Valve cover change info.  Install using the following parts:

Use the following pictures to complete the install:

Drill valve cover as shown with 1/2" step drill, sand off a small amount of barb on one end of the 90 degree fitting and install into the aluminum tube and valve cover with "Right Stuff" sealer on all fittings and along the bottom of tube.  Drill and tie tube to cover with tie.


If there is enough room at the front of the cowling, just use the original exit and no need to relocate as shown above.  


  • New gasket only get right stuff sealer where head meets chain cover (split)
  • Shoulder bolts should be tightened down until shoulder bottom against head.
  • If wire loom is short, bring it straight down, rather than around front of cover
  • trim plastic wire covers as needed
  • Do not force any wires
  • Do not run a hose overboard from the tube since suction can be generated


  • Cleaner oil at oil changes
  • Virtually no oil blow-by

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  • I like this idea, but the Honda cover interferes with my cowl. I modified my cowl some time ago and unwittingly created a clearance problem with the engine, so the larger (Honda) cover won't work. I cut the front vent off as instructed, then removed more of that boss, but it's still a no-go. You could patch over that and use it as Jan suggests. I paid $181.65 at the Honda dealer. You can have it for $100 - including shipping. Contact me here, or at <> if interested. I'll send you pix.
  • Bill,
    I suggest you contact Norm Neuls

    He made a minor mod to the Viking valve cover rather than replacing it with the Honda cover.
    John N.
  • I am not up to date on what to do with my 110. I have been flying it with the original valve cover, and have not had any problems . The pictures that I see have a black cover instead of the aluminum one that came with it.
    Can I just modify that cover to install a vent, or do I need to get a cover from Honda?
  • There is no pressure. It is capped by the oil pressure housing. However, we seal each end with sealer as well
  • Jan, right after you posted the video for the new Honda valve cover, Robert Eli posted a question about the small o-ring in a cavity filled with gray Right Stuff at the upper, forward corner of the valve train. I have not found your response to that.
    I asked Don about it and he said it was originally the oil gallery for the variable cam mechanism (no longer needed) and that it was actually blocked off by the oil temp/pressure adapter above it. He's probably right, but I can't prove it. if he's not, then the Honda cover would allow it to blow out under oil pressure, so I should clean it out, tap it and plug it. If he is right, and there's no pressure behind it, then I'll clean it out and leave it alone. What say you ??
  • When I removed the original Aluminum cover, I discovered a small O-ring surrounding a hole in the head that was plugged with grey sealer. I assume that this O-ring is removed and I should clean out the sealant in the hole before installing the Honda valve cover? I remember this being discussed somewhere before, but could not locate that discussion. Also, I noticed that when I removed the shoulder bolts, they had been coated with gray anti-seize lube. Other bolts, such as those on the oil sensor fitting, have blue thread-locker residue. I have been unable to locate any instructions as to which bolts need anti-seize and which need blue thread-locker. Is there any guidance as to which to use where? It seems that it might be wise to use anti-seize on all steel bolts in aluminum threaded holes (in addition to spark plugs and the exhaust muffler).
  • Yes, the calve cover is a fresh air entry and we install a small filter on it.
    The exit hose should have a slight suction
  • So Jan, judging from your comments, this valve cover vent is providing an entry path for air to flow through the crankcase, not an exit. This would imply that the breather cap is the exit - otherwise there would be no flow. So are you running a hose from the breather cap overboard? I assume it is positioned to provide a slight suction?
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