Chain skip on 5th sprocket
I noticed today that there's some chain slippage when the gear is on the 5th (7 gears) sprocket. It happens every so often when I am hard on the pedal. It's a lousy feeling when I am climbing a hill too to have the pedal skip. It is also a sprocket that I use quite often in combination with my 2 largest chainrings.
Any help will be appreciated.