Hello, this is my first post. My wife bought me a 99 955i for christmas and since then i've been trying to gather information. It has many modifications; triple clamps, rear sets, rear shock linkage are all attack racing. I want to adjust the preload on the rear but the owners manual says not to do it myself and i could "lose control of the bike and be seriously injured or killed". Why can't i adjust it myself, the suspension looks pretty standard to me.