Big 5 does not repair bikes, I would recommend Good Karma bikes.
I don't believe big 5 does bike repairs.
I don't work at Big 5 store but what I've can recommend is; you should look for the brand name of your bike; search in the internet once you find it; you can ask them if they carry the parts you need;order it! When u order it they should have the instruction how to install that part you need/or you should go back to your bike original purchased booklet it should have the instruction to assemble the parts you need it. Hopefully you keep your original brochure. You can also goggle it maybe they will be able to help. Good Luck. Hopefully my feedback help you!
Big 5 doesn't have a bike servicing department there just into the sales of bicycles
Thanks! Your answer is awaiting moderation.