I recently started to have a problem where the chain randomly goes from the large front gear to the smaller one.
Ive been trying to work out the reason for this and would like some input on the more likely culprit:
- The front derailleur is somehow slipping. in order for it to stay in the position for the large gear there is quite a bit of tension on it. (Its a 105 shimano if it makes any difference)
- My front cassette is worn out AND i noticed that the chain angles towards the left as it comes off the front cassette so it naturally wants to slip down to the smaller gear.