ronin4740

Today I learned that an Ultegra RD-6870-SS Short Cage Derailleur is firmware locked to not allow the configuration of an 11-32 cassette in the eTube software... So even though you can replace the jockey wheel cage with the GS version with a few turns of the wrench you can't program the darned thing correctly...

Grr...

Oh well, was a fun exercise in calculating chain length, swapping parts (the stupid screw that keeps the cage from rotating back too far would NOT budge on the new inner GS cage part - I had to dremel a slot in it to get enough torque on it to move it) and ultimately cursing the Gods in the heavens...!

Guess I'll just go order a RD-8050-GS and call it a day.

Cyclist0108

I never told my Di2 derailleurs about my 11-36 cassette or my 46/30T crank. Yet it works fine.

That B-screw needs (needed) a JIS #2 screwdriver, or go buy a new bolt with an allen key head for $0.89 at the hardware store.

colnago62

I use a 32 on my 9000 without a problem. If you plan on using the 32 in semi full sync mode, you have to use the custom to set up the cassette, or not. I could never tell th difference.

ronin4740

Okay. If you guys think it's okay to leave it setup this way with a 52/36 front chain ring set I guess I just won't worry about it then... Was a little worried as on the way up the cassette the sync mode doesn't shift to the little chain ring until the up shift to the 32T rear gear... and I can't seem to program it to shift down one cassette gear sooner for some reason... Looks like I ought to pick up a few JIS screw drivers as well. The hex bolt is a good idea as well.

Cyclist0108

Mine is programmed to mimic how non-electronic shifting works, so the gearing doesn't matter.

However, I have to ask why you would modify the rear derailleur, rather than simply get a smaller set of chain-rings.

ronin4740

The cost of the 11-32 cassette and the gs cage parts was less than the cost of a smaller ultegra chainring set.

Also now I have a spare 11-28 cassette if I decide to buy a tacx smart trainer for off season...

jadocs

That's fine if you do not use synchro shift. If someone uses synchro shift the rings and cassette matter because it uses the ratios to calculate where you need to be optimally.

colnago62

There is a custom mode where you can manually set the parameters for where the derailleurs shift. It is a pita figuring out the gearing, but once you do, just save it and you are good.

jadocs

That's correct, so far setting the correct (default) ratios has been working great for me.

TimothyH

What exactly is locked out? Is 11-32 not an option in E-Tube when it detects a 6870 short cage? Sincerely asking. Not trying to challenge.

The RX805 clutch derailleurs will cause the two smallest sprockets to be locked out when the front is in the small ring. You will not be able to use your small front ring with the 11 or 13 tooth sprockets in the rear. It just won't shift into those combinations.

The RX805 also eliminated manual mode. It is semi-sync or sync only. The workaround is to set the front to shift zero times when the rear is shifted - effectively the same as manual mode.

I don't know if the 8050 behaves the same as the RX805 but keep it in mind as you do the setup.


-Tim-

ronin4740

11-32 isn't an option when etube sees a short cage derailleur. 11-28 is the largest selection.

I'd also like it to shift down to the little chain ring from the big chain ring when going from the third largest to second largest cassette gear but I can't seem to configure it to do this.

More fiddling, video watching and maybe a shimano support call are in my future.

cthenn

This is making my eyes water a little bit, but are you saying you can override the setting where the synchro is forced to shift? My synchro shift going to a lower gear is not where I'd like it to be, but I can't seem to program the gear combo where the synchro shift happens. IE-I have a 50/34 and a 12x28 on the back, the synchro shift going down gear is the next shift after 50-25(second cog), whereas I want it to synchro shift at 50-23(3rd cog). I like the upshift end just fine, so I don't want to alter that to "fix" the other side of the synchro shift.

Long story short, is there a way to override etube settings to set the synchro wherever I want? And if so, does that affect actual shifting performance?

Sy Reene

hmm.. is it worth waiting for Di3?

Badger6

Yes, and I think so.

You can set the cog where the front chain ring shift is triggered in S1 mode, for both up and down...and how many cogs it moves in relationship to the front chain ring shift. Google the procedure, it's explained for every permutation of the eTube software. I'll let an experienced mechanic answer with the science, but it strikes me that shifting the front works better at certain points on the cog as opposed to others, and experimentation, in my experience, is useless on a stand, you need to be on the pedals (at least I did).

For a video explaining the programming using the desktop software:

Seattle Forrest

I've been thinking about going back to this.

cthenn

LOL, duh, didn't even think to Google/YT this...I just got caught up reading and posted my question. Thanks, I'll check this out!

ronin4740

The video is great but he never shows moving the top down in blue on the left side. That's what I haven't been able to figure out how to do. In my configuration I'd want that blue highlight to be on 2.17 instead of 2.00 to avoid the top jockey wheel from getting pulled in really close to the big gear in the rear cassette while the bike syncro shifts...

Maybe I'll ask the bike shop when I pick it up today.

Badger6

Hmmm. I adjusted mine using the iOS app, and I was able to move each box. If I recall, however, at certain times some of them are locked from moving, I just don't recall the instances that did that in the app. What I do know is that I was able to fully adjust everything. Ask your shop, the Shimano software/apps are not always as intuitive as you'd think.

ronin4740

Ya... I'm going to wish I'd brought the USB adapter with me. The shop may have one though. I can at least show him what I'm talking about in the Android app.

Guess I could download the iOS app to my iPad as well.