Good advice this...all of it. Your cables do stretch during the first 100 miles or so, causing sketchy shifting. I also have a 105 front and Ultegra rear and had the same issues when I first got my bike....but since my first tune-up it has been perfect. The eonly upgrade I could even think of at this point would be clipless pedals if you don't already have them. Otherwise, congrats and enjoy that nice ride. Upgrade fever can really bite you if you're not careful.
Cheers,
Brian
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“A good teacher protects his pupils from his own influence. ”
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