I'm trying to do some research on identifying what valve springs were used in the KK. The parts books say they used the same 18201-52 spring that the K uses. The factory document that shows the instructions for installing the "Special Roller tappet Kit 18489-53R" also known as the "Competition Cam Kit" seems to indicate a different spring was used P/N RO 168-32. More on that later. I may start a KK specific thread to address some of the KK issues.
I have a couple sets of both K and KH valve springs. All are used springs. I know these all came out of K or KH cylinders as I have never had anything other then K or KH cylinders around. I decided to check these springs out for free length and compare them to the specs in the Shop Dope Service Bulletin "Valve Spring Testing Information". All the springs vary slightly but a median numbers are K - 2 9/16" and KH - 2 21/64".
It turns out that they all measure approximately 3/32" longer then what the specs show in the bulletin for free length. If anyone happens to have some loose original Harley valve springs around could someone measure them for length and post it. Is the document in error or are all my springs incorrect somehow? OK, I'm going to ask what may be a stupid question but one I have no answer to. When valve springs get weak do they relax and possibly get longer, or shorter, or no change in length but just simply get weaker and stay the same length?
The Special Roller Tappet Kit instruction document says that when valve is fully open spring should be within 1/32" to 1/16" from being solid. I am assuming that measurement is taken between the coils. Is that
a fairly standard spec for setting up any K valve spring?
Stan