I'm doing a valve adjustment now on the bike and having trouble to catch the real gap. Initially, after bike been ridden and cooled down for a day I checked the gaps and these were almost good, except for a couple bit short. After pulling the shims out for measurement and putting everything back together and remeasuring the gaps these became much tighter, the more I was trying to cycle the engine to seat the things properly, the tighter it was becoming....however I do not believe that cycling it would effect the gap and push oil out from between valve stem, shim and bucket and so on....anyway the new gaps are still much tighter than before disassembly. I'm experienced enough in this field and have not seen this happening before, all shims and buckets were taken out only as single pairs and there is no way these could be misplaced and so on. Additionally all shim pair were exactly same thickness from factory. Checked the gaps at different lobe position of the cams, but same results Any ideas or similar experience with 990?