Amel

Hi,

I recently received an old Vivente World Radenneour from a mate which had been very poorly maintained. I'm in the process of getting everything working again and am struggling getting the front derailleur to shift correctly.

The front derailleur is a 3 speed Shimano deore xt. To get the gears to shift from inner most to middle chainring I've got to remove all tension from the cable, and shift it twice to on the shifter. This then makes the cable very tight and I really have to force the shifter to get it to click over and shift to middle chainring.

This still happens when I've adjusted the position of the front derailleur height and alignment as per the Park tool instructions (not allowed to post links) and adjusted the lower limit screw to ensure that any movement of the shifter translates to movement of the derailleur.

The shifters are Shimano Sora. This is gradually driving me insane so any advice anyone has would be greatly appreciated! I guess I could take it to the LBS....

JohnDThompson 

First, you need to isolate the problem. Disconnect the cable from the derailleur and move the derailleur directly, by hand. Can it sweep all three chainrings smoothly, without binding? If not, lubricate all the pivots generously and work the derailleur through it's sweep to see if it comes free and moves smoothly. If not, replace the derailleur.

Next, the cable. Are there any abrupt bends or excessive loops of housing? Sometimes, whoever set up the bike initially didn't bother to trim the housings to optimum length. Pull the housings off the cable and look for rust, kinks in the housing, splayed housing ends, etc. Trim or replace as needed. If the cable is rusty, frayed, broken strands, etc., replace the cable.

Finally, the shifter. With the cable disconnected from the derailleur, operate the shifter. Does it move smoothly through its range, and if indexed, click into place appropriately? If not, lubricate generously and keep trying. Still no joy? Replace the shifter.

HTH…

dsbrantjr

You should adjust the lower limit screw to provide a 1mm or so clearance between the chain and derailleur cage when in small front big rear combination then leave it alone. You adjust the indexing for proper shifting from small to middle ring.
Also, ensure that the front shift wire is correctly routed to the clamp screw; it usually goes OVER the little tab above the screw, not direct. If you go direct you shorten the lever arm, increasing the needed effort and throwing off the indexing.

Retro Grouch 

^^^^
This: It's a common issue, it's easily overlooked and it's counter intuitive.

Andrew R Stewart 

Sora is a road group, Deore XT is a MtB group. Shimano never intended the front shifters and ders to work properly together. The amount of cable that the shifter pulls isn't what the der wants. Also the earlier MtB cranksets also were slightly wider, the rings were spaced a tad further apart, so the ft der had to travel further to effect the shift. This miss match is usually discovered by "no amount of cable tension fiddling will help" type of playing around.

The der limit screws have nothing to do with cable tension. "and adjusted the lower limit screw to ensure that any movement of the shifter translates to movement of the derailleur" What the limit screw will do WRT cables is to change the base point of no further inward or outer travel and thus how the inner or the outer rings and cage line up against each other. The cable can be set as loose or tight as can be with any screw position. Andy

Bill Kapaun

You have a "road" shifter & "mountain" FDER. They have different cable pull ratios. One must be changed to match the other.
9 speed & less rear is generally cross compatible.

Amel

Turns out that it was this! So very frustrating. Thanks for all the assistance, much appreciated.

LV2TNDM

Housing ages over time. Eventually, it imparts so much friction on the system, it renders indexed shifting impossible. If you have to push or pull hard on the shifter to get it to move, it's probably a housing problem. Lubing and cleaning are useless. Damaged housing and housing ends, or ferrules cause problems too. Replace housing to restore "like new" shifting. Cut ends square, grind flat (if you're obsessive like me) and install ferrules. Lube with non-petroleum lubrication. Make sure housing is as short as possible, while still maintaining proper curvature and can accommodate handlebar turn.

Front derailleur position is important too. Height from chainrings as well as angle on seat tube are critical. Mixing road and non-road components causes problems. Road rings are too big for a mountain derailleur. And as was mentioned, mixing shifters also causes problems. Clamping the cable on the wrong side of the arm can also be the culprit. And then there's the dreaded "Campy-itis" many front derailleurs suffer. Especially the old ones. Old front derailleurs needed a custom bend to the front of the inside plate to induce proper shifting into the big ring.

So many factors at play!