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Old 09-04-11, 08:03 PM   #1
Zap Hassellhoff
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ST-2200 Front Derailleur Shifter Issue. WARNING long winded.

Hey all,

Sorry for the lengthy post.

I have an issue that has really stumped me. Let’s assume that everything is installed based on Park Tools Big Blue Book, Shimano instructions and Sheldon's advice.

I’m in the process of upgrading my Trek 400 from 105 7-speed downtube to 8-speed STI. I have installed a pair of Shimano ST-2200 “sora” shifters. I’m using a 105 1056 front derailleur, rear derailleur and crank. The BB is 107mm matches the crank, based on Sheldon’s recommendation.

The right shifter indexes perfectly to an 8-speed cassette, no problems. The left shifter/front derailleur, on the other hand, is giving be some serious problems.

When I up-shift, the shifter will shift the chain to the large chainring then settle back inboard about 2mm or so. This will force the chain to rub on the inner face of the front derailleur. If I continue to toggle the shift lever to the right, the derailleur will pull slightly outboard off the chain and hit the high set screw. But once I release the lever the derailleur will settle back inboard again and start rubbing.

I have raised, lowered and twisted the derailleur in every conceivable way.

It seems that the only way I can get the derailleur off the chain is to increase the tension on the barrel adjuster on the downtube. When I do this, the adjustment seems excessive, to the point that it pulls the front derailleur out so much that it starts messing with my low setting. I’ve played around with the “bow technique” for increasing initial cable tension but that seems like a jerry-rig and I don’t like it.

I thought it might be a derailleur issue so I tried an older 1050, and a newer 5600 series. The problem exists with all of them.

In short the indexing of the front shifter does not produce enough “throw” to get the cage far enough out to clear the large chainring to even begin adjusting the high set screw.

Is this play in the left front ST-2200 shifter common and if so, what are my options to increase the outboard range of the derailleur, short of maxing out my barrel adjustor?

Sheldon seems to argue that that derailleur should not make a difference. However, should I install the matching FD-2200 unit and see if that syncs up with the shifter. Or should I say screw the STI and buy some bar-ends? I need to stimulate the economy right?

I look forward to any comments.

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Old 09-04-11, 08:12 PM   #2
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Originally Posted by Zap Hassellhoff View Post
It seems that the only way I can get the derailleur off the chain is to increase the tension on the barrel adjuster on the downtube. When I do this, the adjustment seems excessive, to the point that it pulls the front derailleur out so much that it starts messing with my low setting.
How exactly does the low setting get messed up? Are you unable to downshift? Do you get rub?
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Old 09-04-11, 10:18 PM   #3
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Sorry, perhaps I'm not being clear.

This is how I set the low derailleur limit: On the small chainring without the shift cable installed, I down shift into the lowest gear (cog). I then back off low limit screw the front derailleur until there is about .5mm-1.0mm of gap between the inner face of the derailleur and the chain. I then make sure the the shifter is clicked down, my barrel adjustor is about 1/2 a turn out and then install the shift cable.

Now, when shifting up using the st-2200 shifter, the front derailleur completes the shift but retracts about 2mm causing the chain to rub on the inner cage. To trim this, I use the barrel adjustor to pull it further out off the cahin. Drawback is that I create so much tension on the cable that it prevents the derailleur from fully downshifting.
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Old 09-05-11, 12:03 AM   #4
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It seems that it should be normal for the shifter to "overshift" a fraction and then pull back. This extra nudge would then help get the chain to ride onto the chainring's teeth.

I don't know anything about your crankset. Possibly it was designed for 6/7 speed systems and has wider spacing between the rings than what we see on 8-sp cranksets.
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Old 09-05-11, 06:15 AM   #5
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What is the center to center front chainring spacing?

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It seems that it should be normal for the shifter to "overshift" a fraction and then pull back. This extra nudge would then help get the chain to ride onto the chainring's teeth.

I don't know anything about your crankset. Possibly it was designed for 6/7 speed systems and has wider spacing between the rings than what we see on 8-sp cranksets.
Hi it would be useful to know the front chainring spacing on the bike - just use a ruler - that is close enough - center to center - it will be either 1cm or about 6mm or so, but measure it and note it on this thread. Regards, Honestron, London
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Old 09-05-11, 06:26 AM   #6
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I have had a lot of trouble with front STIs shifting properly. It just seems to be very sensitive to my crappy skills, as well as the exact, perfect, mounting of the derailleur, the model and more. I had a 105 setup, never could get it right, so I swapped FDs with what I had in the bin, a RX100 shifter, and it worked great. As luck would have it, the next bike I worked on was all RX100, had problems with the front shifter. So I went back to the bin, the only thing I had left was the 105 derailleur I pulled off the prior bike. You guessed it, the 105 derailleur worked great on that bike.
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Old 09-05-11, 01:40 PM   #7
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Originally Posted by wrk101 View Post
I have had a lot of trouble with front STIs shifting properly. It just seems to be very sensitive to my crappy skills, as well as the exact, perfect, mounting of the derailleur, the model and more. I had a 105 setup, never could get it right, so I swapped FDs with what I had in the bin, a RX100 shifter, and it worked great. As luck would have it, the next bike I worked on was all RX100, had problems with the front shifter. So I went back to the bin, the only thing I had left was the 105 derailleur I pulled off the prior bike. You guessed it, the 105 derailleur worked great on that bike.
For some reason, this made me laugh.
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Old 09-05-11, 06:03 PM   #8
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I recently did the same conversion back in June for my wife. The only part I did not change out on the 400 was the front mech. Instead, I tried my luck and simply left it on. Other than a little adj. on the low side stop, it works great with the STI brifter.
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Old 09-06-11, 02:31 PM   #9
Zap Hassellhoff
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Thanks everyone fo the comments and suggestions.

Yea, I'm thinking that for some reason the ST-2200 shifter does not mesh well with the 1056 crank. Why, I'm not sure, perhaps the large chainring sits to far out. As I said above, I consulted Sheldon's BB index sheet and he stated that a 107mm BB is typically used.

Hmm. maybe I should try another crank.

Also, I have tried a couple different front derailleurs with varying degrees of success. I though about buying a matching FD-2200 derailleur and giving that a shot.
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Old 09-06-11, 08:43 PM   #10
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Quote:
Originally Posted by Zap Hassellhoff View Post

In short the indexing of the front shifter does not produce enough “throw” to get the cage far enough out to clear the large chainring to even begin adjusting the high set screw.
Were you threading the cable through the front derailleur correctly? There's a tab on the top of the washer on the cable pinch bolt. The proper way to thread the cable is OVER this tab, not under, then between the washer and the derailleur. Threading over the tab increases the length of the throw slightly, to spec.

We had a Specialized Secteur come into the shop today with lousy front shifting. Somewhere someone threaded the cable wrong, and when we re-threaded it, presto!
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Old 09-12-11, 10:34 AM   #11
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Hi everyone,

Thanks again for all the comments and suggestions. So I solved this issue. I took a chance and picked up a matching FD-2200 front derailleur for $10 shipped off of flea-bay. It has plenty of range to clear the large chainring and trim with the high limit screw. No kickback or chain rub at all.

I'm not in love with the asthetiecs of the piece. But it functions perfectly with the 2200 shifter. Who would have guessed, parts in a group wourking together?

I've learned a valuable lesson.
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