I have been thinking about moving up in tire size for quite some time. Tired of flats and feeling every little grain of sand on my 700x25 equipped trek 1200.

Everything I read regarding tire limitations seems to reference frame/fork clearance. I think I can go to a 32 without any issues in this regard, but, my 25s rub on the stock integra side pulls even when they are released. I think I could jam a 28 through, but, not a 32.

Is there a way to adjust the brakes so they release far enough to accept a fully inflated 32? I was gonna go with a 28, but I keep seeing pics of what appear to be road bikes with 32s parked along unpaved trails. Not gonna do any single tracking on the trek, but we do have an old rail line bike path that I'd be comfortable riding with 32s.

What I probably ought to do is set up my old 520 for this duty. It's cantilever brakes would take a motorcycle tire!

Probably either cyclocross or maybe touring bikes, not road bikes.

That's one of the reasons why most touring, sport-touring and cross bikes use cantilever, long-reach or disc brakes. The largest tires you can probably use with your frame are 28s, but those should be a big improvement over your 25s. You can still buy some pretty lightweight 28s (eg, Conti GP 4 Seasons) but I haven't seen any light 32s.

I just put some 700x28's on my Univega Sportour and they fit fine without fenders. The sidepull brakes on this one have release levers to allow the arms to open up enough to slip an inflated tire between the pads.

Check if your bike has a brake relief feature. Depending upon what you have there might be something on the brake arms, or where the cables exit the housing, or a flip-out lever on the brake handles, or a push button on the brake handle housing or hood. Sometimes the push buttons are hidden under the handlebar tape or under the brake hood covering. And on some older bikes you had to actually relieve the cable from the barrel adjusters on the handle assemblies to mount a wheel/tire.

I"m on the phone browser so I can't search what you're currently riding.

I have the release lever where the cable attaches to the brakes. It really doesn't open them much more.

I think I will ride to my LBS and discuss it with him. I really do need to support LBSs more rather than saving a few nickles on line. My closest LBS shut his doors earlier this year. No doubt a victim of online competition (well that and his shop looked like it had just been ransacked much of the time).

Probably not. The adjustment changes only the width, not the height. At least on my bikes, it's the height that's the issue.

Rub while you're riding or while you're removing it? If the latter, it can be an inconvenience but shouldn't be a dealbreaker to deflate a tire before removing and only reinflate it after installing.

I forgot about the height issue. I went out to the garage and the Univega has less than a 1/4" clearance for height. Some tire models/brands have different heights for their listed tire width, something to consider.

But if the OP has a Trek 520 just hanging around in the garage then run that one. Some of the 520's I've seen have room for studded tires with fenders on the bike.

If it turns out that a larger tire won't work out on the 1200, I may try this. Only problem is, the 520 is not really big enough for me. I bought it from a guy I work with because I got a nice deal on it. It is rideable, but, after 20 miles or so my back reminds me that I don't really fit that well on it. A longer seat post and different handlebar mount might fix this, but, probably cheaper to just find a suitable CL bike. Besides, I've been trying to get the wife into cycling and if she eventually comes around, the 520 will fit her as is just fine.

I was gonna say, the brakes open up only for wheel removal, not for tire clearance while riding. The pads still need to reach the rim to do their job.

On any bike, either the brakes, fork crown, rear triangle, or other frame features will determine how big of a tire you can use.

As an example, I can fit 700x28's on my FS MTB. It has disc brakes, so the brakes aren't a factor. There is clearance within the suspension fork, too. The BB is not an issue, and neither is the seat tube. However, the closest clearance is between the tire and a small reinforcement bracket that's bolted between the "chainstays". It's so close, in fact, that not all 700x28's will fit; a Continental SportContact is fine, but a Marathon Plus is just too big.

While I'm thinking about it -- on my road bike, the closest any part gets to a tire, either front or rear, is the rear brake bridge (more like a wishbone in this case). On my city bike with canti brakes, it's the fenders. On my fiancee's hybrid with V-brakes, it's hard to say -- either the fork crown, seatstays, or kickstand plate will limit tire clearance; but they leave so much space from its 700x28s that I can't guess how much bigger of a tire I can put on it.

Rode to my LBS on friday and explained how I was getting real tired of flats on my commute. Glad I went as I was convinced I could squeeze a 700x32 on, but, he assured me that a 28 was as big as I could go.

He recommended a pair of panaracer paselas and a set of tuffy tire liners. He says he's commuted on them for years and is very happy with them. Says that if I keep my tire pressure up, i shouldn't have any trouble.

Paid a bit more than I had wanted to (35 each), but, what the hell. If my throwing this guy some business helps keep him around it is money well spent. Also bought a road morph pump from him. He normally gets 40 for it, but, said he'd go to 30 when I told him I could get it for around that, since I was buying the tires also.

Just hope I'm done with flats for a while.

Anyone here have any opinions on the paselas?