Back in the day, Campagnolo had a touring component group model called Rally (RALLY).
I don't have the original vertical Rally, so I prepared a Nuovo Record from the same era.
Oops, my hand slipped.
The original Rally shares the same pantograph design as this Nuovo Record.
／：：：：：：：：：：：：：＼
＼：：：：：：：：：：：：：／
↑It looks like this — squares arranged like a clock face with Clous de Paris patterning, with the word RALLY written on top.
About vertical and horizontal derailleur designs.
When the frame mounting bolt and the pulley cage pivot bolt are roughly on the same axis, the pantograph orientation becomes vertical when mounted to the frame — that's vertical type. When the relationship between the frame mounting location and pantograph position forms an L-shape, causing the pantograph to become horizontal when mounted — that's horizontal type. Modern rear derailleurs are basically all horizontal type.
This rear derailleur is from the final generation Rally, the horizontal type version.
It doesn't say "Rally" anywhere, but the model name is definitely Rally.
Being a touring component, the pulley cage is extremely long.
I used to think that no road derailleur would ever exceed the pulley bolt spacing of this Rally.
The pulleys are white, so this is from the same era as C Record.
This white pulley is 10T, but even if a rear derailleur with a larger capacity rating existed, if it had larger-tooth pulleys, the pulley bolt spacing wouldn't necessarily be longer, so in terms of length competition, the 10T pulley final Rally has the advantage.
Some people occasionally say "Didn't Shimano realize the advantages of large pulleys?" but back in the 9-speed 7700 era, only Dura-Ace adopted large pulleys.
↑This one
The pulleys properly bear the Dura-Ace marking.
Before the real answer comes back, let me tell the truth now: this is the RD-7703, a rear derailleur for 7700-series front triple drivetrains.
With both pulleys at 13T, the Altegra and 105 triple derailleurs from the same era had 11T pulleys with an extremely long pulley cage, so my statement about Dura-Ace being the only one with this spec isn't wrong.
↑This is the RD-M953 SGS, a 9-speed XTUR rear derailleur.
SGS has a longer pulley cage than GS.
The largest low gear on MTB cassettes of this era is 34T.
34T is the same as Shimano 12-speed road component's maximum sprocket, but since this supports front triple and has 11T pulleys, I thought the pulley cage fundamentally couldn't be longer than this.
When I measured this XTUR rear derailleur's pulley bolt center distance with calipers, I got 86.6mm (all subsequent measurements are mine), and the final Rally measured 90.4mm.
By the way, this rear derailleur is what's called "low-normal."
Without the cable pulled, the chain doesn't rest on the top gear (smallest sprocket) but on the low gear (largest sprocket) — the normal specification is the RD-M952.
With low-normal, pulling the cable shifts toward the top gear.
The reason for this derailleur spec is that downshifting to low gear requires heavy cable pulling, but with low-normal the spring returns in that direction, so you can shift to low gear smoothly. That's why Shimano called low-normal "Rapid Rise."
The important thing to note is that with Rapid Rise, the shifter operation is reversed from normal.
With electronic groupsets, which are now standard, front shifting (to the outer gear) is forcibly driven by the motor, so it always works reliably. This means riders no longer need to consciously use pedal unweighting technique during front shifts, or worry that the chain won't go to the outer ring when it's on the top half of the cassette sprocket — technically sloppy shifting now works anyway. This isn't just "you don't need to think about it anymore since it shifts anyway" — the component wear differs between people who force it without understanding and those who do understand it, so knowing the mechanism is worthwhile.
What I want to discuss isn't criticism of that, but rather: "If there's a low-normal rear derailleur, wouldn't there also be an outer-normal front derailleur?"
If a front derailleur existed where the cage is positioned on the outer side without the cable pulled or tensioned, and pulling the cable shifts it to inner — then outer shifting could utilize the spring return, making it shift lightly.
↑Yes, here's an outer-normal front derailleur.
I'm bringing this up because I can actually show examples.
↑Suntour Sprinter.
↑Suntour SL.
True to its name, it was a lightweight front derailleur for the time, using aluminum (called light alloy back then) for the cage plates.
Unused stock. Being aluminum, any use at all results in chain scuff marks appearing immediately.
The pantograph shape is the same as the Sprinter.
The range adjustment screw is removed, but
Without the cable pulled (initial state), it's positioned on the outer gear,
and pulling the cable shifts it to the inner gear.
Now to get to the main point.
I recently assembled an R8100-series 12-speed groupset.
The previous R9100/R8000-series 11-speed groupsets had an issue where, due to the single-tension design, shifting to inner-small (inner times top) would cause chain sag — there would be no tension. This problem was so awkward that electronic groupsets were programmed to prevent shifting to inner-small.
So even if inner-small were somehow shifted to, the chain would sag yet the system wouldn't allow it — a "potential sag condition" that goes undetected (→here).
Few people use 12T top sprockets, so for most riders the third sprocket from the top is 13T. Single-tension rear derailleurs don't pull the cage back as far, making inner-13T very difficult for rear wheel removal. The 9100/8000-series rear derailleur has 11T pulleys top and bottom, but if you switch to aftermarket large pulleys, wheel removal gets even harder.
The 9200/8100-series rear derailleur also continues with 11T top and bottom pulleys. But since Dura-Ace now supports 11-34T, I wondered what they'd do about the inner-small shifting problem, and it turns out 12-speed electronic groupsets can now shift to inner-small.
They added a 54-40T crank option, so the chain length can handle 54×34T, yet they still need to ensure 40×11T doesn't sag with... 11T pulleys on a long cage. How would they manage that?
...by making a rear derailleur with abnormally long pulley cage spacing.
It's essentially equivalent to the GS (longer cage) version from the previous generation — just one length option for road derailleurs (SS is shorter, GS is longer pulley spacing).
The pulley bolt center distance of this RD-R8150 measured 99.6mm. That's longer than the final Rally.
The tension adjustment bolt range is also wider, but without cable installed and fully loosened, the rear derailleur pantograph sits so far back it would hit the frame.
Shimano's 12-speed MTB rear derailleur has 13T pulleys top and bottom, so I haven't measured it, but the cage doesn't look unnecessarily long. The cranksets come in single and double, with double being 38-28T only — not the 16T spread you get on road bikes — but the cassette goes 10-45T or 10-51T, so they'd need 13T pulleys or the cage would be absurdly long.
Shimano's 12-speed road rear derailleur is so long that if installed on a small-wheeled bike in a right-hand-traffic country, I'd worry about hitting the curb.
This is a separate matter — someone asked me to swap SS and GS on an 11-speed electronic Altegra RD-R8050. While disassembling the pulley cage, I measured the GS version's bolt center distance: 96.6mm. Shorter than the R8150 but already longer than the final Rally. This turned out to be longer even than the 9-speed MTB XTUR SGS, yet it's nominally called GS.
The same-generation Dura-Ace rear derailleur (RD-R9150) only came in SS spec, with a maximum low gear of 30T rather than 34T, so Altegra exceeded the final Rally's length first.
As usual, the front derailleur came with a ridiculous washer as part of the spec.
There's obviously very little contact area on this thing.
Especially with electronic groupsets, the motor forcing shifts creates massive stress on the frame mount, so this isn't good.
So I swapped it for the older washer design (→here).
Shimano's coated inner cables, adopted since the 7900 series, have excellent smoothness. With 7800-series and earlier components, they warned that brake and derailleur cables couldn't be properly secured, so don't use them (the image above shows proper matching). Yet despite being willing to tell such trivial lies, they won't fix the front derailleur washer degradation. Also, changing the brake inner cable securing bolt from 5mm to 4mm hex key is also stupid.
With coated cables, during shifting the cable moves back and forth around the outer stop area, causing the coating to come loose and peel. With frame-routed cables, if you try to pull out a frayed cable by drawing it into the frame, it gets stuck in the cable liner and causes problems.
You have to cut the inner cable and pull it back through the rear derailleur side. The image above is a brake cable, but shift cables develop the same condition.
Also, Shimano's STI levers since the 7900 series have sharp bends in the shift cable entry area. The steel strands directly below the end cap fray and snap individually (this isn't as common on Campagnolo Ergopower), and I suspect that non-coated cable might actually have longer lifespan here.
Actually, for 7900 and later components, I often assemble them with standard stainless cable instead of coated cable, but I don't just install it as-is. I make adjustments so the initial performance is lighter than simply slapping on a coated cable, and I also ensure that initial performance level is maintained longer.
That coated cable exists so people who can't properly assemble components can still get acceptable performance even doing it haphazardly. For me, it's just unnecessary meddling.
Also, as I mentioned, coated cables don't play well with frame-routed systems. But nowadays most frames are wired with designs that are essentially electronic-first, though they'll say "compatible with both mechanical and electronic — we'll just change the outer stop bracket so you can use mechanical if you insist." Campagnolo uses plain stainless cable as standard, though.
Initial performance (brake and shift lever lightness) and how long it's maintained with cable-actuated component parts varies greatly depending on the assembler's knowledge and skill. But switch to disc brakes and electronic shifting and those differences shrink substantially. Not "it's all the same regardless of who assembles it," but it gets close. Component makers certainly want to move in that direction, and with an oligopoly market bordering on single-supplier dominance, "What, you still using rim brakes and mechanical shifting?" style planned obsolescence comes easy.
Shimano's 12-speed electronic groupset has a lamp on the rear derailleur that changes color by mode.
The colors can be blue, yellow, green, or red, and the shift adjustment mode glows yellow.
Internally this appears to be a red and green mixture. The lamp on the rear derailleur shows yellow, but where that light hits the chain or cassette sprocket, it disperses into red and green light as shown in the image above.
I don't have the original vertical Rally, so I prepared a Nuovo Record from the same era.
Oops, my hand slipped.
The original Rally shares the same pantograph design as this Nuovo Record.
／：：：：：：：：：：：：：＼
＼：：：：：：：：：：：：：／
↑It looks like this — squares arranged like a clock face with Clous de Paris patterning, with the word RALLY written on top.
About vertical and horizontal derailleur designs.
When the frame mounting bolt and the pulley cage pivot bolt are roughly on the same axis, the pantograph orientation becomes vertical when mounted to the frame — that's vertical type. When the relationship between the frame mounting location and pantograph position forms an L-shape, causing the pantograph to become horizontal when mounted — that's horizontal type. Modern rear derailleurs are basically all horizontal type.
This rear derailleur is from the final generation Rally, the horizontal type version.
It doesn't say "Rally" anywhere, but the model name is definitely Rally.
Being a touring component, the pulley cage is extremely long.
I used to think that no road derailleur would ever exceed the pulley bolt spacing of this Rally.
The pulleys are white, so this is from the same era as C Record.
This white pulley is 10T, but even if a rear derailleur with a larger capacity rating existed, if it had larger-tooth pulleys, the pulley bolt spacing wouldn't necessarily be longer, so in terms of length competition, the 10T pulley final Rally has the advantage.
Some people occasionally say "Didn't Shimano realize the advantages of large pulleys?" but back in the 9-speed 7700 era, only Dura-Ace adopted large pulleys.
↑This one
The pulleys properly bear the Dura-Ace marking.
Before the real answer comes back, let me tell the truth now: this is the RD-7703, a rear derailleur for 7700-series front triple drivetrains.
With both pulleys at 13T, the Altegra and 105 triple derailleurs from the same era had 11T pulleys with an extremely long pulley cage, so my statement about Dura-Ace being the only one with this spec isn't wrong.
↑This is the RD-M953 SGS, a 9-speed XTUR rear derailleur.
SGS has a longer pulley cage than GS.
The largest low gear on MTB cassettes of this era is 34T.
34T is the same as Shimano 12-speed road component's maximum sprocket, but since this supports front triple and has 11T pulleys, I thought the pulley cage fundamentally couldn't be longer than this.
When I measured this XTUR rear derailleur's pulley bolt center distance with calipers, I got 86.6mm (all subsequent measurements are mine), and the final Rally measured 90.4mm.
By the way, this rear derailleur is what's called "low-normal."
Without the cable pulled, the chain doesn't rest on the top gear (smallest sprocket) but on the low gear (largest sprocket) — the normal specification is the RD-M952.
With low-normal, pulling the cable shifts toward the top gear.
The reason for this derailleur spec is that downshifting to low gear requires heavy cable pulling, but with low-normal the spring returns in that direction, so you can shift to low gear smoothly. That's why Shimano called low-normal "Rapid Rise."
The important thing to note is that with Rapid Rise, the shifter operation is reversed from normal.
With electronic groupsets, which are now standard, front shifting (to the outer gear) is forcibly driven by the motor, so it always works reliably. This means riders no longer need to consciously use pedal unweighting technique during front shifts, or worry that the chain won't go to the outer ring when it's on the top half of the cassette sprocket — technically sloppy shifting now works anyway. This isn't just "you don't need to think about it anymore since it shifts anyway" — the component wear differs between people who force it without understanding and those who do understand it, so knowing the mechanism is worthwhile.
What I want to discuss isn't criticism of that, but rather: "If there's a low-normal rear derailleur, wouldn't there also be an outer-normal front derailleur?"
If a front derailleur existed where the cage is positioned on the outer side without the cable pulled or tensioned, and pulling the cable shifts it to inner — then outer shifting could utilize the spring return, making it shift lightly.
↑Yes, here's an outer-normal front derailleur.
I'm bringing this up because I can actually show examples.
↑Suntour Sprinter.
↑Suntour SL.
True to its name, it was a lightweight front derailleur for the time, using aluminum (called light alloy back then) for the cage plates.
Unused stock. Being aluminum, any use at all results in chain scuff marks appearing immediately.
The pantograph shape is the same as the Sprinter.
The range adjustment screw is removed, but
Without the cable pulled (initial state), it's positioned on the outer gear,
and pulling the cable shifts it to the inner gear.
Now to get to the main point.
I recently assembled an R8100-series 12-speed groupset.
The previous R9100/R8000-series 11-speed groupsets had an issue where, due to the single-tension design, shifting to inner-small (inner times top) would cause chain sag — there would be no tension. This problem was so awkward that electronic groupsets were programmed to prevent shifting to inner-small.
So even if inner-small were somehow shifted to, the chain would sag yet the system wouldn't allow it — a "potential sag condition" that goes undetected (→here).
Few people use 12T top sprockets, so for most riders the third sprocket from the top is 13T. Single-tension rear derailleurs don't pull the cage back as far, making inner-13T very difficult for rear wheel removal. The 9100/8000-series rear derailleur has 11T pulleys top and bottom, but if you switch to aftermarket large pulleys, wheel removal gets even harder.
The 9200/8100-series rear derailleur also continues with 11T top and bottom pulleys. But since Dura-Ace now supports 11-34T, I wondered what they'd do about the inner-small shifting problem, and it turns out 12-speed electronic groupsets can now shift to inner-small.
They added a 54-40T crank option, so the chain length can handle 54×34T, yet they still need to ensure 40×11T doesn't sag with... 11T pulleys on a long cage. How would they manage that?
...by making a rear derailleur with abnormally long pulley cage spacing.
It's essentially equivalent to the GS (longer cage) version from the previous generation — just one length option for road derailleurs (SS is shorter, GS is longer pulley spacing).
The pulley bolt center distance of this RD-R8150 measured 99.6mm. That's longer than the final Rally.
The tension adjustment bolt range is also wider, but without cable installed and fully loosened, the rear derailleur pantograph sits so far back it would hit the frame.
Shimano's 12-speed MTB rear derailleur has 13T pulleys top and bottom, so I haven't measured it, but the cage doesn't look unnecessarily long. The cranksets come in single and double, with double being 38-28T only — not the 16T spread you get on road bikes — but the cassette goes 10-45T or 10-51T, so they'd need 13T pulleys or the cage would be absurdly long.
Shimano's 12-speed road rear derailleur is so long that if installed on a small-wheeled bike in a right-hand-traffic country, I'd worry about hitting the curb.
This is a separate matter — someone asked me to swap SS and GS on an 11-speed electronic Altegra RD-R8050. While disassembling the pulley cage, I measured the GS version's bolt center distance: 96.6mm. Shorter than the R8150 but already longer than the final Rally. This turned out to be longer even than the 9-speed MTB XTUR SGS, yet it's nominally called GS.
The same-generation Dura-Ace rear derailleur (RD-R9150) only came in SS spec, with a maximum low gear of 30T rather than 34T, so Altegra exceeded the final Rally's length first.
As usual, the front derailleur came with a ridiculous washer as part of the spec.
There's obviously very little contact area on this thing.
Especially with electronic groupsets, the motor forcing shifts creates massive stress on the frame mount, so this isn't good.
So I swapped it for the older washer design (→here).
Shimano's coated inner cables, adopted since the 7900 series, have excellent smoothness. With 7800-series and earlier components, they warned that brake and derailleur cables couldn't be properly secured, so don't use them (the image above shows proper matching). Yet despite being willing to tell such trivial lies, they won't fix the front derailleur washer degradation. Also, changing the brake inner cable securing bolt from 5mm to 4mm hex key is also stupid.
With coated cables, during shifting the cable moves back and forth around the outer stop area, causing the coating to come loose and peel. With frame-routed cables, if you try to pull out a frayed cable by drawing it into the frame, it gets stuck in the cable liner and causes problems.
You have to cut the inner cable and pull it back through the rear derailleur side. The image above is a brake cable, but shift cables develop the same condition.
Also, Shimano's STI levers since the 7900 series have sharp bends in the shift cable entry area. The steel strands directly below the end cap fray and snap individually (this isn't as common on Campagnolo Ergopower), and I suspect that non-coated cable might actually have longer lifespan here.
Actually, for 7900 and later components, I often assemble them with standard stainless cable instead of coated cable, but I don't just install it as-is. I make adjustments so the initial performance is lighter than simply slapping on a coated cable, and I also ensure that initial performance level is maintained longer.
That coated cable exists so people who can't properly assemble components can still get acceptable performance even doing it haphazardly. For me, it's just unnecessary meddling.
Also, as I mentioned, coated cables don't play well with frame-routed systems. But nowadays most frames are wired with designs that are essentially electronic-first, though they'll say "compatible with both mechanical and electronic — we'll just change the outer stop bracket so you can use mechanical if you insist." Campagnolo uses plain stainless cable as standard, though.
Initial performance (brake and shift lever lightness) and how long it's maintained with cable-actuated component parts varies greatly depending on the assembler's knowledge and skill. But switch to disc brakes and electronic shifting and those differences shrink substantially. Not "it's all the same regardless of who assembles it," but it gets close. Component makers certainly want to move in that direction, and with an oligopoly market bordering on single-supplier dominance, "What, you still using rim brakes and mechanical shifting?" style planned obsolescence comes easy.
Shimano's 12-speed electronic groupset has a lamp on the rear derailleur that changes color by mode.
The colors can be blue, yellow, green, or red, and the shift adjustment mode glows yellow.
Internally this appears to be a red and green mixture. The lamp on the rear derailleur shows yellow, but where that light hits the chain or cassette sprocket, it disperses into red and green light as shown in the image above.