Shift cable housing bend
 

Update I'm a dummy, this being my first offroad bike, seems some dirt and mud has got into the cable making it a bit dirty, some lube and all is well now. Down the road i'll look into some sealed housing and cutting some length to cover the exposed cable sections.

I've been having some issues with the shifting on this bike, its always jumping around, and i'm starting to think that maybe the bend in the cable housing is too tight. When I shift into a smaller cog, the cable releases a bit from the shifter, but the derailleur isn't moving down.

https://i.imgur.com/cm6qJsJ.jpg

I have the screws set fine, and the cable tension is good on shifting into low gear, but going down to high its really poor shifting. Sometimes it takes two shift clicks for the cable to losen up enough to where it will shift.
Wanted to get some opinions before I take it all apart to run a new cable and housing.

bias towards low gears can be caused by:
too much cable tension
derailer hangar bent inwards
pick one

A common issue I see with this seat stay path for rear shift cables is that the casing loop gets filled with water/grit/grime (rust) as the water runs down the length of the exposed cable and enters the confines of the casing. New cable and casing loop can often help. The length of the casing loop looks to be within normal curvature. Andy.

My first thought too was 'cable and housing'. Squirt some light oil (or even WD40 though it's not a lubricant) in there and see what happens. If it frees things up, buy a new cable and housing.

It wouldn't hurt to get your lbs to check that the hanger isn't bent. Sure, you're supposed to be able to see it but I've found that's not always the case and it's best checked using the purpose made tool.

Just looking at your photo, I wouldn't have thought the housing had too tight a bend, but I'm happy to be corrected on that.

Yup, turns out it was the cable was just dirty from some cross racing.

This is my first time owning a cross bike and i've been riding it pretty hard compared all my other bikes which have been road only. I guess i'll just have to keep an eye on lubing the cables every now and then. The cable/housing is only 4 months old, but I guess being exposed is allowing dirt to get in there. ( though they are cheap cables and housing ) I guess i'll keep an eye out for sales for some nice jagwire kits.

Read Sheldon's notes on preparation of the rear derailleur loop: https://www.sheldonbrown.com/cables.html#cutting Using his technique may be helpful in getting a smooth-running system.

Looks OK to me. have bike shop check derailleur hanger alignment..






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updated, see first post.