9000 rear der setup

[Kingfisher]

Fine tuning a used 9000 rear deraillur. Upshifts (going towards hub) are fast and crisp, but downshifts seem to lag a bit and not as sharp. Is there a mechanic trick I can use to correct? Cassette is 6800 ultegra.
Thanks

[Wayne77]

Sounds like friction in the cable housing...either worn cables, or a bend somewhere with a tight radius.

[Dead Man]

Originally Posted by Wayne77

Sounds like friction in the cable housing...either worn cables, or a bend somewhere with a tight radius.

Yup. You using the polymer coated cables? You can clean and loob and see if that fixes it (as well as check for pinching at the cut ends of housing/kinks in housing) but I have been finding that once things get laggy it's just best to recable - new housing, new cables.

Lil trick I learned from old potato years ago - to isolate the source of the lag, if you have externally routed bike, pluck the cable at the down tube, and if it's snappier up shifting that way, you know the problem is in the front somewhere.. if it's still laggy, you know the problem is in the back.

[oldpotatoe]

Originally Posted by Kingfisher

Fine tuning a used 9000 rear deraillur. Upshifts (going towards hub) are fast and crisp, but downshifts seem to lag a bit and not as sharp. Is there a mechanic trick I can use to correct? Cassette is 6800 ultegra.
Thanks

Long enough der housing, trimmed well. I use a wee bit of Boeshield in the housing. Clean and smooth under BB guide. Sometimes 5mm der housing at the rear der. Metal(brass) ferrules, not the plastic crap.

[EricEstlund]

Make sure your hoods are fully seated as well.