Nah I think you'll be ok. Looking at mine I think it's there to make it quieter if your chain is rubbing. I think re indexing the gears should be ok. I do have a 5800 front mech spare if you wanted to buy one if it doesn't work. It's a clamp on but I can't see why you couldn't swap the plastic bit over. Looks pretty simple.
Nah I think you'll be ok. Looking at mine I think it's there to make it quieter if your chain is rubbing. I think re indexing the gears should be ok. I do have a 5800 front mech spare if you wanted to buy one if it doesn't work. It's a clamp on but I can't see why you couldn't swap the plastic bit over. Looks pretty simple.
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