Robbie, the A23's seem to be notoriously difficult to mount certain tire sets on. Hell to put on Vittoria Rando 32's. Worse with Vittoria open Corsa sc's-literally blew out several tubes post mount while on the stand. Really wanted to mount those SC's so went to the plugs. Less mass in the rim means more clearance to mount the tight tires. End result was that both SC's went on much easier (as in, I could see myself changing one on the trail) and neither tube has blown in almost a week on the rack.
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Hard at work in the Secret Underground Laboratory...