Sergievsky
I just turned my bike into a 1x, Tanpan/XTR rd with 105hydro shifters, 42t front / 11-45 back. And with the hills where I ride (& the sorry shape I’m in) I think the gear spread is just fine.

I’d like to upgrade, but I’m not sure if the new Ultegra RX can clear the 45 cog. I’ve read one post somewhere where he tried it I think with an 11-46, but with a wolftooth DM roadlink, but haven’t seen any others.

I’ve thought about a Force 1 setup, but have read several reviews about disc brake rub on the hydros, & I absolutely despise that noise! I wouldn’t mind cable discs like the Klamper or Spyre, but I have never tried them. Always used Shimano hydros & have been satisfied with it.
Anyway, any experiences/advise would be much appreciated.
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fb40dash5
I have neither an RX800 nor a 45t cog. But I do have an R8000 on a 40t, and it juuuuuuuuust clears that. I mean, I guess you could maybe get a little more going nuts with the B-tension (I've only got the original one about a turn from maxed) but it's already waaaaaay far from the 11t. Mine shifts OK so far (only got maybe 5-600 miles on any of it) but is a little finicky shifting in the 3 tallest cogs.

Maybe you could clear it with a Roadlink as well, but I'd think it would shift like poo with that + the Shadow hanger... could be wrong I guess.
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Sergievsky
Ah I see thanks. Do you have yours set up as 1x or 2x? I saw in uTube they made it work at 40t at 2x. I haven't ruled out going back to 2x, but due to my hubs I would need to make it work with the 40t largest cog.
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fb40dash5
1x here as well, 42t front, not that it should matter aside from cage capacity.

Curious question... since you have the XTR/Tanpan combo doing what you want it to do, and I'm assuming this XTR is new enough to have a clutch, what exactly is an upgrade about the RX800 besides ditching the Tanpan? Don't get me wrong, I bought my R8000 and limited myself to a 40t (and so far it works for me) because I didn't want a cable travel modifier, but if I needed more than that to climb, I'd be using the same kinda setup you have.
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Sergievsky
Actually, the setup surprisingly works good. I have no idea about longterm though, with that cable modifier, I don't know if the efficiency will change. I thought about changing because on my previous setup it didn't work well at all, probably because I had a sram 10-42 cog, plus it was 2x. It was a good thing I had a shimano freehub on my mountainbike that I could switch over to the XD on my my gravel (Onyx hubs), so I that's how I got to try it out. 

I actually put back the 10-42 after it worked well with the 11-45 thinking I could shrink my front chainring and it was the 2x that screwed everything up, but even at 1x the tanpanXTR didn't shift well at all with the 10-42...so back went the shimano freehub 11-45.

I'd like to upgrade my shifters to Ultegra level now, and thought maybe if the new Ultegra Rd will work then I can get rid of the tanpan, but I guess it really isn't an immediate need and maybe I'm expecting a degradation in performance of the tanpan that will never happen.


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pamountainbiker
I have the Ultegra RX rear derailleur on my Ibis Hakka. I've run it since June so have a fair amount of real world experience with it. It's being run with an XTR 11-40 cassette and I can reasonably say that it will most likely NOT clear a 45T cog. Every bike is different, on the Hakka I run the B screw in halfway, it has no problem clearing the 40T, the issue is shift degradation on the other end. The farther in the b screw the less shift accuracy in the small cogs and most of my riding is doing in the first 5 cogs of the XTR cassette (I run a 42T chainring). I'd rather have better shift accuracy in higher gears than lower. Setting up the RX to run on a 45 could be done with a RoadLink but shift performance would probably be bad. As it is now, mine shifts very well across the cassette, even though I very occasionally have some cog to jockey pulley rub (intentionally due to how I set the b screw) when going up to the 40T. I could eliminate this but at the detriment of shift accuracy elsewhere on the cassette. One other thing to note, an Ultegra 8000 rear derailleur to my eye has slightly different geometry from the RX.
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dangle

pamountainbiker wrote:
Setting up the RX to run on a 45 could be done with a RoadLink but shift performance would probably be bad.


You made some excellent points, but this is the one I'm curious about. I haven't had an RX in hand and I don't have a cassette with anything bigger than a 42 to try it, but...

Any evidence the Roadlink would make it shift worse? I feel like the b screw is mostly moving the guide pulley up and away from the cassette which affects those small cogs more. The chain doesn't have as much time to be 'guided' by the guide pulley when it's pulled up and back. The Roadlinks (I would guess that you are aware of this) keep the guide pulley lower (relative to the cassette) for a little bit better cassette/chain wrap. What I had found was that I could get an 11-34 to work okay with a standard 11 speed Shimano rear derailleur with the b screw pretty jammed in there to clear the 34, but the Roadlink (and backed out b screw) shifted noticeably better on the rest of the cassette. Possibly due to better chain wrap and the guide pulley getting to do it's job a little earlier in the rotation?

Anyhow, I *wonder* if that n=1 experience could be extrapolated for a larger cassette and larger capacity rear derailleur. Trying to fit a 45 (Modified via Wolf Tooth?) cog in a 1x road application does seem a bit screwball, but I'm all for people trying to figure out what works for them. Maybe the relatively inexpensive Roadlink could be the ticket? I would be curious to find out!

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Bike John
The XT derailleur already has the necessary chainwrap for a 45T, has the original clutch design that the RX copied, and is cheaper besides. It just leaves you to solve the road shifter cable pull difference with the Tanpan (assuming you weren’t running Di2).

I’m curious, if anyone has tried both solutions on the same bike, whether the difference in shifting was noticeable one way or the other...
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Sergievsky
I might give it a go then. I’ve already wasted enough money switching cogs & derailleurs & tanpans...why not waste some more on another derailleur & roadlink? 😬 I could even switch back the XD driver & try out the 10-42 if it doesn’t clear the 45t. (tho I read on wolftooth’s site it’ll improve shifting but not up to factory levels...whatever that means). Thanks for all your input so far, and any more coming!
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mogwaiboi
I have the Tanpan with a 2 x 36/46 front and XT rear der. with 40T cassette.  I find that it shifts quite well when the cable tension is dialled in, but for me the tension goes out of whack at least every few weeks which is quite annoying.  I want to swap to the Ultegra RX / Roadlink to keep the clutch as I like to use the bike on rough terrain sometimes.
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Sergievsky
That's a big reason I haven't switched to the Force, the Ultegra RX will still leave me that option to go back to 2x. But I think I'd have to change rings to the same 46/36 front. 
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nublar
I have the RX800 with 11-36 in the back. Clears it with the B screw 1/4 the way in. Pretty sure I can get 11-42 with more B screw and a longer chain. 
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ITry2Hide
Anyone try the force 1 with the e- thirteen 9x46? I’ve heard the long cage will work. Oh well, I’ll know on Tuesday. Building out my new Hakka MX.
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Sergievsky
ITry2Hide wrote:
Anyone try the force 1 with the e- thirteen 9x46? I’ve heard the long cage will work. Oh well, I’ll know on Tuesday. Building out my new Hakka MX.


I asked the question in Jenson (if it'll work with larger than 42), and the reply I got was "i'm using it with a 42t and the b- screw is all the way in."

BTW, I decided to just close my eyes and pay up and worry about it later, and went with a Dura-Ace Di2 & XTRdi2 RD...didn't want to risk any more money and have it not work as good as I want.
Anyway, this setup is....AWESOME![thumb][cool][biggrin]
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ljsmith
ITry2Hide wrote:
Anyone try the force 1 with the e- thirteen 9x46? I’ve heard the long cage will work. Oh well, I’ll know on Tuesday. Building out my new Hakka MX.


I have used the Force 1 with the e13. It works with no issues. However I found the jumps in the e13 to be too big, so I no longer use it, it’s better suited to mountain biking.
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