From:Dave Molnar
Subject:RE: De-luxe valve caps Date:Sat Aug 31 16:11:05 2013
Response to:4813
Hey Sverre, Congratulations!!! I love to hear about people out there riding there bikes! So far I have 18,000 miles on mine!

For those valve caps...

I hate those copper rings!! They always seem to leak loosing what little compression you have! Also I have had a cap come loose going down the road!!! that is an awful noise and you get that sinking feeling that terrible things are going on down there! Then you shut down and coast to a stop. There is one of the caps sitting nicely on top of the cylinder!!! PHEW!!!

I do lots of crazy things! Believe it or not I use permatex "copper" silicone and no copper ring at all. I just wipe around the threads and install. I give a couple light taps on the cut-off box end (32mm?) wrench and that's it. They never leak and never come loose (unless you want them too...) I also use it on the spark plugs! I have used the high heat black silicone too as an alternative but I like the copper version.

What seams to happen is the material dries out within the threads and keeps a good seal. when you remove it, the fist 1/8 turn (tapping) makes the dry silicone turn to powder and out the cap comes. A little of the dust falls in to the cylinder when you remove the cap and you can get it out if you want. Its so fine and a tiny bit, it just blows out anyway. When I have the cap almost unscrewed, I stop and blow away the loose powder before removing the rest of the way.

I use original valve caps so I don't have any experience with the ones Bill has.

Hope this helps,


Had my longest one day ride on the Henderson last weekend. Rode 400km`s on single lane country roads, including two mountain passes.

The first pass is kind of different from most mountain passes over here, as the climb is done by two very long straight hills, which the old De-luxe did easily in third (I thought). Having stopped at the top of the mountain for a while I found the exhaust valve on the rear cyl had frozen in open position when I was to continue my ride.
I had my 8" long home made valve plug wrenchlong with me, the one that I used to tighten the plugs after my renovation. I couldnt move the plug to get access to the valve, no chance. Had to ride to a nearby tractor workshop (on a three cyl Henderson) where we ended up using a 50" long arm on a power socket, using a hammer on the socket top to shock the threads.
When I finally got the plug removed the threads was OK and I could easily turn the plug back in by hand????
I dont understand why the plug was so hard to get out? I had used Never-Seez high temp compound on the threads before assembling.
Plugs where bought from Bill at St. Louis Henderson parts, great parts I think.
Anyone experienced the same problem??
Now I am seriously worried about the remaining exhaust valve plugs.

Kind regards
Sverre Gerber
AMCA 3489