Thanks for that information, 911. Never too old to learn, LOL. Figured if a place like Universal did not carry it, then it ain't out there. Anywho, if for whatever reason folks feel the need to drill out their rim to make room for a schrader valve/tube, then I hope they realize that the little insert there is going to have to go under the rim strip, lest they risk abrading and wearing the rubber surrounding the valve with that metal insert.There is a lot of misinformation on this thread... I'll start with this. Amazon.com : Quad Wheels Manufacturing Presta Stem Saver for Schraeder Rims : Bike Brakes : Sports & Outdoors
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In all of my years of riding and the other forum I participate in, I simply do not ever recall seeing anyone drilling a presta sized rim out for a schrader. I'd advise against it; the presta with it's locknut keeps that tube in place when mtb'ers air down to single digits.