Campy 8 speed - shifting trouble

Greetings to the group!

Tuning my rear dérailleur has proven impossible.
Some gears not shifting at all and some gears shifting two at a time.

I don't know where to start. I am wondering whether its my ergos/ rear derailleur combination??

I am using these exact Campy record ergos:

http://velobase.com/ViewComponent.aspx?ID=4f7f7c56-c2b6-448a-ba79-6e4a2c3e36b7&Enum=125

with an Athena 1st generation 8 speed rear dérailleur that came with a friction shifting group:

http://velobase.com/ViewComponent.aspx?ID=61B0737F-8BE5-4FB9-A00B-A8860B84AF7D&Enum=108&AbsPos=3

Is it because I am using the older friction shifting derailleur or should I be looking elsewhere??

Assuming none of the parts are dirty/damaged/worn then the combination should work.

If you haven't done so already, remove the cable, check for any damage, lubricate and replace. Then slacken off all the tensioners and the limit screws and start from the beginning.

I'm not going to detail every step of dérailleur setting but there is a good step-by-step guide on the Park Tool website.

Many thanks for the feedback!
I did try a few times to re tune (my lbs also had a go) but no luck!

Could an over-tighten lockring on the cassette mess up its spacing??

Other causes I am considering:

• messed up cassette (other spacing or sprockets)
  
• messed up free wheel
  
• bent derailleur
  
• bent frame/ cable hunger
  
• messed up ergo shifter
  

They're all possibilities. Bent link in the chain also a possibility.

You just need to carefully examine each component for damage.

Do you have the right cassette? With the right spacers?

If it's the wrong derailleur, the cable pull might mean that the derailleur is not moving the right amount across the cassette with each 'click' of the shifters.

check the cassette is installed correctly?

Cheers guys!

From your feedback I take it that the shifter/derailleur combination could work so I will start my investigation elsewhere! !

The cassette came with the wheels and it was already installed.

I bought the wheels as a mavic/Athena 8 speed wheelset and asked the seller to add a campy 8 speed cassette.

I don't think its the chain as it was a new chain installed by my lbs when I completed the built.

I can share pics once I am back home!

The cassette came with the wheels and it was already installed.

doesn't mean it was done properly.

I'm not convinced that derailleur will have the same cable-pull/actuation ratio as a later 8-speed indexed derailleur.

General things to watch out for are:

Dirty or sticky cables,
Overly worn jockey wheel
Lateral play in the main rear derailleur pivot (whole mech rocks side to side if you grab it).
Worn G-springs in shifters (gear change is noticeably sloppy and not "clicky" at all).

agreed !!! Need to acquire a lockring tool in order to inspect/ re install!

You can check with caliper that you have the correct 5mm spacing between sprockets. Obviously measuring across multiple rings improves your measurment accuracy.

Rodabod mentioned g springs, this is the most likely cause of your shifting problem, these are in the shift levers and are a pain to replace, but doable if you follow instructions carefully (YouTube). Parts can be got from Downland cycles.

Many thanks for the valuable input.

I did hope it wouldn't come to that (ergo rebuilding) but it probably makes sense.

When I start from the smallest ring I need to overshift by quite a bit to get the derailleur to stay in second gear or to over tension the cable which messes up the rest of the gears!

Are there any tests I could run to confirm this theory??

Indexing tends only to work well with derailleurs with a slant parallelogram design. It looks like your derailleur does not have this feature but maybe its just the picture.

I am back home so I had the chance to investigate further.

Cassette spacing:
Was not easy to confirm with calliper but I am quite sure that spacing is consistent as the calliper fits snugly in-between all the rings.

Before rebuilding or acquiring new ergos I wanted to establish that they are the cause of the problem. I have noted the following which may be useful for confirming that the ergos are the problem:

1) When shifting up there are times when the dérailleur shifts into gear but does not stay there (it shift back down).
2) To shift up from the smallest ring I either need to overshift or to overtension the cable (hence messing up the rest of the gears).
3) When I pull the naked cable the shifters clicks and dérailleur shifts down.

Any feedback appreciated.

Also if anyone has a spare set of ergos pls let me know. I will also post in classifieds/wanted. Could be interested in 9 and 10 gear as well as I am also considering upgrading my wheels!

I'm not convinced that derailleur will have the same cable-pull/actuation ratio as a later 8-speed indexed derailleur.

I really think this is your problem.

^ and again, so do I!

Cost wise it does make more sense to start from the dérailleur if this is a 50/50 bet !

So does anyone want to sell me an 8 speed (ergo compatible) rear dérailleur :-)??

I'm pretty sure that's a 7-speed mech. Unlikely to have the correct cable-pull/actuation ratio, and maybe not even linear in its ratio.

Just out of interest, does the 8 speed system still require the derailleur cable to be pretensioned by a kilo? I've a 9 speed and following the Park Tools guide I completely missed that I had to do this, and the gear shift was terrible, until it was pointed out to me.

Now, when i do the gears, I release the cable, push the rear derailleur to the between the second and third sprocket, tighten the cable up and release. It seems to give the cable the correct tension.

Hi all

I was able to find a Veloce 9 speed rear mech to purchase.

Before purchasing I wanted to see if anyone can confirm that it will function properly with my 8 speed ergos and Cassette?? (i.e. does it have the same cable pull actuation ratio).

Within a given brand of indexable rear derailleurs, all "speed numbers" are generally interchangeable

That's what Sheldon says

Cant go wrong : -)

Cheers !

Search for "Shimergo".

In answer to your question, yes, it will work (I've done the same), though it'll be slightly more susceptible to poor shift when it gets dirty, or when parts get worn.

The good thing about using a 9-speed mech is that it's likely to be newer.

Coming late to this one - but another suggestion. Are you routing the gear cable correctly to the fixing bolt on the rear derailleur? In general I think the routing should be to the 'bottom side' of the bolt. Routing incorrectly to the 'upper side' of the bolt changes the cable angle and the amount of movement when changing gear. I found this solved a similar problem I had with Campy 8 speed.