SRAM experts needed: "X-Actuation" vs "Exact Actuation" / Srampagnolo

Hey there!

Need some advice from the SRAM experts.

"Exact Actuation" and "X Actuation" are always different from cable pull, right?

Already build some 10s Srampagnolo bikes, but now I want to have a sprocket greater than 36 in the rear.

Does such a rear derailleur exist?

• Exact Actuation
  
• 2xX
  
• 10 or 11s
  
• biggest sprocket 40/42
  
  

Other question: is Srampagnolo possible with X-Actuation?

Thanks in advance....

the 10 speed gx?

The 10s GX Type 2.1 is what I'm currently running...specified up to 36. Does this work in cases up to 40 or 42?

I use exactly this RD on my city bike with an 11-42 - works well, but wouldn't want to have a bigger cassette. Mine's 1x though, mind.

Ah, nice to hear. That would be the best, need to check if it works also in terms of chain length with 44:28.

And just to make sure: you're running the type 2.1 10s, not type 3 11s?

can't say for sure if that'll work, but the limiting factor on my system is definitely not the overall capacity of the rd.
nope, definitely a 10 speed version (iirc, the 11 speed mtb rds aren't compatible)

Cool...I will give this a try....thx for the hint!

But for the record it would be still quite nice to understand the differences between the two terms (X vs Exact). So if still anyone could comment on that...

Exact Actuation (Road 10 & 11sp, MTB 10sp and below) = 3.1mm of cable pull with each shift
X Actuation (MTB 11sp and up) = 3.48mm of cable pull with each shift

Ah, thanks for the explanation.

I was puzzled, because I was missing Exakt Actuation for MTB 11spd and thought if I had overlooked something - but then it is like that (unfortunately).

@Eeyorecore Can you explain how Exact Actuation (Road 10 & 11sp, MTB 10sp and below) = 3.1mm of cable pull with each shift?
If the pull ratio of the Exact Actuation is 1:1 then the amount of cable pull from one shift on any 10 speed SRAM shifter has to be more than one shift on an 11 speed shifter. So, the amount of cable being pulled by the different speed shifters is not the same. That would be my understanding and that is why you can use any Exact Actuation rear derailleur with different speed shifters, because it's the actual shifter which is varying the amount of cable being pulled.
AJ

The different amount of cable pull I cited is for 11 speed derailleurs. It’s the only point of “overlap” between the two versions.

IIRC the neither Exact nor X are exactly 1:1 and X Actuation ratio is different across generations.

Thanks for the reply, but am I right in thinking, regarding Exact Actuation only, that the same rear dérailleurs can be used between 10 and 11 speed SRAM shifters because the distance the mech moves for each speed is determined only by the shifter? The 10 speed shifter will pull more cable per click than the 11 speed shifter? All Exact Actuation rear dérailleurs will move a distance in direct proportion to the length of cable which is pulled by the relevant shifter, and this is why the Exact Actuation mechs are interchangeable between different speed shifters?

All Exact Actuation rear dérailleurs will move a distance in direct proportion to the length of cable which is pulled by the relevant shifter, and this is why the Exact Actuation mechs are interchangeable between different speed shifters?

Yes. The derailleur is blind when it comes to speeds, all that matters is it has the same pull ratio as the shifter

Yes, derailleurs are agnostic to shifters as long as the ratio is the same. so Sram 2:1 (Rocket, Attack, MRX, etc) work with Shimano 2:1 ratios, basically anything before 10 speed mtb and 11 speed road.

Sram ESP and later Exact Actuation are 1:1 ratio and similarly cross compatible across generations as long as it’s 1:1.

Sram X actuation have different ratios across 11 and 12 speed and are only compatible within their own eco system.

Shimano 10 and 11 speed and up are their own can of worms.