Originally Posted by
kyle70b
I am a bike moron. I just bought a bike today that says Shimano-equipped. It has a Shimano Tourney SIS ( Shimano TZ) and has a 7-Speed Index. Everytime I rest my feet from pedalling, the chain makes a noise and loosen up from the sprocket. I don't know what the heck is happening with the bike. Will somebody help me with my ignorance and tell me what to do to enjoy my daily afternoon bike exercise. Much appreciation for your help.
It sounds like you have a freewheel problem, whereby the freewheel is trying to drive the chain when you coast. Freewheels are so inexpensive that it's not worth the effort for most novices to buy the tools to take them apart for repair.
However, before you buy a replacement freewheel, there is one simple repair that may fix the problem. Remove the wheel and lay it on it's side, freewheel facing up. Dribble some light oil around the outer edge of the freewheel cover plate, while spinning the cogs backwards. The oil should seep into the freewheel and may free up the movement. Alternately, some members first dribble solvent to free things up, then dribble oil, to lubricate the internals. If you have the tool to remove the freewheel first, it does make things easier and much neater, but it's not mandatory.