Originally Posted by
PistaDalMine
Is the chain a Dura-Ace chain? If it is alot of people don't know that Dura-Ace chains have a front and back side u will notice on the chain it says Dura-Ace on one side and not the other. Side with Dura-Ace faces out very important my chain was doing the same as yours. The 7900 chainring has special pickups on the teeth to help it move up to big chain ring. The Chain is kinda rounded on one side if u look at.
Here is Tech Doc on it
http://techdocs.shimano.com/media/te...9830682232.pdf
The bike came with a KMC chain. I only have a few hundred miles on the bike but I got around to measuring the chain at it was already at 12 1/8" for 12 links. So I replaced it with an Ultegra 6700 chain before the posted videos. The writing is on the outside. Is that the only thing that matters? I imagine there isn't an up or down to the chain also, just inside/outside. The fact that it happened with an old and new chain should be telling...somehow.
Since the bike is new I took it in for the tune-up a few weeks ago. Didn't seem like they even touched it. I might call the shop and complain and see if they can give it a closer look. I hate paying for bike mechanic work stuff though, I like to do most of it myself, which is why I asked here. I might take a closer picture of the issue tomorrow. I appreciate the ideas.