I swore the decompressioner had a spring on it, but when I took it off the stock cam to put on the Hot Cam, there wasn't a spring. We put it on anyway and I haven't noticed anything wrong with it or any weird noises either. I'm sure if a spring is supposed to be there it makes it work correctly. What's the worst that can happen without a spring? Would it just not work? I saw this picture on ebay and it made me wonder about it though.