My son has a 24" mountain bike that's 1 month old. Today, the wheels went "dead" suddenly. they rotate fine but when he pedals, there is no power to the pedals at all. The chain tension is fine - I see no missing parts or pulled out cables. What could this be?
Some advice you said 1 month old, see if you can take it back to the place where you purchased it.
Good maintenance to your Bike, can make it like the wheels are, true and smooth!
It sounds like the freewheel hub in the rear wheel has broken.
Take it back to the shop where you bought it from and get it exchanged for a new bike.
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