Hello. I have a Pacific Tucson 18 Speed Mountain Bike. I bought it a couple years ago with the intent to ride. I rode a couple times for no more than an hour total and then put it up. My fiance and I are now starting to ride bikes. We went out once for about an hour and the shifter on my bike broke on the inside because it is cheap plastic. I know that it is not a great bike since I got it from the local Meijer Store, but I didn't have the money at the time for anything else, and I don't have the money now to get something better. My question is: Is it possible to buy an good aftermarket shifter to put on it to correct it's problems? It is easily out of warranty to have the company fix it. I actually like the bike a lot. I just wish they didn't skimp and use cheap plastic in the shifter. Any help would be greatly appreciated!