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Old 12-18-09, 06:37 PM   #1
JunkYardBike
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Campagnolo Ergo rebuild

I'm working on a 9 speed Mirage/Veloce drivetrain that has problems shifting from 1st to 2nd cog and 3rd to 4th cog on the cassette. It worked fine for about 800 miles before the problem appeared. Shifts fine in all other gear combinations.

Chain wear is way less than .75%.
Chain length has been measured large chainring to large cog + 1 link.
Can't find any stiff links.
Cassette cogs are barely worn.
Derailleur hanger appears aligned (never crashed or dropped).
As a test, I completely removed the B tension screw to ensure the upper wheel is as close to the small cogs as possible. Still no go.
Replaced the RD cable and lengthened the rear cable housing a bit (it was tight, but worked fine for 800 miles and for previous owner).

I spend nearly 4 hours 'repairing' the right shifter. New index spring carrier, ratchet bushing, and index "g" springs. Nearly lost it trying to get the spring coil bushing to seat (this took 3.5 hours).

The index spring carrier was cracked, so I thought for sure it would solve the problem. Wrong. All other mechanicals appeared in good shape. The shifters probably have less than 1500 miles total on them.

Could it be the rear derailleur itself? I'm thinking it's still in the shifter - it's just not pulling enough cable from cogs 1-2 and 3-4.

Other ideas?

Last edited by JunkYardBike; 12-18-09 at 06:46 PM.
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Old 12-18-09, 06:56 PM   #2
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Appears aligned and is aligned are not the same. A hanger can be misaligned enough to cause shifting problems while still not be visibly out.
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Old 12-18-09, 07:00 PM   #3
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Appears aligned and is aligned are not the same. A hanger can be misaligned enough to cause shifting problems while still not be visibly out.
Well, it's a steel hanger, so I fiddled with it quite a bit, and in each position it still gave me the shifting problems on those same two cogs.
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Old 12-18-09, 07:00 PM   #4
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Well, it's a steel hanger, so I fiddled with it quite a bit, and in each position it still gave me the shifting problems on those same two cogs.
That is the incorrect procedure. You need an alignment gauage to properly align it. You may also want to make sure you're actually adjusting the rear properly: http://www.parktool.com/repair/readhowto.asp?id=64

You most likely screwed it by fiddling with it without a gauge. 9+ gear systems are not very tolerant of hanger misalignemnts. This might not necessarily be the problem but you need to rule it out. It's top 3 causes of shifting problems.
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Old 12-18-09, 07:11 PM   #5
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That is the incorrect procedure. You need an alignment gauage to properly align it. You may also want to make sure you're actually adjusting the rear properly: http://www.parktool.com/repair/readhowto.asp?id=64

You most likely screwed it by fiddling with it without a gauge. 9+ gear systems are not very tolerant of hanger misalignemnts. This might not necessarily be the problem but you need to rule it out. It's top 3 causes of shifting problems.
Yeah, I don't want to hear that. I suppose a proper tool would come in handy - it seems bikes with bent derailleur hangers have a habit of finding me.

Still, I'd like to hear if anyone has had similar issues with Campy Ergos before I dump more money on the problem. The replacements parts already cost more than the shifters are worth.
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Old 12-19-09, 10:46 AM   #6
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About the ergo levers. I take it that you did not replace the index gear, but that should not be the issue if the shifters have only 1500 miles on them. If they had 10,000 or more it would be a possibility. Isn't it amazing how the guy on the youtube video can put a ergo lever together in about 5 minutes? It always takes me more like 15. I'd say you didn't have good instructions to follow. It should not take hours, but there are a few tricks to it.

The big problem I see here is you want good shifting, but you are not willing to do the job right and follow the manufacturer's instructions. Taking the B screw out is never recommended. There is a specific distance from the top pulley to the largest cog.

The advice to get the RD hanger aligned is also sound.

You didn't mention the chain brand, but if you have a Campy chain, it can be shot and show less than .25% elongation. Side plate clearance is rearely measured, but it can affect shifting. I've had Campy chains show little elongation even after 6,000 miles, but the chain had a lot of side flex due to the wear. If you can place a feeler gage thicker than .012 inch between the inner and outer plates, I'd consider the chain to be shot.

I would also ask if the shifting problem is only in one direction, particularly from the larger cogs to the smaller ones. That could be due to cable friction.

If I suspected a cable pull problem, I would measure the cable pull so it could be ruled out. I've measure cable pull lots of times, but only because I wanted to know the amount. All it requires is a precision machinist's scale and a some masking tape. I shift the thumb button all the way down and wrap a piece of tape around the cable, a precise distance ahead of the cable stop on the chainstay, then measure the increase in the measurement after each shift. You should get the same amount for the first 4 pulls, then an increase for the next two and another increase for the last two. I've only measured 10 speed shifters, so I can't give the exact amounts for 9 speed. I do have a publication that says it should be about 3.2mm or shifters older than 2001 and 3.0mm for shifters 2001 or newer. 10 speed shifters average about 2.8mm, but the actual pulls are 2.5mm 5 times, 3mm twice and 3.5mm twice.
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Old 12-19-09, 11:13 AM   #7
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About the ergo levers. I take it that you did not replace the index gear, but that should not be the issue if the shifters have only 1500 miles on them. If they had 10,000 or more it would be a possibility. Isn't it amazing how the guy on the youtube video can put a ergo lever together in about 5 minutes? It always takes me more like 15. I'd say you didn't have good instructions to follow. It should not take hours, but there are a few tricks to it.
Please do share your tricks. The trouble I had, as described above, was setting the spring coil bushing. It wouldn't catch, I think, because the return spring was interfering.

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The big problem I see here is you want good shifting, but you are not willing to do the job right and follow the manufacturer's instructions. Taking the B screw out is never recommended. There is a specific distance from the top pulley to the largest cog.
??? I posted a thread to seek more experienced advice, and I'm receiving it. Not sure how that qualifies as not willing to do the job right? I took the B screw out because I've got a large cog of 29T, and I know that on some systems setting the B screw to clear a large cog can affect shifting on smaller cogs. I was simply eliminating that as a factor. I suppose I failed to mention this is a triple drivetrain setup.


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The advice to get the RD hanger aligned is also sound.
Agreed. I've ordered the Park alignment gauge.

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You didn't mention the chain brand, but if you have a Campy chain, it can be shot and show less than .25% elongation. Side plate clearance is rearely measured, but it can affect shifting. I've had Campy chains show little elongation even after 6,000 miles, but the chain had a lot of side flex due to the wear. If you can place a feeler gage thicker than .012 inch between the inner and outer plates, I'd consider the chain to be shot.
It's a Campy C9. I don't have a precise chain length measuring tool, so I can't measure to .25% wear. However, I do have a feeler gauge. .012 wedges between the plates, but .013 doesn't. However, all other things being constant, it sounds like the chain might be the ultimate culprit.

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I would also ask if the shifting problem is only in one direction, particularly from the larger cogs to the smaller ones. That could be due to cable friction.
It's from small to large, and only from 1-2 and 3-4.

Thanks for your well informed assistance!
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Old 12-19-09, 11:39 AM   #8
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I'd get a new chain and check the hanger alignment. If the chain skips on one or more cogs while pedaling under a heavy load, a new cassette will also be needed.

About the ergo lever, getting the last piece into position can be tough. I always mount a 5mm hex wrench in a vise and use it to hold the ergo lever by the end of the main pivot shaft. That shaft must be held stationary, so pushing on the spring coil bushing does not allow the shaft to be pushed down. The thumb lever spring can be pushed to the side with the bushing, to let the bushing engage the pivot shaft. I've temporarily installed the center fixing bolt, just to hold the bushing in place, then installed the big wind-up spring. The tail of the spring can be slipped under the fixing bolt, then the other end swung around to the post on the g-spring retainer. It is the toughest part of the job. The new ultrashift levers are MUCH easier to work on, but the don't come in 9 speed.

Since you have a triple with a 13-29, you must have a long cage RD, not a medium cage. I tried that with a medium cage and could not avoid contact between the 29T cog and top pulley. Make the chain as long as possible. If you have a typical 52/42/30, set the length in the little ring and smallset cog, to the longest that causes the lower pulley to swing forward a bit and produce some chain tension. If you have a smaller little ring, you should expect chain sag with at least a couple of the smallest cogs and little ring.
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Old 12-19-09, 12:01 PM   #9
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Thanks for all the help.
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Old 12-29-09, 08:13 AM   #10
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Park Tools DAG-2 arrived the other day. It's not the dropout hanger alignment. Chain replacement next...
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Old 01-02-10, 03:10 PM   #11
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I've replaced the chain. Still the same problem.

I replaced the rear derailleur with a lightly used Veloce 9 speed medium cage. Same problem.

I failed to mention earlier that I did modify the cassette in the past. I needed lower than the 23T it came to me with, so I added a 26T and 29T. The drivetrain didn't complain for the 800 miles or so I rode it until the problem cropped up. However, the shifting problem does occur where I removed two smaller cogs. So, where it used to be arranged as 12-13-14-15-16-17-19-21-23, I changed it to 12-14-15-17-19-21-23-26-29. It only exhibits the problem when shifting 'up' from 12 to 14 and up from 15 to 17.

Sooo, I reinstalled the cassette in the original configuration. Although the problem now occurs with less frequency, it still occurs.

I don't think it has to do with the wear on the cassette, as I'm guessing it has fewer than 2000 miles on it.

I still suspect the shifter. I also replaced the rear derailleur cable. I suppose housing would be the next step, but if the problem is friction, I think it would shift poorly across the entire range of cogs, and especially when it shifts to smaller cogs.

The cog teeth:




Last edited by JunkYardBike; 01-02-10 at 03:17 PM.
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