Differences
This shows you the differences between two versions of the page.
Both sides previous revision Previous revision Next revision | Previous revision Last revision Both sides next revision | ||
techtalk:ih:engmech04a [2019/06/14 02:07] hippysmack [Pros and Cons of Functionality] |
techtalk:ih:engmech04a [2019/06/14 19:23] hippysmack [Pros and Cons of Functionality] |
||
---|---|---|---|
Line 2: | Line 2: | ||
====== IH: Engine Mechanicals - Sub-04A ====== | ====== IH: Engine Mechanicals - Sub-04A ====== | ||
====== Splitting Rocker Boxes ====== | ====== 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)) \\ | 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'. \\ | Otherwise you've just invented a new 'chinese puzzle'. \\ | ||
Line 9: | Line 12: | ||
**Pros**: \\ | **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)) \\ | 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. \\ | 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**: \\ | **Cons**: \\ | ||
Line 27: | Line 44: | ||
Your pushrods are doing the same thing 29 times a second at 3500 rpm. \\ | 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 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)) \\ | 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) \\ | (or optionally replace it with a hard shim) \\ | ||
Box flex is real and it doesn't have to be. \\ | 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)) \\ | 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 54: | Line 80: | ||
That is better than splitting the boxes. \\ | That is better than splitting the boxes. \\ | ||
- | ===== Cut Down ===== | + | 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. \\ | Cutting the middle down achieves 'the look' while keeping the rigidity and good gasket sealing. \\ | ||
Line 78: | Line 125: | ||
|{{: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|}}| | |{{: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 ===== | + | ====== 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.||| | |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|}}| | |{{: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|}}| | ||
\\ | \\ |