Newbie here, I bought a bike this year. I've been riding a lot and my bike is going to need tires soon. It has 700x23c and I'm definitely going to move up to 25 but I was also thinking about 28. I'm 54 yrs old, 6'0" and weigh 240 lbs. I'm looking to smooth out the bumps, maybe getting a little extra tire mileage. I don't care about rolling resistance, I need to lose 20 pounds before I start caring about that. But I don't want the bike to have the rolling resistance of a comfort bike. After riding this new bike, 9 speed 105 with 700x23 tires and seeing how smooth, effortless, and fast it rolls, I now think by 35 year old 10 speed Schwinn has too much rolling resistance with it's 27"x 1 1/4" tires. Would the 28 have the same rolling resistance that the 27x 1 1/4" tire have? Is there much of a difference between 25 and 28? I don't want to be huffing and puffing using the 28 nor do I want to cut back the distance that I ride.

The first thing to do is to figure out whether a 28 will fit in your frame. The next thing is to find a higher quality 28, as many dealers tend to sell only lower end tires in that size and up. The reason your Schwinn rolls badly is partly the clunky tires and partly the clunky wheels. A good 28 mm tire will roll fine.

A good 28 mm tire will roll fine.

True... in fact it will roll better than a 23mm that has the same casing and tread.

Check out the Continental Ultra 2000, 700x28, decent tire, decent price.

http://rivbike.com/html/parts_rollypolly.html

sweet riding tire. made in a 3 part mold so they have a really round profile. they roll into corners like a dream, almost a tubular feel. highly recommended.