Originally Posted by
SethAZ
If the OP were really interested in maximizing his performance, he'd be asking whether he's got the right bike, then the right accessories on the bike, the right tires, the right clothes and helmet, etc. Eventually, way down near the bottom of the list of every conceivable factor that might have a measurable impact on performance, one would find the question of whether a given inner tube was patched or not. This question would probably be just behind whether to shave one's eyebrows, and just ahead of whether or not one should wax the frames of one's sunglasses.
How do we know he hasn't already done all those things?
Not to belabor the point, but everyone who rides on tubes will eventually be faced with the choice of whether to replace a tube or patch it. It is just as reasonable to ask whether patched tubes impact rolling resistance as it is to ask whether latex tubes are faster than butyl, or whether one brand of tube is faster than another. If I knew that a patched tube cost me half a watt, it'd be worth an extra few dollars a year to replace tubes in my race wheels. If I knew it dodn't matter, I'd save the few bucks and spend them on something else.
I'm glad the OP asked the question, and I'm glad that folks like Chung and Poertner are discussing the hundreds of small choices we all make that determine whether our equipment is as efficient as it can be.