# Change Dura Ace RD 9070 Short cage.



## mejepa

Hi:

I'll purchase 9070 group set but I'd like to use the Ultegra 11-32 Cassete. I know that it's not possible out of the box.

I'm looking for some info from a Shimano expert that can confirm me that if I purchase this three part numbers
* Y5X998040 – Outer plate & plate stopper pin (GS-Type)
* Y5VG09300 – Iner plate (GS-Type)
* Y5V598140 – Pulley Bolt 12.5 mm (2 pcs) for GS-Type
I will get what I’m looking for; use the Dura Ace with a 32 gear. Other question is where to buy this material, but this will be after we agree that the change will work.
I have taken the info from here:
http://techdocs.shimano.com/media/t.../RD/EV-RD-9070-3442_v1_m56577569830818665.pdf
http://techdocs.shimano.com/media/t...RD/EV-RD-6700-2919A_v1_m56577569830753764.pdf
You can compare that the interface between the cage and the RD body is the same. It’s true that it seems that the distance between the “Stopper pin” and the axle of the upper wheel is a bit different but I think that this is not important.
Regards and thanks for reading.


----------



## rcb78

Sounds like you're talking about taking the cage/pulley assembly from a GS derailleur and moving it to the rd-9000 right? It only 'kinda' works. In addition to the pulleys being located slightly lower in the cage relative to the derailleur body, the angle the body travels at is different too, meaning the actual bodies are different.
I did this for a customer recently (after warning him it may not work) and it helped, but was still not enough to clear the 32t without a little pulley noise even with a longer b-tension screw installed. We tried an unmodified re-6800-gs and it worked.
Ultimately though it will vary from frame to frame. My CX bike that has a 6800-ss derailleur installed could easily clear a 34t and maybe a 36t cassette if I wanted to. Other frames barely clear the advertised limit.
My advice would be to mount the ss derailleur you have now and see how much clearance you have with an 11-28 installed. Then try to visualize if a 32t cog would fit. Changing the cage/pulley assembly along will only buy you another 5mm or so.
Almost forgot, I don't know where you can buy this stuff separately. My customer bought a second derailleur and we robbed the parts from it for the attempt.


----------



## mejepa

rcb78 said:


> Sounds like you're talking about taking the cage/pulley assembly from a GS derailleur and moving it to the rd-9000 right?


Thanks a lot for your answer.
Yes, specifically I want to take the cage/pulley from a mechanical RD6800GS and use it to change the Di2 RD9070SS one. Similar to what you have already done.


rcb78 said:


> It only 'kinda' works. In addition to the pulleys being located slightly lower in the cage relative to the derailleur body, the angle the body travels at is different too, meaning the actual bodies are different.
> I did this for a customer recently (after warning him it may not work) and it helped, but was still not enough to clear the 32t without a little pulley noise even with a longer b-tension screw installed. We tried an unmodified re-6800-gs and it worked.


Did you have any issue wit this spring when you unscrewed the bolt?









What I mean is if this spring is pretensioned. If I dissassemble it will I have problems to reassemble?



rcb78 said:


> ultimately though, it will vary from frame to frame. My CX bike that has a 6800-ss derailleur installed could easily clear a 34t and maybe a 36t cassette if I wanted to. Other frames barely clear the advertised limit.


Mine, if things don’t go wrong, will be a 2014 Cannondale Synapse.


rcb78 said:


> My advice would be to mount the ss derailleur you have now and see how much clearance you have with an 11-28 installed. Then try to visualize if a 32t cog would fit. Changing the cage/pulley assembly along will only buy you another 5mm or so.


Thanks. Really I will use the 32 gear from time to time. On summer, when I go to climb the “Col Larrau” (LARRAU*-*Altimetrías de Puertos de Montaña)



rcb78 said:


> Almost forgot, I don't know where you can buy this stuff separately. My customer bought a second derailleur and we robbed the parts from it for the attempt.


Yes this is an option I suppose more expensive and if it doesn't work ...
I'd like to do this but in a cheap way. This Yumeya cage is made of carbon and it's very expensive.


----------



## rcb78

The spring you're talking about in the pic above is under tension (torsion), but it's not enough to fly apart when released. It's pretty easy to put back together too, just hook the spring, wind it into position and wiggle the plate back down. Have the c-clip handy and it'll pop together pretty easily.
Like I said, try it It might work for you because every frame/derailleur hanger combo is different. Some will work, some won't. The frame that didn't work was a Cervelo R5.


----------



## spdntrxi

wondering if you completed or tried this project.. I'm wanting to do the same, maybe with a mid cage from a 6800 on the 9070.


----------



## mejepa

Not yet.
I receive my Cannondale Synapse, last week and I do not purchased the Dura Ace di2, yet.

Regards.


----------



## spdntrxi

cool... I'll update if I get to it first. Going to build a Trek Madone 6.2 WSD for the wife... she prefers to have a 32T. If shimano would come out with an ultegra cassette with 30T in 11s, I would assume the 9070 RD would be fine with no "hack" needed, current 28T is not going to cut it though.


----------



## robbyville

spdntrxi said:


> cool... I'll update if I get to it first. Going to build a Trek Madone 6.2 WSD for the wife... she prefers to have a 32T. If shimano would come out with an ultegra cassette with 30T in 11s, I would assume the 9070 RD would be fine with no "hack" needed, current 28T is not going to cut it though.


Hi there, wondering if you had gotten to this yet? I'm right on the verge of deciding if it's worth it. My frame is a Domane 5 series so clearance would most probably be the same as your wife's Madone (they share the same derailleur hanger I believe).


----------



## spdntrxi

I'm pressed for time so I went with the 11-28 ... The amount of really steep hills she will.actually do is limited.

I will eventually get a tiagra 30t .. Derivet it and remove one of the single cogs for the cassette add the 11s spacer and give it a try..


----------



## robbyville

spdntrxi said:


> I'm pressed for time so I went with the 11-28 ... The amount of really steep hills she will.actually do is limited.
> 
> I will eventually get a tiagra 30t .. Derivet it and remove one of the single cogs for the cassette add the 11s spacer and give it a try..


Gotcha thanks for the response! I have the 28t and feel like it's everything I've needed last year and this. Still there was a 5.5 mile climb yesterday with over 10% average some sections up to 19% and a fondo I do each year where I have to stop briefly to get my heart rate down, thinking that I should give this a go. Hoping to find someone who has documented how they did it and with what level of success (I don't want to compromise shift quality)


----------



## spdntrxi

robbyville said:


> Gotcha thanks for the response! I have the 28t and feel like it's everything I've needed last year and this. Still there was a 5.5 mile climb yesterday with over 10% average some sections up to 19% and a fondo I do each year where I have to stop briefly to get my heart rate down, thinking that I should give this a go. Hoping to find someone who has documented how they did it and with what level of success (I don't want to compromise shift quality)


that's kind of were I am at too.. I'm waiting on 9070 cranks from stages and everything else is ready to go. I will eventually try to 30T option... but I want to try the whole system first and know how the shift quality is before I start to hack at things. I did chinz and get an ultegra cassette.


----------



## robbyville

spdntrxi said:


> that's kind of were I am at too.. I'm waiting on 9070 cranks from stages and everything else is ready to go. I will eventually try to 30T option... but I want to try the whole system first and know how the shift quality is before I start to hack at things. I did chinz and get an ultegra cassette.



Well I know you mentioned a Madone so I thought I would let you know that my experience did not work out for me. The retro fit of the GS Cage to the 9070 derailleur was fine enough but when installed I couldn't get into the last couple of gear (strange since it goes 32-28 and I had been using a 28). Put the b-screw out all the way, still no go. Reversed the B-screw so that the head was on the underside on the perch but ultimately the angle required got so extreme that the screw would slip off the perch and mess up. Went to the hardware store to get more screws, different lengths and head types, even goofed around with the idea of a nut and washer on the underside to build up against the derailleur hanger perch all to no avail. Simply the wrong angle. Realized that for the rides where I absolutely need the 32 I could easily enough swap out derailleurs so I ordered a 6870GS and will give that a try. My frame is a Domane which I believe uses the same hanger as your wife's Madone.

To make matters worse, in all the messing around I somehow screwed up the threads on the B-axle assembly (where the b-screw threads in), so when I put the short cage back on the 9070 and tried to re-install I had messed myself over. I installed one of my "Magyver" b-screws (long screw, nut then into the stripped hole, then another nut) so that I can screw it down or up using the nuts as my threads. yeesh!

Called Shimano to get a new B-Axle assembly, out of stock, no ETA, same for a bunch of distributors but found one on Ebay from Australia. Oh well live and learn, at least I can still ride until I replace the assembly!


----------



## MMsRepBike

As a Shimano tech. the official advice is to use a 6870 RD with your 6800 11-32 cassette on your otherwise 9070 system.


----------



## spdntrxi

MMsRepBike said:


> As a Shimano tech. the official advice is to use a 6870 RD with your 6800 11-32 cassette on your otherwise 9070 system.


can I say I don't like that answer


----------



## robbyville

MMsRepBike said:


> As a Shimano tech. the official advice is to use a 6870 RD with your 6800 11-32 cassette on your otherwise 9070 system.


Yeah I hear you, but I REALLY enjoy the 9070, I know the ultegra works just as well but I am and have always been a Dura Ace fanboy so was really hoping to make a cool hack job work and maintain appearances. Bi know my concern is driven by pure snobbery. Plus I just received the 6870 GS, it's very nice but one chunky monkey compared to the 9070!

I'm going to install it over the next couple of days for some riding I have planned. Probably not smart to swap derailleurs regularly not sure how that might affect chain strength. I'm going to order the new B-axle assembly so that I can get the 9070 back to spec and think about if there is any other way I can get the hack to work.


----------



## MMsRepBike

robbyville said:


> Yeah I hear you, but I REALLY enjoy the 9070, I know the ultegra works just as well but I am and have always been a Dura Ace fanboy so was really hoping to make a cool hack job work and maintain appearances. Bi know my concern is driven by pure snobbery. Plus I just received the 6870 GS, it's very nice but one chunky monkey compared to the 9070!
> 
> I'm going to install it over the next couple of days for some riding I have planned. Probably not smart to swap derailleurs regularly not sure how that might affect chain strength. I'm going to order the new B-axle assembly so that I can get the 9070 back to spec and think about if there is any other way I can get the hack to work.


Well to be honest as soon as you put that 11-32 Ultegra cassette on there you "bastardized" the DA system. Not having the titanium cogs showing and instead having a big fat granny gear cassette on there pretty much ruins it. Having the Ultegra RD wouldn't then really look out of place. Some might argue that the cassette is more visable and distinguishable than the finish on the RD is.

As far as swapping RD's, don't cut your chain every time you do it, that's just abusing your chain. Instead just remove than replace the jockey wheels on the RD.

There are ways to get it to work, the pros do it. There's a lot of pros on DA running compact cranks and 11-32 Ultegra cassettes. Most of them stick with the DA RD and run an aftermarket cage setup. K-Edge I think might make one, another few companies do. They do get it to work. The SS and GS do not function the same though, they do not follow the same path over the cogs so it really is a hack no matter how you look at it. It's just a matter of getting the hack to work in an acceptable manner. 

For the record I live in the mountains and myself use a compact 11-32 setup so no hate at all. Most everyone I know around here uses the same setup. We're all on Ultegra RDs because it's easy and perfect. Nothing against hacking the DA, it's just not easy or necessarily very effective.


----------



## Matador-IV

Hmm, I run DA short cage with an SRAM 11-32 cassette. I change from 11-23 to 11-32 without adjusting, shortening or replacing anything. 

I must be doing something wrong


----------



## robbyville

Matador-IV said:


> Hmm, I run DA short cage with an SRAM 11-32 cassette. I change from 11-23 to 11-32 without adjusting, shortening or replacing anything.
> 
> I must be doing something wrong


9070?


----------



## robbyville

MMsRepBike said:


> Well to be honest as soon as you put that 11-32 Ultegra cassette on there you "bastardized" the DA system. Not having the titanium cogs showing and instead having a big fat granny gear cassette on there pretty much ruins it. Having the Ultegra RD wouldn't then really look out of place. Some might argue that the cassette is more visable and distinguishable than the finish on the RD is.
> 
> As far as swapping RD's, don't cut your chain every time you do it, that's just abusing your chain. Instead just remove than replace the jockey wheels on the RD.
> 
> There are ways to get it to work, the pros do it. There's a lot of pros on DA running compact cranks and 11-32 Ultegra cassettes. Most of them stick with the DA RD and run an aftermarket cage setup. K-Edge I think might make one, another few companies do. They do get it to work. The SS and GS do not function the same though, they do not follow the same path over the cogs so it really is a hack no matter how you look at it. It's just a matter of getting the hack to work in an acceptable manner.
> 
> For the record I live in the mountains and myself use a compact 11-32 setup so no hate at all. Most everyone I know around here uses the same setup. We're all on Ultegra RDs because it's easy and perfect. Nothing against hacking the DA, it's just not easy or necessarily very effective.


Agreed


----------



## spdntrxi

Matador-IV said:


> Hmm, I run DA short cage with an SRAM 11-32 cassette. I change from 11-23 to 11-32 without adjusting, shortening or replacing anything.
> 
> I must be doing something wrong


right or wrong you give me hope...


----------



## NealH

Matador-IV said:


> Hmm, I run DA short cage with an SRAM 11-32 cassette. I change from 11-23 to 11-32 without adjusting, shortening or replacing anything.
> 
> I must be doing something wrong



No, it just means your particular bike has a longer derailleur hanger.


----------



## robbyville

Matador-IV said:


> Hmm, I run DA short cage with an SRAM 11-32 cassette. I change from 11-23 to 11-32 without adjusting, shortening or replacing anything.
> 
> I must be doing something wrong


What frame and derailleur are you running?


----------



## cave dweller

The standard Shimano specification for the Di2 RD-9070 is a 33 tooth capacity (difference in front + difference in rear).

I have pushed the RD-9070 SS to 35 tooth capacity running a 52/38 front and 11/32 rear. You can't push it any further then this with the short cage.

The derailleur clears the 32 tooth cog without a problem, it is on a Giant TCR ISP. 

I have seen one modification to a Di2 9070 using the Yumeya cage. It was apparently not a direct fit and required spacers and a bit of stuffing around.

I am very interested to know if the Ultegra GS cage is a direct fit as I need to stretch the tooth capacity out to 37 teeth for some serious climbing events coming up.


----------



## spdntrxi

cave dweller said:


> The standard Shimano specification for the Di2 RD-9070 is a 33 tooth capacity (difference in front + difference in rear).
> 
> I have pushed the RD-9070 SS to 35 tooth capacity running a 52/38 front and 11/32 rear. You can't push it any further then this with the short cage.
> 
> The derailleur clears the 32 tooth cog without a problem, it is on a Giant TCR ISP.
> 
> I have seen one modification to a Di2 9070 using the Yumeya cage. It was apparently not a direct fit and required spacers and a bit of stuffing around.
> 
> I am very interested to know if the Ultegra GS cage is a direct fit as I need to stretch the tooth capacity out to 37 teeth for some serious climbing events coming up.


I've run 50-34 with 11-32 with the 9070 SS on one of my wheels, I stay away from big-big combo but it seems to work the few times I have tried.


----------

