Bicycle Mechanics - Help with tire/wheel/tube problem.

I got my old nishiki out after 20 years and am running it single speed. Problem is I am extremely new to maintaining bikes. I cannot seem to keep the rear tube from getting damaged.

First tube got a small pin size hole on the inside part of the tube (not sure if i am describing it correctly). The 2nd tube seems to have been damaged badly near the stem and it won't even inflate at all after sitting for a few days.

I thought I'd start with the basics since I do not know what I am doing.

Wheel is an Alex Rims R450 6061H-T6 622x14. No idea about the brand, never heard of it, just what the shop happened to have at the time.

Tire is a Continental Ultra Sport 23-622 (700x23c). Again just bought what the store had and said would work.

2nd tube is a Slime 700x 19-25 presta.

Does anyone think there might be a problem with the tire/wheel/tube combo I am using?

The rubber strip that goes between the inside of the wheel and tube is in place. The tire is not inflated in the pic. I run the PSI between 100-120 per whats written on the tire.

Thanks for the help!

Sounds like you have things pretty well covered. The tire/wheel/tube combo should work fine.

The culprit for the pinhole on the inner part of the tube may be the rubber strip. Adhesive-backed cloth rim strip/tape works best--it doesn't shift around and expose any sharp edges on the rim. Speaking of which, you ought to inspect the rim for burrs and the like.

The only time I ever damaged a tube at the stem was when I screwed on the presta nut too tight. It pulled on the stem so much that it weakened the surrounding rubber and popped. Just tighten it after it's been inflated to just barely snug. That area can also be damaged if the stem comes out of the rim at an angle--point it straight to the hub. And, again, check for sharp edges near the valve hole.

thanks sir!