linuxelf

So, my road bike has 2500 miles on it, and I finally got my first flat. Looking at the tire (a Vittoria Zaffiro), it was showing signs of wear, so I just had the tire and tube both replaced. The new tire is a Kenda Kwest (the only tire the bike shop had.) I didn't think anything of it. Took the bike out for a ride, and 6 miles in, the tire was flat. Took it back and they replaced the tube for free. 25 miles later, flat. Took it back and they took the wheel strip off, checking it for anything that could be poking the tire. They said the hole was in the outside of the tube, so they checked the tire for anything that could have poked through, and found nothing. They replaced the tube.

It was then that I noticed that this tire is only rated for 85PSI and I've been running it at 110, just like my old Vittoria. So, I figure that must be the problem. I took it out for another ride yesterday at 85PSI. Hated the ride. It just felt sluggish, but I got my 30 miles in without getting a flat.

I go to look at the bike this afternoon, and the tire is flat again. I have to believe it's something with this cheap tire, so I'm headed to a different bike shop tomorrow to find a better tire.

My old Vittoria ran 2500 miles, and was probably still ok (not perfect, but probably better than this Kenda piece of junk.) I'm currently riding on 700x28c tires, and was thinking of moving to 700x23c. I'm assuming that a 700x23c tire will fit a wheel that was formerly running a 700x28c, correct? Anything else I need to keep in mind when changing to this tire? Any tire recommendations? Any problem running a 700x23c on the back and a 700x28c on the front? (I'd rather not change the front tire until it needs changing)

Currently, I'm leaning towards the Vittoria just because I was very pleased with the last one I had, but I'm fairly new to cycling. I've only been at it about a year.

*edited for readability*