Ridinmurray

I've had a complete Ultegra group for about 9 months or 2500 miles. Last 600 to 700 miles the rear derailuer has not been shifting correctly up to the larger sprockets. It will shift from the larger sprockets down the cone ok, but not up the cone well all the time. Sometime I will shift & it will not go up, then I shift again & it goes up 2 rings?
My bike shop has adjusted several times with no success. I've have friends having same problem with same product. I've heard Shimano has an issue with these models, any input is appreciated.
I've changed cables, no difference.

Wordbiker

It could be a defective or worn out shifter.

The good news is just about every manufacturer warrantees parts for a full year. If the group was installed as an aftermarket upgrade, you still may have some recourse directly through Shimano.

FBinNY 

I doubt it's the shifter, but rather the less expensive issue of cable friction because of dirt or a worn liner, a trim adjustment, a bent hanger, or the "B" screw setting.

Do a quick test of the RDs shift response shifting by pulling the bare wire away from the down tube like a bow string. It should be smooth and free as you run it up and down through the gears. If the RD motion is at all jerky, the rear housing loop is the likely culprit.

If the action is smooth shifting from the downtube, try adjusting the cable a bit tighter. This should improve the shift to larger sprockets though at the expense of more sluggish shifting in the other direction. If you can get all the shifts up to larger sprockets to work well but it hangs on the return, try plucking the cable at the downtube. That pulls down a bit of cable that may be hung up in the HB to frame housing section. If Plucking works, you need to lube or replace the housing.

Also check the height of the RD on each sprocket. There should always be daylight between the upper pulley and sprocket with about 1" of chain free between them. Watch as you shift to the next geat larger, if the RD seems to stutter or get pushed back, it's too high. Tighten the "B" screw to push it lower and things should improve.

All the above assumes a straight hanger. If you can't spot a cause of your headaches, have this checked and eliminated before wasting any more time.

Ridinmurray

Hanger checks OK. Cable routing is internal so pulling it manually would be difficult but, I'll try something.
Cables are new Jaguar, I just changed them. Same results.
Thanks for your response I'll check the other stuff.

FBinNY 

Something changed, and only you know the sequence. Did the problem begin before you replaced the cables of after? Any other possible changes? Did the issue come on suddenly, slowly over a short time, or very slowly over a long time getting worse until you decided to deal with it.

Since it used to work, then stopped, the clue is to figure out why, or what changed.

Since you have internal routing the bowsting option is out, so try to shift the lever slowly feeling for smoothness of the cable run, and watching that the RD is moving likewise in one smooth motion. Also check the RD height.

Lastly, understand that as chains wear they develop more side flex. That means that more overshift is needed to get the chain to move. Usually this is more of an issue on the smaller sprockets, but if the RD is a bit high may be a factor in your situation. Take a moment to measure your chain for stretch (wear) using a 12" ruler, and if it's near the replacement point anyway, see if a new chain solves the problem. Don't toss the old one in case it doesn't make a difference, in which case you can put it back now, or when the new chain matches it's current wear age.

Wordbiker

OK, a little more detail:

Shift up to the largest cog in the rear, stop the wheel, then shift all the way down without pedaling. This will release some slack in the cable. If there are any split stops at all this will allow you to remove the ferrule from them for even more slack. Grab the inner wire with your fingers and slide it manually through the housing. Does it feel sticky or buttery smooth? If sticky there's still friction inside and lubing may take care of it. If not, then replace. If it's smooth it could be your shifter.

You'll get all sorts of advice on how to free up a sticky shifter, but my method is to use a graphite lock lube available at most hardware stores. With the small straw provided, spray it inside the shifter mechanism until it is liberally dripping out the bottom. The solvent wipes out the gunk and when dry, the graphite lubes things up again and frees up the tiny pawls. It may take a few applications, but it's worked wonders for me.

In my dry environment I also use a non-aerosol version of the same product for lubing the cables (the thin consistency wicks inside very nicely and is not sticky when dry) and all of the derailleur pivots.

achoo

One other thing: when's the last time the chain was cleaned and lubed?

Ridinmurray

Chain does need cleaning. I may try the graphite lube, then make my adjustment.
Thanks.

embankmentlb

Check the cassette for tightness.