
I need new gears on a Mongoose mountain bike. It’s about 13 years old. Just wondering if anyone knows about what it would cost to get new gears or fix the gears. Wondering if I should just buy a new bike instead.
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It very much depends on what quality you want, and how extensive the work. I would guess anywhere from about $100 for minor work to $7-800 for upgrading the drive train with good quality components.
I suggest you take the bike to a bike store and ask for recommendations. Then you can decide.
It would cost more than the bike is worth.
Just get a new bike, as the previous answerer said some decent gears would probably cost more the bike is worth.