Ultegre 10 speed - noisey when on 3rd largest sprocket

[bjammin]

When riding on the 3rd largest sprocket & small front sprocket (19-39), there is a constant but small 'gear not alingning up noise', it is minor but anoying, all other gears are good. Complete bike was purchased 1 year ago and has done this from day one. Chain is on correct way, every thing else is clean and in order. I've noticed that the 3 largest sprockets are in a group of three? is it spacing issues? Anyone else heard this about Ultegre 10 speeds?

[macca33]

Chain could need a bit of oil, sprocket may be worn / damaged. Hard to say and it is odd that it is that sprocket alone causing the grief.

cheers

[scirocco]

Can you get rid of it by adjusting the barrel adjustors slightly? Sometimes the gears may be just a touch out of adjustment and it shows up first on one particular ring. Just try adjusting a quarter of a turn at a time, keep track of how many times you turned it and you can always put it back to where it was if it upsets the other gears.

[bjammin]

yes i could get it better using barrel adjusters, unfortunately this is the trade off for getting it perfect. My nine speed was fine, i guess 10 speeds are more fussy

[antipodean]

Check that the chain is central as it comes off the lower derailleur pulley, a slightly bent hanger can cause the side plate of the chain to catch on the pulley momentarily, creating noise.

[jules21]

it is possible to have a piece of dirt under the cable housing that snags at the same position (i.e. when you select 3rd cog). try cleaning out the cable/housing or replacing.