I was changing gears on my bike in late 2021 and the chain came off the inner ring and ground into the frame of my bike. It made a huge mess of the carbon:

Taking the bike frame to a carbon specialist and repairing this cost me $1,000. Then, I bought a whole new drive train: chain, rear cassette and front rings - costing a further $500. $1,500 is a massive investment - I justify these big services on the bike by comparing them to train fares - that's 50 weeks of train trips.

So anyway, it happened again on Friday morning. Exactly the same thing: I changed gears, the chain has come off the inner ring and ground into the frame of my bike. It has made another (admittedley smaller) mess of the carbon in my frame.

So, I took the bike to the shop. They are unwilling to do anything about this situation. 'Not our fault, our work is good - the gears and chain are obviously working fine and we don't have this problem with anyone else. It's your fault'. They best he's willing to do is give me parts at cost for the repair, once I spend another $1,000ish getting the frame repaired again.

I wasn't blaming the bike shop, I was blaming the design of the bike. But they don't think they can bring Trek into this.

I don't know what to do about this. I really like my bike usually, but spending $3,000 on it over 2 years, only to have a 6-year-old bike at the end of it was never on the cards. I doubt I'd even get $1,500 for it if I tried to sell it. I'd almost be better off giving the bike away as-is and putting that $1,500 toward a new bike. Probably not a Trek this time. I feel like I have the bike equivalant of a write-off.