I bought a 2010 Schwinn Paramount Series 7 on June 21st, and it had nothing but shifting issues with the Shimano 105 componentry. I had it back and forth to numerous shops no fewer than 10 times within that period of time.
The chain would slip while climbing steeper grades, the gears would slip either or down while climbing those same steep grades, if all of the rear gears worked right when the front chainring was in one gear, they wouldn't work in the other (it didn't matter whether it was the large chainring or the small one), rear gears would skip and hunt, I'd have to tap the shifter twice to get a gear to switch, etc.
I finally had enough of hearing, "Just fine-tune the barrel adjusters," or "There's a break-in period." I had ridden this bicycle no fewer than 200 miles since purchase. I'd say that's more than enough time for a "break-in period." Not to mention, the additional costs from having to trek this bike from one bicycle shop to the next, some of which were 50 miles away.
On Tuesday morning I returned to Performance Bike upon their customer service department's request and exchanged the bike for a replacement. I rode the replacement bike around the parking lot, trying out the gears, and they seemed to work okay, but the problem is that there aren't many hills in Fairfax, VA. To simulate a hill, I'd press the rear brake to build drag, and everything worked fine.
I got home with the bike, went out for a spin, and sure enough, everything went to Hell. Once again, I'm having issues with the bicycle, and they are the SAME, EXACT ISSUES as I was dealing with before!
What is up with this Shimano 105 stuff? I keep hearing about how it's the "industry standard," and it's "good ****," but I'm going to beg to differ. Here I am with a $2000 (retail) road bike and I have nothing but problems with it, and this is the SECOND one! My wife has a $380 mountain bike that doesn't have these sorts of issues, and the mountain bike takes a beating!
Somebody PLEASE tell me what's up with this Shimano 105 stuff, because I think 105 are piles of absolute ****.
I've given this bicycle until the end of the month to be sorted, and if not, I'm returning it, period. It's disappointing, because this is the bicycle that I chose and I want, but I'm not going to continue to deal with this bs on a $2000 bicycle.
Not feeling confident, I'm already looking at my other options, but to my dismay, they too, have Shimano 105 componentry.