Thanks for this as I’ve just built up a second hand one of these recently and had the same problems. As an engineer, it looks to me like there are slight tolerance build up issues in the overall assembly that then allows flex of the stem and then causes the bolts to relieve over time. I best add the loctite Mitch recommenced.

By the way, do people find the base bar/stem combo a bit flexy ? I’m coming from my old nosecone shiv which was rock solid but I’m finding the base bar assembly of the Trek doesn’t feel very stiff. Anyone got any thoughts on this ?