Campy Shifting Prob

[mdeeds71]

Well its done...will post pics this weekend...My colorado II from the early 90s is complete in all its new paint and centaur parts...

But...I tried to dial in the shifting using Campy's instructions and get a problem with down shift to the smaller cogs only when on large chainring...I only get it in the 5-8 cogs and it is sporadic...everything is new...but cannot understand what it is doing...If I relax cable tension then the upshifts suffer on the same cogs...Could this be a chain tension problem???

Any idea...also the campy directions had me tighten all the way the screw on the guide pulley cage...is this tension???

[saab2000]

Hey Mark,

How's the flying? I'm getting my stuff in with CO soon. AWAC is putting me in PHL for Sept. and Oct. and then after that I will be DCA based...... Strange times these.

Anyway, are you sure that your chain is the right length? That is quite important. Also, make sure that your limit screws are proper. I am sure that you have checked that, but it is important.

But what is sounds like you have is the following. Make sure that when you attacht the cable to the rear that it is already in the smallest cog. After you have it all in and have shifted a few times you will probably have to adjust the cable tension. The cable will have stretched a bit - enough to throw off the shifting. It is not totally uncommon for the shifting to be a bit slack in the smallest couple of cogs.

Finally, make sure that the derailleur hanger is straight. There is a special Park tool for this and if the dropouts or der hanger are not properly alligned it can really throw off your shifting.

1. Check chain length.
2. Check cable tension in the smallest cogs. In your smallest there will be a bit of slackness in the cable.
3. Check allignment of the dropouts and derailleur hanger.

[mdeeds71]

Good luck with CO...I have to wait for my senority number for myself...that will be a while...

Is the tension adjuster the one that is on the pivot point and how slack should it be??

Again only happening on the big ring so I am assuming more a tension issue???

I have adjustable dropouts with the thumbscrews...I might not have these quite aligned any suggestions??

[saab2000]

Well, I probably won't be competitive with CO, but it never hurts to try. I am not sure about going to Guam though.....

The cable barrel adjuster is attached to the rear derailleur where the cable meets up. It is hard to define how tight it should be. I am suspicious that you have a chain length issue here. I am a bit nervous that it might be one or two links short. Did you shorten it according to the instructions? This is actually fairly important and a short chain will compromise shifting, especially in the big ring and big cogs.

The dropout screws should not be an issue here, though they could be. If the wheel is dished correctly you should not have to have much adjustment of these as I think we can assume that the Serotta frame is properly alligned. These screws exist primarily to correct for minor issues. If the wheel is centered between the chainstay then you are alright.

The only reason there would be any misalignment of the frame would be because of a crash and it would probably be the derailleur hanger.

You may wish to have a shop mechanic look it over. Wish I could be of more help.

[Proxy]

Well its done...will post pics this weekend...My colorado II from the early 90s is complete in all its new paint and centaur parts...

But...I tried to dial in the shifting using Campy's instructions and get a problem with down shift to the smaller cogs only when on large chainring...I only get it in the 5-8 cogs and it is sporadic...everything is new...but cannot understand what it is doing...If I relax cable tension then the upshifts suffer on the same cogs...Could this be a chain tension problem???

Any idea...also the campy directions had me tighten all the way the screw on the guide pulley cage...is this tension???

they have tons of pdf's on most everything - once the small cog and pulley are in alignment and the low cog does not spit the chain into the wheel then everything is cable tension. for the chain length, put it in the big chainring and low gear and give it a 2-link overlap, thats all you have to do.

[DfCas]

You might check to make sure the cable is anchored at the correct spot.Although it may be in the groove,it is sometimes possible for the little tripod shaped thing to get turned,really whacking out the shifting.My experience has been you just throw Campy parts on and if its even close,they work well,so I suspect something is drastically wrong.

While you have the cable off,make sure it moves freely in the housing.I've seen even new housing bind the cable.

Hope this helps,dan

[Dave]

Chain length would rarely affect shifting precision. The right way to set chain length is to the maximum that will keep the chain from hanging slack or rubbing on the upper pulley chain guide tab, with the chain in the little ring and smallest cog. The chain can only be shortened in 1-inch increments, which is equivalent to 4 cog teeth. When set to the maximum length, the RD will handle any cassette within the RD's wrap capacity. Ashorter chain will not improve shifting precision, it just limits the RD's wrap capacity.

As others noted, be sure the thumb button is all the way down and the chain is in the smallest cog when the cable is attached to the RD. Also be sure that the cable tension adjusters are screwed most of the way in before attaching the cable. Be sure the cable is attached to the correct side of the clamp bolt. It usually take several turn on the cable tension adjuster before the 1-2 shift will execute.

When the cable tension is set properly it will NOT have any slack in it. Once the shifts from the smallest to the largest cogs all execute properly, there is enough tension on the cable. At this point, if shifts from large cogs to smaller ones hesitate, it's usually due to a cable FRICTION problem. This means that there is excessive friction that the spring in the RD cannot overcome. Be sure all cable ends are cut square and the teflon lining is not damaged near the cable ends. I always apply a thin lube, like Slick 50 1-lube to my cables and housing. Be sure the cable guide under the BB shell is not worn out and it it lubricated. Be sure that the end of the cable in the ergo lever is seated properly and there is a ferrule on both ends of all cables. Be sure that the cable between the chainstay and the RD is not too short. A tight bend here, or lack of lube can cause excessive friction.

You don't mention the age of your ergo levers, but it's always possible that they are not functioning properly. I lube mine at least once a year with Slick 50 1-lube. It's best ro remove the hoods and wrap a rag or paper towel near the base of the ergo lever if lubing while on the bike. Too much lube will run down and oil up the bar tape.

[mdeeds71]

I have it now shifting...believe it or not...I found that the rear drive side had pulled a little off the stop screw in the dropouts. That made sense to me since the chain line on the larger seemed to have more "alignment" with the cogs that were slipping...But Campy has you set up the shifting using the fourth cog as the guide for the indexing on the rear d, some on this thread talk about the shift from first to second as the guide...both worked for me.

The chain is long enough to go from the largest in rear to the large chainring in front without going through the RD and an extra link as per guidance on several sites.

My FD is a little finicky on the up shift.

I have it set using the guidance by campy as the outside parallel with the chainring. It seems to have a lot of resistance going up in terms of friction between the inner cage and the inner part of the chainring, almost like it want to lock the chain but it always shift up just losses a bit of cadence doing this.

[Jeremy]

My FD is a little finicky on the up shift.

I have it set using the guidance by campy as the outside parallel with the chainring. It seems to have a lot of resistance going up in terms of friction between the inner cage and the inner part of the chainring, almost like it want to lock the chain but it always shift up just losses a bit of cadence doing this.


It often helps to have the rear end of the cage angled outward just a bit. This changes the angle of the front edge of the cage and it often eliminates the symptom that you describe. You do not need to do much, but you will pronbably need to adjust the inner set screw again so that you get a crisp downshift and no chain rub in the lowest gear.

Thanks,

Jeremy

[saab2000]

Yup, my advice is bad. Sorry. I guess years of using only Campy has left me with no knowledge of how it works. Also, years of working in shops working on the stuff has left me with no knowledge of how it works.

Sorry I chimed in with my bad advice.

Mike, not referring to you here.

[Dave]

Excuse my poor attitude. Ten lashes for me. Cable friction is the most common problem when shifts from larger to smaller cogs becomes erratic and reducing cable tension makes shifts in the opposite direction poor. I was surprised none of our highly experienced posters caught that.

Adjusting chain length is very straight forward. There are all sorts of tricks that are recommended, like routing the chain around the big ring and largest cog and adding a link, but any method that uses the big/big combo can lead to problems if the cassette being used when the length is set has less than the maximum number of teeth and later a cassette with more teeth is installed. The little/little or better yet, the little chainring and second cog is the best way to adjust chain length. Either one should produce the same result, since one tooth is only equal to 1/4 inch of chain.

Two simple tests will determine if the chain is the correct length. First, it must not hang loose in the little ring, little cog combination. If there is no tension on the chain in the little ring, little cog combination; remove two links (one inch) at a time, until there is. When the ends of the chain are brought together, some movement of the lower pulley should occur, indicating tension is being applied. Two more links (another inch) may need to be removed, beyond the point of absolute minimum tension, to keep the chain from rubbing on itself or the chain guide tab as it passes under the upper derailleur pulley. If you want to see how much lower pulley movement will occur, without removing the extra inch of chain, shift up four teeth (11 to 15 or 12 to 16). This has the same effect as removing two links. Once this is done, the chain is set to the maximum useable length. Removing additional links will do nothing but reduce the derailleur's capacity.

Second, the chain must be long enough to avoid over-extending the rear derailleur when shifted to the big ring and biggest cog combination. If the chain is set to the maximum length as described, it should always pass this test, unless your setup exceeds the derailleur's stated wrap capacity. If you deliberately exceed the derailleur's capacity and the derailleur is over-extended in the big ring/largest cog combo, then you must either avoid that combo or add another inch and avoid using the little chainring and the smallest 3 or 4 cogs (since the chain will hang loose).

[David Kirk]

It actually sounds like cable drag to me..........are you sure that the cable slides throught the housing smoothly and with very little friction? Check the ends of the housings where they were cut to be sure that you don't have a burr that is grabbing the cable.

Dave

[mdeeds71]

I have the RD now dialed but know the first few rides the cables will get stretched...Ended up the rear was slightly out of alignment with the drop set screws...Only friction I could find was on the bottom bracket, old style casted guides with new repaint=a little bit of tension. Got the front a little better but need to pronate the nose like mentioned to add a bit of movement.

Great help...From EVERYONE...including the Air Wis pilot...

[saab2000]

No Prob Dude. Just tryin' to help a brother out. Welcome on the jumpseat anytime! Even if you fly the jungle jet!! I guess ours is just the Barbie Jet, or Lawndart as the United dudes call it so fondly. :beer: