Shimano 11 speed question

[Doncantador]

Any one knows if it's compatible to use Ultegra DI2 that runs on 10 speedvto work on 11 speed cassette?

 

[alienator]

Any one knows if it's compatible to use Ultegra DI2 that runs on 10 speedvto work on 11 speed cassette?

There are quite a few folks wondering if there will be a firmware upgrade that allows as much or if someone will come up with a hack that allows as much. So far there's nothing available to allow a 10spd Di2 RD to work with 11spd

 

[alfeng]

Originally Posted by Doncantador .

Any one knows if it's compatible to use Ultegra DI2 that runs on 10 speedvto work on 11 speed cassette?

Of course, alienator is probably correct that a firmware upgrade (if available) may be necessary ...

But, because my probably-faulty recollection is that the Cog spacing may-or-may-not be the same on 10t & 11t Shimano Cassettes AND because there may be a certain level of stupidity (vs. "artificial intelligence") in the electronics, you may only have to change the stops on the rear derailleur if the motor stepping rate will continue beyond the existing width of a 10-speed Shimano Cassette ...

So, if you must know before the official announcement, then try this ...

• remove the chain from your bike ...
• reset the LOW stop so that the derailleur will theoretically move inboard by about another [COLOR= rgb(0, 0, 255)]4[/COLOR]mm (N.B. of course, if you do this test then you will need to correct this later BEFORE using your drivetrain with a wheel which has a 10-speed Cassette!!) ...
• put an unlaced hub (why take a chance of smashing the derailleur into any spokes?!?) + a 10-speed Shimano Cassette in your frame ...
• see whether or not the cage moves beyond the 10th cog to where the 11th cog would theoretically be ...

OR, you can borrow a CAMPAGNOLO rear wheel with an 11-speed Cassette to see if the derailleur will step from the smallest to the largest cog (of course, that will be AFTER you change your DI2 rear derailleur's stops) ...

• for YOUR reference, here is a eyes-on comparison of an 11-speed Campagnolo Cassette (on the left) with an 11-speed Shimano Cassette (on the right) ... the difference appears to be less than 1mm to me, but you may feel that it is more than 1mm (which it maybe) ...

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• if the Di2 rear derailleur can negotiate a broader span than the 37.2mm of a 10-speed Shimano Cassette AND/OR can negotiate the 40.1mm span of a Campagnolo 11-speed Cassette then you'll probably be good-to-go (!?!) after you buy the new 11-speed compatible hub-or-wheel & Cassette ...
• OR, if not, then not ...
• and then, you'll have to wait to see whether-or-not Shimano's bean counters allow for the alluded to firmware update

BTW. I love Shimano, but if YOU really thought that you every wanted-or-needed 11-speeds with an electronic drivetrain then you probably should have ponied up for Campagnolo EPS drivetrain the first time around ...

• of course, being the infidel that I am, if I were to use an 11-speed Campagnolo EPS setup then I would probably end up trying to use an 11-speed Shimano (accept no substitutes!?!) Cassette because I would want the larger Cogs which the Campagnolo Cassettes just don't have ... OR, I would re-stack the Campagnolo Cassette with a sufficiently wussy bailout Cog.