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Discussion Starter · #1 ·
I have an OCR1 with a 9 sp Shimano triple setup. I have adjusted the front DR per the tech sheet (downloaded from shimano.com) several times, and I'm pretty sure it's right.

However, the bike will not run silently in all 27 gears. Something will always rub. For example, middle chainring and largest (or smallest) sprocket. Or smallest chainring and smallest sprocket. Biggest chainring and biggest sprocket. Etc etc. If I adjust to eliminate one rubbing combo, another will pop up.

According to the directions, the DR is only adjusted with smallest chainring, largest sprocket, then largest chainring, smallest sprocket (i.e. all the way in, all the way out). Someone locally told me that 'extreme chainlines' can't be expected to be smooth, and should be avoided. I feel that the bike should be smooth across all 27 speeds.

What say you???

ElGuapo
 

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Easy answer: no. It doesn't necessarily run quietly in ALL gears. In the extreme combo's of big/big and small/small, it's not at all unusual for a triple to have some noise ... so ... don't use those combos.

Some drivetrains have a problem at the most extreme two or three combos. There's usually no reason to use those combos anyway.

That doesn't mean, however, that you've done everything right--do you need spacers? Is everything torqued/aligned right?? Have to verify that stuff first.

Good luck!
 

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You do know about trimming the front derailleur, right? Just checking.
I don't bother adjusting to get the small/small or big/big combos to work, other than making sure that shifting into either won't break anything (in case I do it accidentally during a ride). Some people say that you shouldn't run the middle ring with the large or small cogs, but I use it with the large cog. It's a little noisier then, but I ignore it.
 

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Yup. I know about trim. Got an Ultegra triple on my touring bike.

I haven't personally seen a properly set up triple that had rub in the middle ring on any of the rear sprockets. I don't particularly think you should have any rub there either.

If you're avoiding the big/big and the small/small and you're STILL having problems ... then I'd say you still have something wrong. Again, it could be the fit/installation of your bb, your cassette, or your FD. Could be a cable tension issue ... a kink ... chainring bolts ... need for spacers ... it could also be just a less-than-perfect FD and RD setup & adjustment issue.

Have you gone through the entire drill for setting up and adjusting derailleurs -- step by step -- from a website like Park Tools?? If you've done that patiently and meticulously and STILL have an issue ... I'd prolly take it in to a shop....
 

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acceptable chainlines..

A triple has a much different chainline than a double. The middle ring is in nearly the same location as the big ring on a double. That makes the middle ring and largest cog a too-extreme chainline for all but occasional use. The middle ring and smallest cog is OK.

The big ring should not be used with the two largest cogs.

The little ring should not be used with the two smallest cogs.

If you exclude all of those combos and still have FD issues, then you've got an adjustment problem. That's why I like Campy - there's no separate "trim" positions to worry about.
 

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Spacers?

Where do spacers figure into this equation? If spacers are required that implies a work around for something more fundamental that isn’t right. If the all of the following are correct, I would not think that spacers would be required anywhere.

Frame, straight and properly aligned
Rear derailleur hanger, properly aligned
Front derailleur mount (if “braze-on”), positioned correctly and properly aligned.
BB shell, within spec (68 mm +/- .5mm), properly faced, threads chased
BB spindle, correct length
Rear hub/cassette, spacing correct, (not altered from factory specs)
All cables and housing properly installed and working correctly

Please pardon my ignorance. My bike mechanic skill were learned working in a “racing” shop back when dinosaurs still roamed the earth. I am frantically trying to catch-up with all of the technical developments of the last 15 years. Thank you for tolerating the questions of a troglodyte.
 

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I don't see anything ignorant about your question at all. I think you're dead on. Spacers--like shims--are fudge factors. In cases like this, I think they'd be employed to compensate for a problem in exactly one of the areas that you described.

I think your implication--that it's better to fix the underlying problem than to bandage the solution--is spot on.

I'm guessing, though, that lots of bandages get applied anyway....
 

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Discussion Starter · #8 ·
So what I'm hearing here is this:

So long as the FD will shift all three chainrings, and not toss the chain off either side, that's about the best you can get. Some chainlines are just going to rub slightly.
 

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So what I'm hearing here is this:

So long as the FD will shift all three chainrings, and not toss the chain off either side, that's about the best you can get. Some chainlines are just going to rub slightly.
Yes. Triple-setups on road bikes will always be twitchy - even the Ultegra and Dura-Ace level components (if you think its bad now, wait until you see the 10-speed versions). If you aren't dropping the chain or missing shifts between the rings, then you've probably got it setup pretty well - anything more than that is pretty hard to get on a triple, ergo the advent of compact.
 

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try campy...

gmcastil said:
Yes. Triple-setups on road bikes will always be twitchy - even the Ultegra and Dura-Ace level components (if you think its bad now, wait until you see the 10-speed versions). If you aren't dropping the chain or missing shifts between the rings, then you've probably got it setup pretty well - anything more than that is pretty hard to get on a triple, ergo the advent of compact.
Most posts about poor shifting come from shimano users. After 18 years of doubles (the last 8 on campy), I switched to a campy triple 3 years ago (for the mountains). I've setup numerous cranks and FDs and never had much of a problem. Never dropped a chain off the little ring or between rings. I just switched to the new campy ultra narrow chain and the shifting is even better. With the improved shifting, I'm going to change my gearing habits a bit and use the little ring a bit more often.
 

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C-40 said:
Most posts about poor shifting come from shimano users. After 18 years of doubles (the last 8 on campy), I switched to a campy triple 3 years ago (for the mountains). I've setup numerous cranks and FDs and never had much of a problem. Never dropped a chain off the little ring or between rings. I just switched to the new campy ultra narrow chain and the shifting is even better.
Agreed. I put a triple Record setup on my road ride for the same reason: mountains. Did it take me a tweak or two to get it right? Sure. But once I did, I get 26 out of 30 silently. If I don't hear rub, I don't reject a combination. From maybe the only "scientific" study that I've ever seen about gearing and energy loss, the closest thing to 100% energy transfer was the big/big combo.

If you're bored, bored, bored....

http://www.ihpva.org/HParchive/PDF/hp50-2000.pdf

I know; it puts extra wear on a drivetrain. Much? If you're not fully x-chained ... I doubt it, but what do I know?
 

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true...

Most folks don't know what they are missing. Most of my local shops have 99% shimano bikes-sometimes there's not more than one campy drivetrain in the whole (large) store and certainly no triples.
 

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a little...

A 1cm shorter chainstay only changes the angle a small fraction of 1 degree, but yes it does make some difference. The only time I expereinced a chainrub in the little ring and second cog on a double was on a Litespeed Ultimate, which had very short chainstays (and a curved seat tube).
 
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