woodrow5

Well, I have done many researches for upgrading. I bought 6603 10spd Shifters, Sram 10spd cassette, 10 spd chain. However it doesn't work with 10spd XT M780 Rear Derailleur.

With proper wire cable installation; I still couldn't shift the RD to last two biggest teeth sprockets. I have searched couple post and people said Ultegra 6603 doesn't work with any RD with Dyna Sys...

Do you guys have any solution ?

Thanks!

jnbrown

I think any XT 9 speed derailleur such as M770 would work.

himespau 

Yeah, 10 spd mtb derailleurs (dyna sys) don't play nice with anything not dyna sys. Don't know why they'd do it that way, but you'll need 9 speed rd's to work with road components.

Team Fab

From a Thread I started a couple weeks ago.

I asked a local tandem shop and this is what they sent me.

I think it works for 6603 as well.

I just ordered XTR 9 speed and 6703.

"Sorry for the delay, but I wanted to check for opinions with our suppliers and Co-Motion Cycles, who use the Ultegra shifters on many tandems. They use the 6703 model, which is the one currently supplied, with the 9-speed XT rear derailleur (M772). The overall width of the 10-speed cassette is the same as the 9-speed, and the M772 actually has a greater chain take-up than the newer 10-speed one. The reason for this is that Shimano designed the new 10-speed drivetrains to use only 2 chainrings, so there is not as much chain length change as with 3 chainrings, especially when tandems often use such a wide range of gears.

Hope this helps.

We can get you the levers, cassette, rear derailleur and chain if you wish. The levers list at $670, but we will sell them for $569. The XT rear derailleur lists for $161, but for you, $131, giving a total of $700 plus tax. If you wish to add a chain, they run from $45 to $75, and cassettes can be had from $50 (Tiagra 12-30) to $70 (Deore) $94 (SLX) to $125 (XT). The mountain 10-speed cassettes all start with 11 teeth."

vrooom3440

How did this XT RD-M772 9 speed work out with 10 speed cassette and 10 speed road shifters?

FWIW the 11-32 is used with the 105 brifters and a 105 RD on Co-Motion's Pimera. They do run the medium cage version rather than the more typical road short cage 105. From their spec sheets it would appear that they run a similar setup with Ultegra RD on higher level bikes.

It appears that 11-32 to 11-34 however is the dividing line on how big you can go with the road RD's. I tried the same setup XT RD-M780 as the original poster here and hit the same darn problem of not being able to swing it into the two biggest cogs.

twocicle

Previous to installing Di2 on our tandem, we used a Shimano RD-M970 with an otherwise all Ultegra 6703 10spd drivetrain. Technically the M970 is a 9spd RD, but as others have indicated, these have the same throw ratio as "10spd" designated RDs. The M970 is also "Low-Normal" which means the spring pulls toward the smaller cogs (typical for your purpose).

The M970 is probably far more "zoot" (and costly) than most people need, but it does have a few advantages... stiff carbon cage, super light weight, capacity for any cassette / chainring combo, looks great. Here's a photo of it installed previously on our 10spd equipped tandem:

Bostic

What is the current non break the bank model that can be bought brand new Shimano Mountain Derailleur that will work with 10 speed 6703? Looking online I've found the RD-M591 that doesn't have the word "shadow" in it. The 105 model 5701L is also priced about the same as the Deore M591 but has a shorter cage.

Currently I have the B Screw reversed on the 6703 Mid Cage derailleur with a 10 speed 11-32 XT cassette on our Cannondale. I also have the chain sized one link shorter than ideal to pull the top pulley a bit more away from the 32t when in 30x32.

twocicle

"Shadow" models are fine (preferred in fact), it's the "Dyna-Sys" models you want to avoid. Shadow is a design that tucks up nicely to avoid obstacles and eliminates chain slap, plus the derailleur cable loop is shortened (see photo in post #6 above) as that is a fixed point which does not rotate.

With the RD-6703 (or any other model) you can improve top pulley clearance by replacing the default 11T pulley with a 10T pulley. Economically speaking, this is the cheapest changeout. I have in fact done this to my UDi2 RD and using the 6700A GS mid-length cage. If I could find a compatible long cage from another Shimano RD, I'd use that instead.

ct-vt-trekker

I'm using the Shimano Deore M591 on 2 bikes one has Ultegra 6603 triple shifters the other 105 5603 triple and they work great. Shifts as well as Ultegra derraileurs, no issues whatsoever. The M591 comes in black or silver and can be bought online for about $40.
This is a long cage derraileur mostly used on touring bikes so it can shift a 34 tooth cassette.


I just noticed that the original OP posted over 2 years ago, I'm he's got a solution by now!!

vrooom3440

I called up Co-Motion to see what they use on the Java...

Looking at their spec sheets I noted their other bikes with 11-32 rear run either 105 mid-cage or Ultegra mid-cage. The Java with an 11-34 rear just says "XT", but the official word was RD-M771 which is a 9 speed version of the XT. If you are swapping from a 105 or Ultegra as I was this is the most direct swap since it is pre-Shadow and used a looped derailleur cable mounting as do the road bike setups.

You may find RD-M771 hard to get (obsolete, only sold online) in which case you can step up to the slightly more current RD-M772 9 speed XT derailleur. You will need to shorten up your rear derailleur cable a bit to make this one work but it does make for a very clean look. And I found it works perfectly with the 10 speed brifters and 10 speed XT 11-34 cassette.

Now if I can just get the front derailleur to work as perfectly...

dwmckee

Great reference info!