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Old 08-04-10, 07:14 AM   #1
Farby
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help me dial in my FD

So i have followed the steps on the park website and the campy booklet, but can't seem to get my FD to not rub when i'm in front small ring and the last 2 or 3 small cogs in the back.

what am I doing wrong? The large ring and all gears work fine with no rub.

How loose or tight are the adjustment screws on the derailleur supposed to be when you first set it up?

any tips or thoughts on what to try? This is my first time doing this so any help is much appreciated.
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Old 08-04-10, 10:17 AM   #2
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do you have a micro adjustment on your shifters? Are you running a double or triple. If it's a triple, then there really isn't a need for you to spend much time in little, little. But, if it's a double, you're looking at the micro adjusting (like a half shift) or adjusting your tension on your cable so that the rub doesn't happen (more tension on the shifter will cause it to move toward the next ring up on the front, and provide more clearance for the chain).

The other thing that can cause the rub is if the fd is not straight, ie, if it's angled, to check this put the der as close as you can get it to directly over one of the chainrings, and stand over it, see how close to parallel they are, it should be very close to parallel.

A third option to kind of "cheat" is to angle your fd "out" just a bit, to allow for more clearance in those outer gears, but this may have unwanted results on the lower gears, as it may then rub when in small/big combo, which you will indeed need, regardless of double or triple setup.

Joe
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Old 08-04-10, 10:23 AM   #3
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So i have followed the steps on the park website and the campy booklet, but can't seem to get my FD to not rub when i'm in front small ring and the last 2 or 3 small cogs in the back.

what am I doing wrong? The large ring and all gears work fine with no rub.

How loose or tight are the adjustment screws on the derailleur supposed to be when you first set it up?

any tips or thoughts on what to try? This is my first time doing this so any help is much appreciated.
Reread the park instructions, they tell you exactly how to set it up. You're doing one or more of the steps incorrectly if you're getting the symptoms you're describing. Start from the beginning, and do not skip any steps.

Campy derailleur setup instructions are worthless.
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Old 08-04-10, 12:14 PM   #4
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I don't think you have done anything wrong. If nothing else is rubbing you have done a great job. What you are experiencing is what is called being "cross chained" you have your chain going from your smallest gear in the front to the smallest gear in the back causing the chain to look like \ when looking down on it. You want to make it look like | and be straight. That gear ratio is not normal to be in. The rider should shift into the middle ring before depleting all the higher gears in back. Im not sure what joseph and operator are saying but if im reading you correctly it seems you are in good shape.
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Old 08-04-10, 04:39 PM   #5
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Originally Posted by josephjhaney View Post
do you have a micro adjustment on your shifters? Are you running a double or triple. If it's a triple, then there really isn't a need for you to spend much time in little, little. But, if it's a double, you're looking at the micro adjusting (like a half shift) or adjusting your tension on your cable so that the rub doesn't happen (more tension on the shifter will cause it to move toward the next ring up on the front, and provide more clearance for the chain).

The other thing that can cause the rub is if the fd is not straight, ie, if it's angled, to check this put the der as close as you can get it to directly over one of the chainrings, and stand over it, see how close to parallel they are, it should be very close to parallel.

A third option to kind of "cheat" is to angle your fd "out" just a bit, to allow for more clearance in those outer gears, but this may have unwanted results on the lower gears, as it may then rub when in small/big combo, which you will indeed need, regardless of double or triple setup.

Joe
Ok, not sure what micro adjustment is. Where can i find it? I am running a double. it's 2008 chorus group. I wasn't sure about cable tension when i was setting up and was playing with a little looser a littler tighter for a while until i got close like it is now. the cable was already running from the shifter so i wasn't sure how tight to pull it when i was tightening it down to the F/D.

The FD looks exactly or almost exactly parallel.

You are right that if I angle it out i get rub on the lower gears.

another question, how close should the crank arm come to the F/d when in 53/12?
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Old 08-04-10, 04:47 PM   #6
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I don't think you have done anything wrong. If nothing else is rubbing you have done a great job. What you are experiencing is what is called being "cross chained" you have your chain going from your smallest gear in the front to the smallest gear in the back causing the chain to look like \ when looking down on it. You want to make it look like | and be straight. That gear ratio is not normal to be in. The rider should shift into the middle ring before depleting all the higher gears in back. Im not sure what joseph and operator are saying but if im reading you correctly it seems you are in good shape.
I know i typically wouldn't ride in that combo of 39/12, but I am getting rub on the last 3 small cogs of my cassette so i know something is up. I feel like i should be able to get it set up so there is no rub at all in any gear combo because thats how it was operating before I had to replace it. Of course that was set up by the mechanic at the shop!
I really want to get this so i don't have to rely on a shop like i always have in the past.
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Old 08-04-10, 05:01 PM   #7
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......but can't seem to get my FD to not rub when i'm in front small ring and the last 2 or 3 small cogs in the back.

what am I doing wrong?......
Wrong? Nothing at all. You're just expecting too much. The small ring in front and smaller 2 or 3 sprockets in the back is considered to be severe cross chaining and should not normally be used at all. consider the buzz it make when the chain rubs on the FD cage as a warning that it's time to shift to the middle ring. Which to my mind makes your FD tune totally perfect. You can't ask for more than a safe and finely tuned cross chaining warning system....
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Old 08-04-10, 05:25 PM   #8
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If you have the cage aligned so that it is parallel to the rings and the low limit screw set properly as you say you have then you may be expecting too much from your system. You should have some rub in the last two, or three gears. You can also shift up only one click of the shifter lever to "trim" the FD. Front Derailleur systems have relied on some sort of trimming to dial out noise. Hell, sometimes the chain rubs on the outer ring when you get down into those cross chaining gears. Now that is something you cant dial in.
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Old 08-04-10, 05:29 PM   #9
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The OP has a double crank; I don't think it's asking too much that the inner chainring of a double crank has access to all cogs in back. (Edit: Granted, depending on the geometry of your setup, it may not be possible.)

I have no experience with Campy, but aren't their front shifters quasi-friction with multiple positions to somewhat-fine tune the derailleur?

I would disconnect the cable and start over. Make sure the FD is as parallel to the chainrings as possible. Set the low limit screw so that the FD inner cage gets as close as possible to the chain while in the little/big combo without rubbing.
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Old 08-04-10, 05:34 PM   #10
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Oops, I don't know all the groupos in detail to realize that it's a double. If that's the case then yeah, it should be able to access all rear settings with no rub. But that assumes an ideal chainline centering between the rear and front clusters. If it's out a little for whatever reason then it'll be difficult to achieve perfection. Or to achieve it the FD cage will need to be aligned with and fine tuned with the "median line" between the two clusters rather than directly fore and aft.
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Old 08-04-10, 06:14 PM   #11
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Oops, I don't know all the groupos in detail to realize that it's a double.
Yes, because the statement "I am running a double" in post #5 was oh-so cryptic. Just kidding, I overlooked it the first time.
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Old 08-05-10, 07:02 AM   #12
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Yes, there should be a way to fine tune that, I know on my Tiagra setup there are actually two positions for each gear. In all the way down bottom of the low end, I can get to 1-7 of my rear gears, if I go to 8-9, I get chainrub, but I can "microshift" (Not sure on the proper term, but I push the lever about half as far as I would for a normal upshift, and click, it moves the FD over just enough so that I can hit the last two gears without rub. Now, if I would happen to go back to 1,2, or 3, with the microshift set to the higher end, I would then get rub on my inside of the FD. Same is true for the 53, but not as much, since the FD is actually closer to the ring on the 53 when I'm in it than it is on the 39. But there are two click settings there to.

I was surprised how much microshifting is needed, I had never ridden a double before, and was not aware of the "1 low, 1 high, 2 low, 2 high" shifting before last week when I switched over.

Oh, and congrats to you for grabbing a wrench and having at it, I love working on my own stuff, it's like therapy. Though, I hate working on it when it's cutting into my riding time, nothing better than finishing up riding for the night, and coming home to a nice cold beer, and a set of bike tools to do some fine tuning, or replace a part. Ahhhhh.

Joe
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Old 08-05-10, 07:15 AM   #13
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With a double crank it takes 3-4 clicks of the finger lever to shift from the little ring to the big ring. Any more indicates too little cable tension and/or too much clearance between the chain and left side of the cage in the little ring and largest cog.

When you push the thumb button all the way down to the little ring, you have 1-2 clicks of the finger lever that can be used to trim the FD to the right. That's all it takes to stop the rub.

Campy escape shifters work a little differently. There is only 1 click on the thumb button to drop the chain onto the little ring, but there should still be a trim click on the finger lever for trimming the cage to the right.
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