Differences

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--- techtalk:ih:engmech04a [2019/06/14 01:42]
hippysmack [Cut Down]
+++ techtalk:ih:engmech04a [2019/06/14 19:23]
hippysmack [Pros and Cons of Functionality]
@@ Line 2: / Line 2: @@
 ====== IH: Engine Mechanicals - Sub-04A ======
 ====== Splitting Rocker Boxes ======
+When you cut the boxes there will be an oil passage that will need to be plugged (between the now two sides). ((hoosier xlc of the XLFORUM http://xlforum.net/forums/showthread.php?t=120623&page=2)) \\
+You will have to drill and tap another entrance port for the oil line (between them). \\
 Removing the boxes and head together is far less frustrating. ((JonesL of the XLFORUM http://xlforum.net/forums/showthread.php?t=1719533&highlight=splitting+rocker+box&page=5)) \\
 Otherwise you've just invented a new 'chinese puzzle'. \\
@@ Line 9: / Line 12: @@
 **Pros**: \\
+There really is nothing to be gained by splitting the Rocker Boxes, it's purely Cosmetic. ((hoosier xlc of the XLFORUM http://xlforum.net/forums/showthread.php?t=130964&page=3)) \\
+It's just a matter of personal preference. But then again so is half the stuff folks do to their bikes. \\
+There is nothing different in splitting the rocker boxes than; \\
+Trimming the cam cover, drilling holes in the chain/belt guard, welding a hardtail section on a swing arm frame, \\
+Running the wires internally in the bars, a slick paint job, flat blacking everything, chroming everything, \\
+Installing 16"+ apes on HD's Sport Bike, adding a 250mm rear tire or side mounting a license plate. \\
+Some split the rocker boxes for adding dual plugged heads. The right side sparkplug is on the same angle as the left. ((fdny37 of the XLFORUM http://xlforum.net/forums/showthread.php?t=130964&page=3)) \\
+On some other dual plug bikes, the right side plug was installed more towards the top of the head and the boxes didn't require splitting. \\
+Cometic metal rocker gaskets seem to help with leaks. \\
 If the rocker covers are doing a "hula dance" when in one full piece; ((Tim The Grim of the XLFORUM http://xlforum.net/forums/showthread.php?t=1719533&highlight=splitting+rocker+box&page=5)) \\
 Once they are split, each half is no longer reacting to the flex caused by the opposing side and is therefore more stable. \\
+A lot of guys have proven that the middle bolt contributes very little (if anything) to the stock configuration. ((Ferrous Head of the XLFORUM http://xlforum.net/forums/showthread.php?t=1998127&highlight=split+rocker+box&page=3)) \\
+That would make the process of doing the plumbing between the two halves a little easier. \\
 **Cons**: \\
@@ Line 27: / Line 44: @@
 Your pushrods are doing the same thing 29 times a second at 3500 rpm. \\
 The last thing we want is to make things less rigid. \\
+The pushrods have enough trouble with harmonics without adding another place for the valve train to flex. ((mrmom9r of the XLFORUM http://xlforum.net/forums/showthread.php?t=1682099&highlight=splitting+rocker+box)) \\
+I've seen flex as high as .025" just rolling an engine with big valve springs over on the bench. \\
+If we lose up to .025" or more due to box flex, that is that much less that the valve is opening. ((Monte03 of the XLFORUM http://xlforum.net/forums/showthread.php?t=1682099&highlight=splitting+rocker+box&page=2)) \\
+So much for your hi lift cam. \\
 Even on dead stock valve train the naked eye can actually see the pushrod end of split boxes flex when pushing the kicker thru. ((DR DICK of the XLFORUM http://xlforum.net/forums/showthread.php?t=1719533&highlight=splitting+rocker+box&page=2)) \\
@@ Line 44: / Line 66: @@
 (or optionally replace it with a hard shim) \\
 Box flex is real and it doesn't have to be. \\
+You can put your hand on boxes that have been split and you will feel them moving around. ((fdny37 of the XLFORUM http://xlforum.net/forums/showthread.php?t=120623&page=2)) \\
+The only gaskets that help are the metal ones from Cometic. All the rest of the paper ones actually just get squeezed out. \\
+Strong valve springs add to the moving around. \\
 When using dual plug heads; ((DR DICK of the XLFORUM http://xlforum.net/forums/showthread.php?t=1719533&highlight=splitting+rocker+box&page=2)) \\
@@ Line 51: / Line 77: @@
 So they move the plug farther down as a better option. \\
-===== Cut Down =====
+To keep the strength of the center bolt design, you can weld up the oiling cross hole and run external lines from the outside. ((ryder rick of the XLFORUM http://xlforum.net/forums/showthread.php?t=1998127&highlight=split+rocker+box&page=2)) \\
+That is better than splitting the boxes. \\
+To dual plug the heads, the plug electrode location is what is critical, not the angle the plug screws in from. ((ryder rick of the XLFORUM http://xlforum.net/forums/showthread.php?t=1682099&highlight=splitting+rocker+box)) \\
+You can use a small spark plug 12mm or even 10mm. A big plug doesn't make any bigger spark. \\
+{{:techtalk:ih:engmech:dual_plugging_ihs_1_by_ryder_rick.jpg?direct&300|}} ((photo by ryder rick of the XLFORUM http://xlforum.net/forums/showthread.php?t=1682099&highlight=splitting+rocker+box)) \\{{:techtalk:ih:engmech:dual_plugging_ihs_2_by_ryder_rick.jpg?direct&300|}} ((photo by ryder rick of the XLFORUM http://xlforum.net/forums/showthread.php?t=1682099&highlight=splitting+rocker+box)) \\
+====== General Process Of Splitting the Rocker Box ======
+These are Shovelhead rocker boxes but the process is about the same. ((hoosier xlc of the XLFORUM http://xlforum.net/forums/showthread.php?t=130964)) \\
+The center portion where the front bolt goes was left on below to help give support once the pushrods are adjusted. \\
+(in an attempt to help eliminate the chance of a leak).
+First start off with a good set of boxes. Spray a little layout die on them and lay them out for a reference line. ((photos by hoosier xlc of the XLFORUM http://xlforum.net/forums/showthread.php?t=130964)) \\
+|{{:techtalk:ih:engmech:splitting_rocker_boxes_1_by_hoosier_xlc.jpg?direct&300|}}|{{:techtalk:ih:engmech:splitting_rocker_boxes_2_by_hoosier_xlc.jpg?direct&300|}}|{{:techtalk:ih:engmech:splitting_rocker_boxes_3_by_hoosier_xlc.jpg?direct&300|}}|
+Set each box in a vice and mill down the center. Then weld up the oil passages where the split was made. \\
+And clean up the areas modified to smooth things out. ((photos by hoosier xlc of the XLFORUM http://xlforum.net/forums/showthread.php?t=130964)) \\
+|{{:techtalk:ih:engmech:splitting_rocker_boxes_4_by_hoosier_xlc.jpg?direct&300|}}|{{:techtalk:ih:engmech:splitting_rocker_boxes_5_by_hoosier_xlc.jpg?direct&300|}}|{{:techtalk:ih:engmech:splitting_rocker_boxes_6_by_hoosier_xlc.jpg?direct&300|}}|
+Lastly, you'll need to relocate the oil passages, and decide whether or not to polish or powder coat them. ((photos by hoosier xlc of the XLFORUM http://xlforum.net/forums/showthread.php?t=130964)) \\
+|{{:techtalk:ih:engmech:splitting_rocker_boxes_7_by_hoosier_xlc.jpg?direct&300|}}|{{:techtalk:ih:engmech:splitting_rocker_boxes_8_by_hoosier_xlc.jpg?direct&300|}}|{{:techtalk:ih:engmech:splitting_rocker_boxes_9_by_hoosier_xlc.jpg?direct&300|}}|
+====== Cut Down ======
 Cutting the middle down achieves 'the look' while keeping the rigidity and good gasket sealing. \\
 The trickiest part is making a shortened tap and keeping it dead on true to both holes so nothing binds on assembly of the crossover oil line. \\
-|These were assembled with Loctite and ferrule fittings. ((photos by JonesL of the XLFORUM http://xlforum.net/forums/showthread.php?t=1719533&highlight=splitting+rocker+box&page=5))||
+Getting plumbing in between those two holes is difficult. ((JonesL of the XLFORUM http://xlforum.net/forums/showthread.php?t=1998127&highlight=split+rocker+box&page=2)) \\
-|{{:techtalk:ih:engmech:split_rocker_boxes_3_by_jonesl.jpg?direct&200|}}|{{:techtalk:ih:engmech:split_rocker_boxes_1_by_jonesl.png?direct&300|}}|{{:techtalk:ih:engmech:split_rocker_boxes_2_by_jonesl.png?direct&300|}}|
+The shortened tap is necessary due to the tight space between the two holes. \\
+It helps for both surfaces to tap to have flat faces. \\
+Getting a tap started on an angle doesn't help you align a straight hole when tapping. \\
+Equally important, the two holes have to be in perfect alignment with each other. \\
+Going one way, you can put a guide pin in but coming back the other way, you have to rely on a sharp eye and a very steady hand. \\
+The plumbing goes together like a Chinese puzzle. \\
+Screw the assembled fittings in loose then slide the inner connecting tube in, making sure not to gouge one or both of the O-rings. \\
+Once the tube is in place screw the fittings into the boxes tight, then screw the ferrule nuts down tight. \\
-===== Fully Split =====
+Removal / installation after this mod: \\
+Don't mix up which box section goes where. \\
+Keep in mind the very small hole on the underside of the rocker arm. \\
+It's there to provide a little extra oil to the exhaust valve stem for cooling. \\
+The rockers can be swapped rear cyl exhaust for front cyl intake and vice versa so take care when assembling. \\
+|These were assembled with Loctite and ferrule fittings. ((photos by JonesL of the XLFORUM http://xlforum.net/forums/showthread.php?t=1719533&highlight=splitting+rocker+box&page=5)) ((http://xlforum.net/forums/showthread.php?t=1998127&highlight=split+rocker+box&page=2))|||
+|{{:techtalk:ih:engmech:split_rocker_boxes_3_by_jonesl.jpg?direct&150|}}|{{:techtalk:ih:engmech:split_rocker_boxes_1_by_jonesl.png?direct&300|}}|{{:techtalk:ih:engmech:split_rocker_boxes_2_by_jonesl.png?direct&300|}}|
+====== Fully Split ======
 |A piece of angle iron holds down the center bolt section and also serves as a place to the mount air cleaner/carburetor stabilizer brackets. ((photos by Tim The Grim of the XLFORUM http://xlforum.net/forums/showthread.php?t=1719533&highlight=splitting+rocker+box&page=5)) \\  Machined little oil coolers help add some extra cooling for the exhaust area.|||
 |{{:techtalk:ih:engmech:split_rocker_boxes_1_by_tim_the_grim.jpg?direct&200|}}|{{:techtalk:ih:engmech:split_rocker_boxes_2_by_tim_the_grim.jpg?direct&300|}}|{{:techtalk:ih:engmech:split_rocker_boxes_3_by_tim_the_grim.jpg?direct&300|}}|
+|In shop hand made lines. ((photos by ironheadjunkie of the XLFORUM http://xlforum.net/forums/showthread.php?t=1560224&highlight=split+rocker+box))|||
+|{{:techtalk:ih:engmech:split_rocker_boxes_1_by_ironheadjunkie.jpg?direct&250|}}|{{:techtalk:ih:engmech:split_rocker_boxes_2_by_ironheadjunkie.jpg?direct&250|}}|{{:techtalk:ih:engmech:split_rocker_boxes_3_by_ironheadjunkie.jpg?direct&250|}}|
+====== Other Split Rocker Box Pics ======
+|  75 XLH ((photo by fdny37 of the XLFORUM http://xlforum.net/forums/showthread.php?t=120623)) \\ These were split for the dual plug setup. ((photo by fdny37 of the XLFORUM http://xlforum.net/forums/showthread.php?t=130964&page=2))  |
+|{{:techtalk:ih:engmech:75_xlh_w_split_rocker_boxes_by_fdny37.jpg?direct&300|}}|
 \\

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