The Sportster and Buell Motorcycle Forum DK Customs  

Go Back   The Sportster and Buell Motorcycle Forum > SPORTSTER MOTORCYCLE ZONE > Sportster Motorcycle Era Specific and Model Specific > Ironhead Sportster Motorcycle Talk (1957-1985)
XLF Gallery XLF Classifieds XLF Blogs XLF Shout XLF Arcade XLF Disclaimer/Privacy Statement/Terms Of Use

Ironhead Sportster Motorcycle Talk (1957-1985) For all those that wanna talk about Ironhead Sportster Motorcycles

Members Birthdays
qrtsteve (60), johnboy (45), bmonty72 (42), superscythe (41), grahamc (29)
Fix My Hog
Biltwell
Licks Cycles
Fix My Hog

Foxcreek Leather
Reply
 
Share Thread Tools Display Modes
  #21  
Old 18th August 2009
bustert's Avatar
bustert bustert is offline
Senior Custom Bike Builder
 
Join Date: Jul 2008
Posts: 2,545
Sportster/Buell Model: 1200s
Sportster/Buell Year: 2001
Sportster/Buell Model #2: xlch
Sportster/Buell Year #2: 1974
Reputation: 15822
bustert is a glorious beacon of lightbustert is a glorious beacon of lightbustert is a glorious beacon of lightbustert is a glorious beacon of lightbustert is a glorious beacon of lightbustert is a glorious beacon of lightbustert is a glorious beacon of lightbustert is a glorious beacon of lightbustert is a glorious beacon of lightbustert is a glorious beacon of lightbustert is a glorious beacon of light
Default

as i brought out in another post about removing this valve, it is not a culprit in getting engine oil to the primary side. you have to remedy the problem at the oil pump. this valve largely seals by dynamic action aka windage from the down stoke of the pistons. the disk and spring are only a marginal seal at static, and yes it will leak. an engine will produce more hp if there is a slight vacumn in the c/c as it does not have to over come pressure, however, excess vacumn can cause problems in scavenging the oil from the c/c. this valve lets a controlled amount of air into the c/c (remember that the c/c vapor and oil was sent through the timed breather vave on the downstroke) along with any oil that has gotten over the disk level. the flow is not from c/c to primary. there is no advantage of removing it. the transmission on the models that use it are designed for engine oil. blocking it and going with gear oil can cause problems down the road if your c/c fills up with oil. you can always tell when the c/c has excess oil as the rear cylinder will usually smoke until the oil is scavenged out. you can also notice a reluctance in the engine wanting to run up as it is carring all of that exceess oil around draining off hp. why hd used it is a mystry to me but i guess the engineer was doing the best he could. the excess oil in the primary will be scavenged back to the engine through this valve. this debate will probable go on and so be it. to each his own. btw: on race engines, it is imperitive to not allow oil to hit the crank and that is why windage trays and baffled oil pans are used. not only can it rob hp but it can also cause crank deflection and failure.
Reply With Quote
  #22  
Old 18th August 2009
FourCams's Avatar
FourCams FourCams is offline
Senior Chief Master Mechanic 1st Class
 
Join Date: Dec 2008
Location: Seattle
Posts: 1,295
Sportster/Buell Model: XLCH
Sportster/Buell Year: 1969
Sportster/Buell Model #2: XLCH
Sportster/Buell Year #2: 1972
Other Motorcycle Model: FXSTC
Other Motorcycle Year: 1996
Reputation: 5013
FourCams is just really niceFourCams is just really niceFourCams is just really niceFourCams is just really niceFourCams is just really niceFourCams is just really niceFourCams is just really niceFourCams is just really niceFourCams is just really niceFourCams is just really niceFourCams is just really nice
Default

Rep coming your way Bustert. That explaination makes sense.
__________________
♠ 1969 XLCH ♠ 1972 XLCH ♠ 1996 FXSTC ♠
Reply With Quote
  #23  
Old 18th August 2009
IronMick's Avatar
IronMick IronMick is offline
Rider Of The Iron Steed
 
Join Date: Dec 2003
Location: London, ON Canada
Posts: 26,940
Sportster/Buell Model: XLH
Sportster/Buell Year: 1978
Reputation: 116664
IronMick has much to be proud ofIronMick has much to be proud ofIronMick has much to be proud ofIronMick has much to be proud ofIronMick has much to be proud ofIronMick has much to be proud ofIronMick has much to be proud ofIronMick has much to be proud ofIronMick has much to be proud ofIronMick has much to be proud ofIronMick has much to be proud of
Default

Quote:
Originally Posted by IronMick View Post
OK, does the FM and OEM parts book refer to it as a transfer valve? or a breather valve? I am interested because it seems to me that transfering oil is not its main function, but that acting as a breather is main, and that oil transfer is an unwanted side effect??
Quote:
Originally Posted by 72Iron View Post
Part # 25075-55 Oil Transfer Valve from my OEM parts book.
Darn! I was hoping for different. Oh well, OTV is be.
Reply With Quote
  #24  
Old 18th August 2009
IronMick's Avatar
IronMick IronMick is offline
Rider Of The Iron Steed
 
Join Date: Dec 2003
Location: London, ON Canada
Posts: 26,940
Sportster/Buell Model: XLH
Sportster/Buell Year: 1978
Reputation: 116664
IronMick has much to be proud ofIronMick has much to be proud ofIronMick has much to be proud ofIronMick has much to be proud ofIronMick has much to be proud ofIronMick has much to be proud ofIronMick has much to be proud ofIronMick has much to be proud ofIronMick has much to be proud ofIronMick has much to be proud ofIronMick has much to be proud of
Default

Quote:
Originally Posted by RRB View Post
... But I think that Mick and MDT are right about the nomenclature being wrong.

Perhaps the whole thing is an embarrassment to HD and that is why they seldom reference it or reference it improperly ...
So, a Vent from the primary to the crankcase that we will refer to as an Oil Transfer Valve.
Reply With Quote
  #25  
Old 18th August 2009
RRB RRB is offline
Senior Chief Know It All
 
Join Date: Jul 2006
Posts: 898
Sportster/Buell Model: XLH
Sportster/Buell Year: 1966
Reputation: 441
RRB is on a distinguished roadRRB is on a distinguished roadRRB is on a distinguished roadRRB is on a distinguished roadRRB is on a distinguished road
Default

Quote:
Originally Posted by IronMick View Post
So, a Vent from the primary to the crankcase that we will refer to as an Oil Transfer Valve.
Yeah, I guess, Mick. But I think, as you and MDT and some others do, that it is less about oil and more about crankcase pressure. It seems to be a bit of a conundrum. According to conventional wisdom, it seems to be an "Oil Transfer Valve" only when it is transferring the oil in the wrong direction.

Perhaps this would be a good question to ask HD, if there is anyone there these days that could give an informed answer, or would care to do so.
Reply With Quote
Know Thy Hog

Reply

Bookmarks


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


Custom Search

All times are GMT +1. The time now is 16:17.


Powered by vBulletin® Version 3.8.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
XL Forum - Linson Media LLC