Flight Deck with 6700 ultegra RD not shifting 10 gears

[liamb]

Hi All

I have just replaced all my Cables and fitted a new Shimano RD-6700 Ultegra SS Rear Derailleur to my bike. The Rear Derailleur is replacing a 105 RD. The Brake Shifter set up is a 105 Flight Deck. For some reason I can only shift through 8 gears not 10 I cant get the 2 largest gears on the cassette. Without the cable connected I cant manually move the RD to the 2 largest gears and it returns to the smallest gear without shifting past that point. The new RD looks different to the original, the cage is 10mm longer than the 105 RD. The RD has 6700 on it as does the box. Do I need to make my chain longer?? Any ideas??

Cheers

Bill

[MichaelB]

Maybe the limit adjusters are not set right ? Without the chain, ensure that you can manually move it to all 10 gears.

The cage may be longer, as 6700 (and 5700 and 7900) were changed to have a 33T overall capacity and 28T rear max (prev version as 31T and 27T)

[liamb]

good suggestion Michael. I had tried to but not luck initially but after a few more goes there was a clunk and it moved. I now have full movement but as the Derailleur gets up to the 3 largest gears the shifter can barely move and the cable is piano string tight. It also takes 2 to 3 clicks to get the Derailleur moving.?? from the smallest gear. I think its time to revisit YouTube and start from scratch. Never thought something this simple woulfd be so difficult

[MichaelB]

good suggestion Michael. I had tried to but not luck initially but after a few more goes there was a clunk and it moved. I now have full movement but as the Derailleur gets up to the 3 largest gears the shifter can barely move and the cable is piano string tight. It also takes 2 to 3 clicks to get the Derailleur moving.?? from the smallest gear. I think its time to revisit YouTube and start from scratch. Never thought something this simple woulfd be so difficult

Sounds like starting point isn't quite right re cable position.

At least you are getting closer !!!