Yeah this sounds really natural. It would usually be said by a salesperson / someone selling a bike. "I can sort you out" means "I can help you, I can give you what you need." (a bike)

HI Nadia, This is grammatically incorrect statement, but it can be understood. It is what is described as "americanism".... a slang language that is made popular by American TV and movies. Although I am a fan of American movies, their English is not always the best instructor. The correct statement should read: If you are needing a new bike, I can assist you. I hope this helps you.