Hi, when i have my bike in highest gear (big chainring fron smallest at back) and even second highest there is some chain rub on the derailleur. Do i need to adjust the limit screws or adjust tension to sort this?
If it used to work and now doesn't, and you haven't played with the limit screws, then it's the cable tension. A test for this is to grab the derailleur and try to pull it further over. If it moves further, then it's not being stopped by the limit screw. If you can't move it further, then back off the limit screw slightly until you can.
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