I recently received a second-hand wind speed of 700, and the dial on the back is not very easy to use. Do you want to replace it? Is the model number shimano RD-TY 18?

The model is this one, which was originally equipped with SIS screw. There are also hook-type ones, but that kind of back dialing has basically been eliminated now. You can't install a hook on this car.

A little better than this is Tourney TX50 series. If you want to upgrade, you can buy a Shimano 7-speed rotating flywheel and a 7-speed Shimano A050 manual dial. Just change these two things to upgrade the speed from 18 to 2 1. There is no need to replace the chain because 6-speed and 7-speed chains are common, but if your chain has been cut, you may need to replace it.

No matter how good it is, it is not necessary for this car. It's a road imitation, not a real road car. Commuting is ok, and it is more convenient to have shelves and mud removal.

Don't worry about being laughed at. People who really like cars don't laugh at novices. They're all novices. After all, no one is born to know cars. Read more and you will understand that this thing is actually very simple.