I have an older Schwinn Le Tour road bike and I have been getting a lot of flats recently. I just bought new Continental 700x23 Gatorskin tires, but am still having problems with flats; my tubes are fairly new too. Even with full pressure, I somehow manage to get a flat. They are typically pinch flats, but not always.

I am thinking of getting wider tires/tubes-- how do I know if my bike can handle the extra width? Will I just have to adjust my brakes? Also, how much would a flat sealant or tire liner help? My bike is used primarily for commuting.

Thanks!

Do you have good floor pump with a guage and pump them up before every ride?

Pinch flats are almost always the result of under-inflation and/or tires that are too narrow for the load or road conditions. While narrow tires are the in thing you have to maintain some perspective.

Look at the automotive world. Small sports cars get small tires, bigger SUV's use bigger tires and Trucks use bigger yet. Same with bikes - bigger loads require bigger section tires.

I don't know what you weigh but you might look here for a guide to choosing tire width and pressure based on your weight. IMO, you want tires that are fine at less than 95psi or so.

Also I suspect that your 23mm tires are too narrow for your rims, which were probably originally fitted with wider tires.

A properly fitted tire will be roughly 1-1/2 times the width of the rim and assume an Omega shaped cross section. Overly narrow tires stand up like an inverted U and lack the flex room in sidewalls giving a harsher ride and are more prone to pinch flats. Here's a guide you might use (scroll down to the chart) for matching appropriate tires and rims.

Overall commuting usually calls for wider tires than you might use for sport riding. You're riding in heavier traffic, usually on lousier pavement, and have less room to maneuver around road hazards like potholes, and sewer grates. If you replace your tires go for something with a 28-35mm section and you'll find yourself far better off going forward.

To answer the rest of your questions. You're rims can probably handle wider tires as shown on the chart I referenced earlier. You don't need to adjust the brakes for different tires, they should only touch the rims and the tires have no effect. Tire sealant might help if you continue to get flats, but you may not need it after addressing the of your pinch flats.

Schwalbe Marathon Plus are a much heavier tire , but all the extra weight
is in the tread,
a puncture barrier lays beneath the tread, to like tire liners,
but outside, so glass, has some gummy stuff to penetrate,
before cutting casing and tube.

and also.. with (Gloved) hand you can knock out the glass,etc.
right after you see that you may have passed thru it.

And pay attention to road debris, steering around it ,
works well..

proper pressure,depending on road surface but heres an" oldie " BABY POWDER ,talcum allows tire and tube to flex as apposed to sticking.If a puncture occurs tube is easily removed.TIP carry alcohol prep pads to clean tube prior to instant patches.Always carry PPS,pump,patches,spare tube.Check your glue,murphys law dries glue!

I'm around 200lbs in riding gear and maybe a touch more with a pack of goodies on my back. I commuted over "average" roads for years and have yet to get a pinch flat on any of my road bikes. And I ran a couple of sets of 23's but mostly 25's over the years.

So I really have to wonder two things. A- are you ensuring that your tires are aired up to within about 10 to 15% of the rated max pressure before each ride. B-How do you ride? Do you sit up and stand on the pedals when about to hit some rough patches or do you remain seated solidly on the saddle? Do you tend to ride around areas of bad potholes or are they unavoidable? If you ride onto or off of curbs do you just "hit" them or do you try to stand up and lift the bars as the front clears and then lean onto the bars to ease the rear up or down? Are the roads in your area truly awful with lots of big and deep potholes?

Pinch flatting is totally avoidable. But it's also totally NOT due to the tires or tubes. Switching brands and types won't help much other than going to a fatter tire size which is properly aired up at a lower pressure. But if you let THOSE tires get down to around 50% of their rated pressure you'll find yourself pinch flatting even those.

So perhaps it's not your tires which need changing but your pressure checking and riding style. Or if the roads are truly so bad that they are more correctly labeled as "non-roads" then perhaps a switch to some cyclocross or heavy load touring tires is needed.

I prefer liners over slime, I don't like slime (messy) and liners seem to work well. Are you getting flats from road debris or pinch, etc? The type of flat might dictate your solution. I.e. if you're getting pinches, might be riding style and pressure. If debris, you might want to look at liners (I've seen mountain bike guys make "ghetto" liners by simply wrapping inside of the tire with duct tape. It's just enough to keep out goatheads.

Another thought is the route you take. My ancedote: I used to take a 10-mile route that had much road debris and I was getting flats regularly. I switched to a more maintained road (same bike, tires, tubes) and never got a flat again.

Summarizing others and adding too, Reduce Flats by:

1. Riding a quality tire
2. Correctly sized
3. With good tread
3. Properly inflated

Options:
1. Tire Liners
2. Thorn resistant tubes
3. Slime

Changes in habit, recognize what causes your flats:

1. Route Selection
2. Obstacle Avoidance (curbs, potholes etc...)