Strengthening the valve hole of a rim during manufacturing Various technologies(sleeved, soldered, pinned) exist to reinforce the place where the rim makes full circle. A major argument against Schrader valve is it's large diameter weakens the rim. I, however, enjoy that valve and was wondering the following. Are there rims* with AV and proper strengthening around the air hole? Just like seat tube reinforcement. * - let's say intended purpose is enduro riding style (drops up to 1m), mid-level budget(300EUR for wheelset); but any technologies are of interest!

The question is a misnomer. In the earlier days of mountain biking, Schrader was the more common and the rims were much wider. The size of the hole is a real issue for narrow road rims and the narrow XC rims that became more common into the late 90s.

I have a set of the very first Mavic CrossMax wheels which were very very light XC race wheels and these are drilled for schrader without apparent reinforcement, and profided with a small plastic shim for presta valves. The strength of the rim around the valve hole was never an issue for this incredibly light rim. You may find reports of its other weaknesses though, when used for too heavy an application.

Modern MTB rims are again wide, very wide, and you shouldn't be concerned about the size of the valve hole in these. where the manufacturer allows a schrader. It's personal choice (&risk) if you decide to drill a presta hole to take a schrader valve, of course, but that's not in the scope of your question.