reason: 3rd grade education
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Elite HDF Member
Joined: Sep 2007
Posts: 4,468
Likes: 12
From: Bluffton, South Carolina
!997,
Have you ever pulled the timing plug and started the engine or put your finger over the vent hose on a "bottom breather"?? As previously stated on most multi cylinder engines you have a piston going up each time a piston goes down. The bottom of the pistons move as much air as the tops. If you have enough blow-by to exacerbate the problem, then yes no the valve in the world would help. Yes it does work in a similar fashon as the S & S reed valve which we have also used with success.
The Hayden doesn't over ride the stock rotary timed breather, it helps it. The early rotary breathers were woefully innsuficient. Later breathers were improved, but if you modified the engine, or ran it at higher RPM's even it couldn't keep up. The S & S steel rotary valve was even better, but you still had room for improvement by widening and timing the opening in the block. This required a good die grinder, long shank aluminum bit, degree wheel, patience, and a lot of work. When you were done you still had an engine that was under ventilated!!! Take a good look at any V-twin drag engine and you will see a plethera of vents and drain lines. Now take this same platform and increase the displacement and you just compound the problem. Hope this helps.
John
Have you ever pulled the timing plug and started the engine or put your finger over the vent hose on a "bottom breather"?? As previously stated on most multi cylinder engines you have a piston going up each time a piston goes down. The bottom of the pistons move as much air as the tops. If you have enough blow-by to exacerbate the problem, then yes no the valve in the world would help. Yes it does work in a similar fashon as the S & S reed valve which we have also used with success.
The Hayden doesn't over ride the stock rotary timed breather, it helps it. The early rotary breathers were woefully innsuficient. Later breathers were improved, but if you modified the engine, or ran it at higher RPM's even it couldn't keep up. The S & S steel rotary valve was even better, but you still had room for improvement by widening and timing the opening in the block. This required a good die grinder, long shank aluminum bit, degree wheel, patience, and a lot of work. When you were done you still had an engine that was under ventilated!!! Take a good look at any V-twin drag engine and you will see a plethera of vents and drain lines. Now take this same platform and increase the displacement and you just compound the problem. Hope this helps.
John
Last edited by miacycles; Feb 25, 2013 at 09:34 AM.
Road Master
Joined: Oct 2011
Posts: 957
Likes: 2
From: Carlsbad Springs Ontario
pcv.
I challenge any Haydon rep. out there to qualify the outragous price for this item with some sound technical info. Good Luck there !