43 road miles on wobbly knobbies means you're workin' too hard and could go faster, smoother. The quickest for now fix would be to switch to some narrower, slick 26" tires made for mtn bike road use. You'll notice the difference. Most major manufacturers offer up bikes for the road that are midway between mtn bikes and conventional racing bikes. If road is your new zone, you may well work your way across the bike spectrum towards that Lance clone Madone. But there's lots of good stuff between.
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..... "I renewed my youth, to outward appearance, by mounting a bicycle for the first time." Mark Twain, Speeches
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