Toward end of thursdays razz out i notice my chain catching something every half turn?.. Sounds like fouling front mech.. So move it a tad with me thumb on shifter but still does it under power -on middle ring & last couple gears on rear.. .. Turns out the pins on the big ring seem to be catching the chain on every half turn of crank???.. Why!!?? Have filed em down a bit but a random occurance none the less…. U had this???

Is the chainline good? What chainring is it? I had a Turbine top ring and whilst in middle ring, as the chain left the ring (at the bottom) it was catching the pins on the top ring. Could NOT stop it , checked/changed chainline etc, fitted a blackspire ring , same size, and was fine!

Dan running slx rings not worn out ,obviously chain is moving out of straight a bit when on smaller cogs on the cassette but never normally have this issue..?.. Possibly file a tad more ofc the ofending pins #gofindfile

Used 0.6mm chainring spacing washers on mine to give a little more clearance, will still catch on the outer two sprockets, but I only use those when in the big ring anyway.

Coatesy cheers,ye i like to keep chainline straight so on big ring by time get to last 2 gears on cassette… But may swap big ring for a new (bigger) one!!.. Just to top up my top end speed on a few warpspeed summer segments #crestarun #defendingpreciouskoms ;))