Tire size tradeoffs
 

I have been commuting on a road bike with 23mm tires (Conti Gator skins after my old tires got several flats).

I am looking at a new bike which will allow a larger size tire as well as fenders, etc. as well as likely Steel for better ride

I am trying to decide WHAT size tire I would like to get.

For reference, I commute just over 16 miles each way, climb about 450 feet each way, and am on roads or bike paths the entire time. The roads/paths can be a bit rough at time and there are unavoidable obstacles in areas.

I could just stick with 23mm, which would be the fastest but also I assume least comfortable and most prone to flats. Alternatively I could go with a larger tire - 25, 28 or maybe even 32mm. Not sure I want to step up all he way to 32, but wonder how different 25 vs 28 would be and how different they would be the just going with 23mm in terms of tradeoff of ride vs speed due to additional rotational weight.

Ideally I would try riding with different size tires to see what I like, but the tires cost enough I am not sure I want to buy two sets to decide :)

Any input from people who have tried different tire sizes on the same bike is appreciated.

I went from 23 to 25 on my road bike and didn't lose any speed.

For commuting I would go 28 or 32.

If you aren't riding at the level to get your tires free, I doubt you would actually feel any difference on the bike.

I used to think 28mm was my favorite size. Then I got 32mm tires. Mmm, cushy.

I took a club ride with 9 other riders on Sunday. It was on a trail, and I had the narrowest tires of everyone, even though most people had road bikes. Wide tires are much better than they used to be. They really rock. I say get a bike that can accept at least 32mm, perhaps more. I know people who want them much wider. On Sunday, I got pretty jostled, and some people were just gliding over the roots and ruts.

I'm running 35s at 90 psi on my commuter (CX) and don't think they really slow me down much. Sure are comfy.

I'm running my 32s at 50 or 60 psi. I weigh 170 lbs, and my bike is 40 lbs.

On 5 out of my 6 bikes....I run the fattest tires the frame will fit. There are no tradeoffs.

I have a choice of routes, but the one I use most often is very similar to yours--16.5 miles, about 400 feet of climbing, half road, half paved MUP, and the MUP can be rough with tree roots corregating the surface. (But the roads are nice.)

First, I've found Continental Grand Prix 4-Seasons to be just as trouble-free as Gatorskins, but they provide a considerably more comfortable ride and they're super grippy in the wet. The downside is that their thread life is somewhat less. I always found the Gatorskins to be too skittish in the wet, so I'm willing to give up some tread life for better wet grip and better ride all the time. YMMV.

I've run GP 4-Seasons in 23, 25 and 28. There is considerable improvement in ride quality as you go bigger, if you adjust air pressure accordingly. However, I've not found any difference in either speed or climbing ability between them. Since there's only a 30 gram difference between the 23 and 28, there's no real penalty there either.

So I run the biggest ones that will fit in my frames--28 under full fenders on the commuters, 25 on open wheels on the roadie.

Thanks for the info, tsl. I hadn't considered the conti GP 4 seasons, though I have seen it at some LBSs. Not sure if I really need the 4-seasons part of it as we really only have three seasons here :) That said grip when wet will be an important factor for me so i may have to look at these. They seem to have a lot more "tread" then the gators, does that impact ride/handling/grip?? They only go up to 28 from the website, so that choice would eliminate the option of 32s. I may try a pair this winter even if its just for the wet grip.

Bear in mind that when I say four-seasons it's a lot different than when tire manufacturers (and other cyclists) say four-seasons. To almost everyone else, the fourth season is rain, not snow. (For snow, I use Nokian Hakkapeliitta W106 studded snow tires in 35/38mm.)

As for the Conti GP 4-Seasons, it's the tread compound that impacts the grip. The rubber is just plain stickier. Construction and the use of a Vectran breaker instead of Kevlar is what does it for the ride. Handling comes from a little bit of each, I expect.

Don't forget, the bigger your tire, the lower the pressure. I run my 28s (on the wide 23mm rims) at between 60 and 65 in the front, and 70-75 in the rear. See Tire Drop for details.

EDIT: The best pricing on Contis I've found in the States is from TireManiacs.com. Their prices include shipping to the lower 48.

The benefits of narrower tires, supposedly being faster, are greatly exaggerated. All things being equal, wider tires actually can have lower rolling resistance. But all things are never equal, so the drawback of wider tires is mainly added weight.

As long as you can find decently light tires with smooth tread, buy the widest tires that give you the fender clearance you also want.

I just switched the tires on my roadie from 23mm Gatorskins to 25mm 4 Seasons and really like the feel.

Thanks for the clarification and link (though when I tried to to there it gave me "server application unavailable" error). I have also seen these at a number or local shops, so might be reasonable to get them local particularly if I can get them with a bike coalition discount or something similar.

Any idea if the Vectran is as effective as Kevlar? I have been VERY happy with the flat resistance of the gatorskins.

I am thinking about trying a set of these in 28s for the winter and comparing the performance with the Gators on my current bike.

I knew that larger tires mean lower pressure, but I am curious as to why you run you rears higher then the fronts - is it as more weight is on the rear or something with handling? Maybe this answer will be in the Tire Drop link you provided, which I will try to read soon.

Thanks for the input. I wonder how much of this is size and how much is different material of the 4 Seasons.

Running 35x700 panaracer paslea tourguard. 55 psi front, 60 rear. Loaded crosscheck with 235lbs rider. Works great for me. Never thought about going narrower. Works good on the regular road, dirt paths and occasional singketrack.

I've run 28 (Panaracer Ribmo) & currently 32 (Panaracer Pasela TG) on one commuter and 40 (Michelin City) on another. (On my "road" bike it's Continental GP4000s 25c with 90 front/100 rear.)

Personally the biggest benefit I've found is the ability to run lower tire pressures in wider tires. With the 32c it's 60psi front/70psi rear and with the 40c it's 40psi front & 50psi rear.

Personally going from 23 to say, 28 you will notice a difference, but make sure to experiment with tire pressure.

I run 32s at 70psi. I weigh 142 and the bike weighs 40. Current tires/tyres are the stock ones on my Allant - Bontrager H2 with reflective sidewalls. I've gotten four flats in 1800 miles, one of which caused by a nail and another caused by a small piece of gravel penetrating the tread and just barely scraping the tube.

I think that the wheels and the bike itself make much more difference in speed than the tires do.

Tread does make a difference in speed, but if you're on roads and paved MUPs, it will make almost no difference in the wet; it's more for going off the road. Hybrid tread is good for fine gravel paths. Slicks are fine for the road, dry or wet.

I would recommend trying some 28s before jumping all the way to 32s. I commute on 23, 25, 28 and 32 mm tires on various bikes and they are all comfortable to me -- but all of my bikes are steel and the roads on my route are pretty decent. Wider tires are generally heavier, so there is a tradeoff if your route has a lot of hills. On flats, the wider tires shouldn't slow you down unless their rolling resistance is higher.

Some good 28s include the aforementioned Conti GP 4 Seasons, Vittoria Rubinos, Clement Stradas and Rivendell Rolly Poly or Ruffy Tuffys. I've used the 4 Seasons and Rubinos extensively, having good experiences with both but prefer the ride of the Vittorias over Contis. Look for tires with folding beads if your route has much climbing.

Controlled experiment..

Need to set up 2 identical bikes. with only the tire different.

the tendency after doing the work, spending the Money,

is to consider the new thing better, to justify the work done and money spent.

even though there is no 'before' left to compare it with, anymore.
and there may actually be no real, significant difference ..


Like choosing 1 brand of guitar string over another , if they are Other wise made of same stuff.

Switched this summer to 32 at 80 psi from 25's at 100 psi. Barely noticed a
difference in speed or effort on a 24 mile roundtrip commute with 20 or so lights.
But the difference in ride is nite and day. Next time I will probably go to 35's.
Bike is between 40 and 45lbs.fully loaded and I'm 175.

I can only report my experience.

I too was concerned about that, but I've found the puncture resistance is about the same. The biggest differences between the two are ride quality and wear. I get about the same distance on the fronts between the two models, but I got twice the mileage out of the Gators on the back. Again, you can't have everything, so it's a trade-off I make for the ride and wet grip. So you may want to start out with a set of three.

It may take a while for you to get used to wider tires, but i would suggest not limiting yourself to the sizes you cited. I went from 23mm to 40mm (Trek Madone to Salsa Vaya) and really like the ride waaaay better. Now last night I switched out to 35mm and will likely stay there. Schwalbe Marathon Supremes - not flats in 2 years on the 40mm tires and they still look newish (maybe 2000 miles). I got the 35mm editions on Ebay for $58 (they are usually $75).

Go wider young man!

It depends on how much you weigh. At 200 pounds you want 25mm tires to keep the inflation pressures needed to avoid pinch flats down to 90-95 in front and 100-15 in rear loosing a few pounds a day.

At 140 pounds you don't need 90psi in 23mm tires.

All else equal wider tires have lower rolling resistance, although the fastest designs are only made out to 25mm wide (next year Continental will release their GP4000S II in widths to 28mm).

25mm tires with lower pressure than 23s as a fat guy feel better.

At 145 pounds I would not bother. At 195 pounds I'd definitely get the 25s.

I've ridden Gatorskins, GP4000S, and GP4 Seasons in 25mm.

The Gatorskins are fast and ride well for tires that puncture resistant and long lasting (not bricks like Specialized Armadillos) . In absolute terms they're not that fast or nice.

The GP4000s ride nice and are fast. They are not long lasting.

The GP4 Seasons are an answer in search of a problem. They ride fine, but are slow tires and last half as long as the Gatorskins. If you're OK with the lifespan you want the GP4000. If not you want the Gatorskins They might make sense if you plan on racing in the rain where corning a hair faster than with GP4000s (which are stickier than the Gatorskins) would help you win, although if you're like me and in no hurry cornering in the rain (going over a manhole cover or cross-walk stripe can really suck with some speed) you're not going to stress your tires enough for the difference to matter.

The GP4000s and GP4 Seasons don't seem to flat appreciably more often for me than the Gatorskins (which is rarely). The GP4 Seasons and Gatorskins do have more sidewall protection which might matter in situations like gravel.

I'm also 195 and run 700x25 Conti GP 4-seasons at 85 PSI front and 95 PSI rear, based on the Tire Drop article, and the measured weight on each tire (using the bathroom scale and a block of wood lol).