Campy Racing Triple Front Shifting

[Hindmost]

So I've set up Racing Triple cranks and derailers with an 8-speed downtube shifter and 8 speed cassette. The chain is C10 and and the big and middle sprockets are matched 50/40 C10 triple. Chain is sized for big big with nothing left over (running a 28 rear cog seem to require this for clearance.)

Upshifting to the 50 used to be okay but after a few hundred miles it seems to have degenerated--pick up pins don't pick up anything and when the chain finally moves it wants to immediately over shift which the 8 speed cage will obligingly allow to drop to the outside. I've tried various outside stop adjustments to either push the chain or limit the outside movement. Neither really works well.

The cassette indexing is a little sketchy too but maybe that's a topic for a whole other thread.

Any suggestions?

[Ralph]

If you were running a Campy 8 speed Ergo shifter.....would advise matching chain to cassette, and making sure FD cable very tight. With down tube 8 speed index shifters, imagine same. If friction shifting....should have less issues would think.

[oldpotatoe]

Originally Posted by Hindmost

So I've set up Racing Triple cranks and derailers with an 8-speed downtube shifter and 8 speed cassette. The chain is C10 and and the big and middle sprockets are matched 50/40 C10 triple. Chain is sized for big big with nothing left over (running a 28 rear cog seem to require this for clearance.)

Upshifting to the 50 used to be okay but after a few hundred miles it seems to have degenerated--pick up pins don't pick up anything and when the chain finally moves it wants to immediately over shift which the 8 speed cage will obligingly allow to drop to the outside. I've tried various outside stop adjustments to either push the chain or limit the outside movement. Neither really works well.

The cassette indexing is a little sketchy too but maybe that's a topic for a whole other thread.


Any suggestions?

First the shifting on the rear..use an 8s chain, like KMC..10s chain is too narrow. Modern indexing systems require a chain that's wide enough so the next cog will effectively 'grab' the chain..Match the chain to the cogset 'speed's, not the chainrings

Maybe lower the front der and perhaps angle it so the front more effectively grabs the chain and moves it up..tail in..then limit screws.

[jamesdak]

Originally Posted by oldpotatoe

First the shifting on the rear..use an 8s chain, like KMC..10s chain is too narrow. Modern indexing systems require a chain that's wide enough so the next cog will effectively 'grab' the chain..Match the chain to the cogset 'speed's, not the chainrings

Maybe lower the front der and perhaps angle it so the front more effectively grabs the chain and moves it up..tail in..then limit screws.

I'll agree with this. Mine is running the proper chain and shifts just fine. Can't remember any misshifts or dropped chains. I think there may be some room for error on these as my front sits a little high but the right angle has it doing the job just fine.

[Mark McM]

Originally Posted by oldpotatoe

First the shifting on the rear..use an 8s chain, like KMC..10s chain is too narrow. Modern indexing systems require a chain that's wide enough so the next cog will effectively 'grab' the chain..Match the chain to the cogset 'speed's, not the chainrings

Maybe lower the front der and perhaps angle it so the front more effectively grabs the chain and moves it up..tail in..then limit screws.

I agree with the chain width issue. I also agree with lowering the front derailleur until is only about 2mm above the teeth on the big ring. But I think you'd want to angle the derailleur more tail out, not in. Tail in will tend to increase over-shifting (throwing the chain to the outside). Tail out will engage the chain sooner, but won't push it as far after it grabs the big chainring.

General rules of thumb: If the front derailleur has to be moved a lot before it engages the chain, but then pushes the chain too far (throws the chain off the chainring), angle the front derailleur more tail out: If the front derailleur engages the chain early, but won't push it far enough to reach the big chainring, angle the front derailleur more tail in.

[oldpotatoe]

Originally Posted by Mark McM

I agree with the chain width issue. I also agree with lowering the front derailleur until is only about 2mm above the teeth on the big ring. But I think you'd want to angle the derailleur more tail out, not in. Tail in will tend to increase over-shifting (throwing the chain to the outside). Tail out will engage the chain sooner, but won't push it as far after it grabs the big chainring.

General rules of thumb: If the front derailleur has to be moved a lot before it engages the chain, but then pushes the chain too far (throws the chain off the chainring), angle the front derailleur more tail out: If the front derailleur engages the chain early, but won't push it far enough to reach the big chainring, angle the front derailleur more tail in.

Yup, thanks, meant tail out..doh! Front ders can be vexing.

[choke]

I'm running a Racing T on a Campy 8sp triple (9sp chain) with the original rings so no ramps or pins. It shifts fine IMO.

As for the back, my suggestion would be to ditch the index DTs and go with friction.

[Hindmost]

My faith in Tullio has been restored.

New 8-speed KMC chain and front derailleur cage bottom pushed out ever so slightly. Front shifts up and down no problem. The chain appears the right width for the derailleur cage to protect against over shift.

Rear shifting is a more crisp across the cassette. Still doesn't quite center on some of the middle cogs sometimes. Nudge the lever and it centers. (The 8 speed downtube shifter has next to no wear; I wonder if it's a cable drag thing, all there is is a bottom bracket guide and a short housing.)

I'm pleased to resolve this. Based on the source of the suggestions I shouldn't be surprised by the outcome. Thanks all.

[oldpotatoe]

Originally Posted by Hindmost

My faith in Tullio has been restored.

New 8-speed KMC chain and front derailleur cage bottom pushed out ever so slightly. Front shifts up and down no problem. The chain appears the right width for the derailleur cage to protect against over shift.

Rear shifting is a more crisp across the cassette. Still doesn't quite center on some of the middle cogs sometimes. Nudge the lever and it centers. (The 8 speed downtube shifter has next to no wear; I wonder if it's a cable drag thing, all there is is a bottom bracket guide and a short housing.)

I'm pleased to resolve this. Based on the source of the suggestions I shouldn't be surprised by the outcome. Thanks all.

Which generation? The type with the YUGE knurled knob with friction option? Make sure the bolt that attaches the shifter to the frame isn't too tight.

[Hindmost]

The shifters are C Record up to 1994, 2 G-springs. (The centering issue became less apparent as I rode this morning.) What a pleasure to ride without any shifting drama. Weird how fat the 8-speed chain appears, though it's scaled right for the derailers.

A related question:. Does the Racing Triple rear derailleur wrap up spring have multiple tension settings? If so, is one preferred?