Increasing travel on Shimano Acera front derailleur

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Helping a neighbor kid get a bike going. She was gifted the bike, and doing some training for a triathalon. Chain broke and destroyed the front derailleur, had a tiagra, odd model, replacements were $40-50. I picked up a tiagra that I thought would work for $15.

Well, I apparently didnt read enough of the myriad of specs on shimano front derailleurs, I couldnt get enough travel to set limit on snallest front chainring.

Heres the "salvage the situation" fix
 
I found the positive stop that limits the cage movement towards the frame. The limit screw acts on the other side of this. I needed more travel towards the frame and this was blocking the travel.
Closed
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Open
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I carefully ground the face of this. Checking movement as I went to increase travel.
After grinding
20200823_111956.jpg
 
Gave me just enough room to get the chain off the cage in small front cog, large rear cog to set this up.
20200823_113118.jpg
20200823_113144.jpg



Not ideal, better front derailleur chiice would have avoided it.

Might come in handy for others here as we mix and match components that we have on hand.

Took the bike for a ride, trek road bike, showed her how everything works.
Rear derailleur seems to have been bent. I straightened the cage, middle 4 gears of the rear cassette are notchy, the ramps look worn. But it will get her riding and training. If they want to spend money on parts ill continue to offer a hand.
 
It just wouldnt adjust far enough to get off the chain on small sprocket. Now it does. :rofl:
5 gears or so is plenty for me. Im really digging internal gear hubs, bought one recently havent gotten it laced up yet.
Did a schwinn for my Dad with a Sturmey kickback, very cool
 
Square taper wear in can cause this. A bigger offset spindle is what I have done which is as much a pain as what you did. I have an 80 s mountain bike that now needs a longer spindle so i might try this. To go the opposite direction I have used shims to get the right chain line on a road bike to fixie conversion.
 
Good tip on the crank alignment.
The issue with travel, there wasnt enough, likely from me choosing a replacement derailleur that may not have been compatible. Thought it was applicable ratrodbikes since we all mix and match.

Im not a big fan of front derailleurs, this was a kids roadbike for triathalon, didnt think she'd be OK with ditching it.
 

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