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Re-gearing Problem
#1
For faster speeds, I changed the front and rear gearing on my road bike (new 7-sp freewheel and new triple crankset). After adjusting the front and rear derailleurs the bike shifts great in all gears with only one gearing exception....
with the chain riding on the middle chain ring and the rear at the outer most or smaller cog, the chain tries to shift up to the higher chainring, but can't complete the shift due to the front derailleur guide. This creates a jerking motion of the pedals. Since the chain is positioned in this gearing, at an angle to the front middle chainring, its what's causing the problem.
Since it's only in one gearing position, I can shift around this problem without to much trouble, but it would be nice to eliminate this.
I checked the front chain line dimension and it is correctly positioned at 45mm per the crankset installation manual.
Where should the rear freewheel cogs be located? I could adjust the rear freewheel position by removing one 2mm spacer that I installed to make the cogs line up with the old freewheel. Would a different chain help?
The bike is new, so the chain is new also. Thanks for the help.

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#2
I wouldn't worry too much about where any of these parts are "supposed" to be. Since you've changed everything, it's just a matter of getting them where they work. If you can remove a spacer on the freewheel to move it to the left, that should eliminate the chain rubbing on the largest chainring. Make sure to re-adjust the limit screws and cable tension on your rear derailleur. If you made extreme changes to the gearing ratios, you may have trouble getting the gears to run smoothly in all combinations. But taking out that spacer sounds like a good experiment.

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#3
I finally figured out what the problem was. Turns out when I swapped the crankset, I also had to change the bottom bracket. I used a 68x111 as per the Campy chain ring installation guide.
I just switched to a 68x115 bottom bracket and the problem went away. I had been riding around this shifting problem. So, by just moving the chain rings out further, I now have the full use of the gearing.

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