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techtalk:ref:engmech05 [2019/07/26 17:34]
hippysmack [Vent Outlet Above vs Below the Head Vents]
techtalk:ref:engmech05 [2020/03/01 23:27]
hippysmack [Filter on End of the Vent Line]
Line 112: Line 112:
 To stop a leak, you may be tempted to tighten the bolts even more. \\ To stop a leak, you may be tempted to tighten the bolts even more. \\
 This could result in breaking the bolt. \\ This could result in breaking the bolt. \\
 +
 +On 04-up heads, changing to aftermarket breather bolts means using bolts with the bigger I.D. (91-03) style bolts. \\
 +The results of using the bigger holed bolt would be a slower rate of outflow and less positive crankcase pressure on a stock motor. ((Hippysmack of the XLFORUM http://​xlforum.net/​forums/​showthread.php?​t=2073932&​page=4)) \\
 +But the timing of the upstroke is the same which then pulls a vacuum. \\
 +The umbrella valve will close down only when inside air pressure is lower than outside air pressure. \\
 +If the inside pressure can't get out fast enough before piston upstroke happens the umbrella may '​float'​ or not close all the way. \\
 +If the umbrella floats, X amount of extra air is pulled in until it does close. \\
 +(on top of what didn't get completely out on the last downstroke = more air in the engine on the next downstoke = oil puking out the breather). \\
 +How much slower the bigger bolt hole yields will vary with different engines. \\
 +
 +However, the smaller holed bolts were designed to OEM specs internally. \\
 +If you've upgraded to bigger pistons, there will be more positive pressure displaced out the breathers on downstroke. \\
 +This may negate the need for higher pressure generated by the smaller holed bolts. \\
 +This may be something you'd want to watch since there isn't sufficient data to prove one way or the other. \\
  
 {{:​techtalk:​ref:​engmech:​breather_mod_2_by_hagen.jpg?​direct&​300|}} ((photo by Hagen of the XLFORUM http://​xlforum.net/​forums/​showthread.php?​t=146084&​page=11)) {{:​techtalk:​ref:​engmech:​ds_breather_bolt_by_hagen.png?​direct&​300|}} ((photo by Hagen of theXLFORIM http://​xlforum.net/​forums/​showthread.php?​t=692845)) {{:​techtalk:​ref:​engmech:​broken_banjo_bolt_by_scout99.jpg?​direct&​200|}} ((photo by Scout99 of the XLFORUM http://​xlforum.net/​forums/​showthread.php?​t=28299)) {{:​techtalk:​ref:​engmech:​breather_mod_2_by_hagen.jpg?​direct&​300|}} ((photo by Hagen of the XLFORUM http://​xlforum.net/​forums/​showthread.php?​t=146084&​page=11)) {{:​techtalk:​ref:​engmech:​ds_breather_bolt_by_hagen.png?​direct&​300|}} ((photo by Hagen of theXLFORIM http://​xlforum.net/​forums/​showthread.php?​t=692845)) {{:​techtalk:​ref:​engmech:​broken_banjo_bolt_by_scout99.jpg?​direct&​200|}} ((photo by Scout99 of the XLFORUM http://​xlforum.net/​forums/​showthread.php?​t=28299))
Line 120: Line 134:
 The filter adds resistance to the vent pressure coming out of the engine. \\ The filter adds resistance to the vent pressure coming out of the engine. \\
 This resistance can add to goop in the line / filter later. \\ This resistance can add to goop in the line / filter later. \\
 +It can also increase the vacuum inside the engine, which on a street bike, translates to weeping gaskets. \\
  
 The filter does not keep debris from coming back into the engine. ((Folkie of the XLFORUM http://​xlforum.net/​forums/​showthread.php?​p=2087347)) \\ The filter does not keep debris from coming back into the engine. ((Folkie of the XLFORUM http://​xlforum.net/​forums/​showthread.php?​p=2087347)) \\
Line 149: Line 164:
 ====== Pics of Aftermarket Breather Valves ====== ====== Pics of Aftermarket Breather Valves ======
  
-|Doherty Power Vents with the line routed up then \\ down and attached to the bottom of the frame. ((photo by RIORoosen of the XLFORUM http://​xlforum.net/​forums/​showthread.php?​t=146084&​page=18))|Hayden KVP38 breather valve, used with the \\ [[techtalk:​ref:​engmech05d|Deimus Mod]] (cam chest breather conversion). ((photo by 60Gunner of the XLFORUM http://​xlforum.net/​forums/​showthread.php?​p=5763918#​post5763918))| +|Doherty Power Vents with the line routed up then \\ down and attached to the bottom of the frame. ((photo by RIORoosen of the XLFORUM http://​xlforum.net/​forums/​showthread.php?​t=146084&​page=18))
-|{{:​techtalk:​ref:​engmech:​breather_mod_by_rioroosen.jpg?​direct&​300|}}|{{:​techtalk:​ref:​engmech:​deimus_mod_8_by_60gunner.jpg?​direct&​300|}}|+|{{:​techtalk:​ref:​engmech:​breather_mod_by_rioroosen.jpg?​direct&​300|}}| 
 + 
 +|Hayden KVP38 breather valve, used with the \\ [[techtalk:​ref:​engmech05d|Deimus Mod]] (cam chest breather conversion). ((photo by 60Gunner of the XLFORUM http://​xlforum.net/​forums/​showthread.php?​p=5763918#​post5763918))|  Hayden breather opened up. ((photos by leucadiaGuit of the XLFORUM http://​xlforum.net/​forums/​showthread.php?​t=2004869 cropped by Hippysmack)) ​ |
 +|{{:​techtalk:​ref:​engmech:​deimus_mod_8_by_60gunner.jpg?​direct&​300|}}|{{:​techtalk:​ref:​engmech:​hayden_krankvent_3_by_leucadiaguit_-_cropped.jpg?​direct&​300|}}|{{:​techtalk:​ref:​engmech:​hayden_krankvent_2_by_leucadiaguit_-_cropped.jpg?​direct&​300|}}|