scale

So i continue to read online that fatter tires are faster and actually provide less rolling resistance.

i decided to test this. My old 700x23s were worn out. I bought 25mm gatorskins and it is definitely much harder and more RR. It is night and day.

Looks like i have 1000s of miles to go slower now or get stronger

One thing that is kind of nice is that i was considering upgrading from 42x16 as my general gearing to something a bit harder as a feel it is time to move up. I have gained alot of strength cycling and was ready for the next step. I guess there is no need now as the tires put more work into my cycling for me. Its just a pity my speed isnt any better and feels slower.

Like i said....maybe the upside here is i will get stronger.

Dont get my wrong...the wider tire is a bit cushier and corners a bit better. Maybe this is where the gains happen? It sure doesnt seem to be rolling resistance.

NormanF

Balloon tires roll faster.

Schwalbe makes a line of them.

andr0id

Gatorskins aren't exactly know for being a fast tire.

What are you comparing to that wore out?

I run 700x25 GP 4000s and there's no difference to the 700x23 GP 4000 other than comfort.

You going to get skewed results comparing different brands or models.

PepeM

How much harder? How many more watts for the same speed?

knobster

Yeah, tires can be very different from one another and it is mainly due to the quality of the tire. I run 30/32's on my bikes and they as fast as 23's I've ran in the past. Difference is the tires I run are very high quality. 300 TPI and as light as a good 23.

scale

i had been running the cheapy forte kevelars from performance. I got a couple thousand miles on them before the sidewalls failed. They were quick tires i thought. I probably should have gone 23c gators but went 25s. They are much bigger. It is very noticeable on my single speed because i have no other gears to escape to. I guess im not complaining but a bit disapointed. The 23c gators on my road bike feel quite quick but i have more gearing to play with there. I was out on the single speed with the new 25s and i was toast after about 25 miles. Here's to hoping i get stronger before my knees start complaining. Like i said......the benefit here is maybe ill get stronger and be quicker on my other bikes.

Drew Eckhardt 

They are with all else equal, although there's a bigger difference between different tires (about 2:1 between fastest and slowest road tires) than different sizes of the same model.



The Gatorskin and GP 4 Season are slow tires regardless of width. The GP4000SII is fast, especially considering its flat resistance and durability.

There's 15-20W @ 20 MPH separating a GP4000S and Gatorskin or GP 4 Season. 20W is the difference between what I can manage for 10 minutes and a full hour.

Nope. A good training plan will make you stronger. Merely riding "fast" as many recreational riders try to do will not.

Jeff Wills

As others said, Gatorskins aren't known for their low rolling resistance. Also, well-worn tires will have lower rolling resistance than new, simply by having a more flexible casing.

Also, you don't mention how you tested this. The bike may feel different after the tire change, but that could just be the new tires. Did the bike go slower for the same power? How many test runs did you do?

AlmostTrick

The larger tire also raised your effective gear ratio a small amount. Likely you're feeling that too.

I'll never run 23's or 25's, too many disadvantages in the comfort and safety department. It really makes no sense when one can choose nice rolling, comfortable wider tires instead.

Wheever

When I went from the stock 25 Bontrager tires on my Domane to 28 GP 4000s, I dropped 6 seconds from my favorite strava segment. (A half-mile sprint.) my best time went from 1:16 to 1:10. I's been at the 1:16 mark for months, and now I'm stuck at the 1:10. Not precisely scientific, no, but demonstrably faster.

Elvo

You need fatter wheels to go along with the fatter tires

Needles

I put 1.95s on my cruiser, and temporarily put the 2.125 balloons on my MTB so I can get another hub laced onto it. I was surprised at how easily it rides. Since I'm converting it to a commuter, I might just go with the balloons! (Actually, the cruiser seems to roll more easily, too.)

pdlamb

Something that hasn't been mentioned is the road surface. On a track or smooth, freshly paved road, you may as well go with metal wheels (maybe with a rubber skin for traction). The "real world" tests that have been quoted include some gravel, road bumps, etc. Bad chipseal or expansion joints will make wider tires shine, or wear you down early. Cobblestones inspired Mr. Dunlop to invent pneumatic tires way back when, but many of those old bikes used 2" tires.

fietsbob

expensive , super light weight high thread count . supple casing wider tires are said to be faster .

Mr Heine, the proponent Often quoted, also happens to sell Compass Bike Tires, and did tests in his Magazine .

LUW

Keep in mind that one of the reasons that fat tires are faster is because they offer a more comfortable and stable ride, and with that you can put power more effectively to the ground.

gecho

GPS or regular cycling computer? Larger tires will make a non-GPS cycling computer read a lower speed. I experienced the opposite when going from knobbies to slicks on my mountain bike years back (wow these tires are so much faster!). 23 to 25 should be a very small difference though.

AlmostTrick

Not if you recalibrate it properly.

AlmostTrick

Yes, but the testing came before the tires, to help design a faster rolling tire. Not after, to prove an existing house product was superior. The proof is in the product.

fietsbob

they buy from a Japanese company that makes them . they may have made them before but rebadged for that Importer.

the performance need sacrifices all puncture resistant tread features of course.

AlmostTrick

I thought they were a new design and made by Panaracer for Compass. What I know for sure is I really like my Stampede Pass 32's. On two different bikes.

EDIT: As part of Bicycle Quarterly, Jan Heine routinely tested bicycle parts that weren’t readily available to the U.S. market. At times, he’d import small batches for their readers, including tires from Grand Bois and Challenge. Now, he’s decided to produce their own under the Compass brand.

The range is made for them by Panaracer, but are their own exclusive molds, designs and tread patterns.

PepeM

Where does that come from? Twenty watts are not to be ignored.

Drew Eckhardt 

The Tour Magazine 2012 test; roller tests from Tom Anhalt's, Al Morrison, and others; various people's derivation of CdA and Crr via RChung's virtual elevation model...

Here are some Crr measurements from Bicycle Rolling Resistance | Rolling Resistance Tests all with 25mm tires, at 100psi, on rollers.

I used the Crr to calculate power for a 80kg bike and rider combination (160 pound rider, 16 pound bike) at 20 MPH. Power scales linearly with weight and speed - multiply by 1.25 for power at 25 MPH, 1.1 for a 198 pound bike/rider combination, etc.

Andy Coggan found on-road Crr was .9428 * roller Crr + .0012. The specific correction varies, although that's a starting point.

GP 4000SII .00387; .00485 corrected
Continental Grand Prix 4000S II Rolling Resistance Review
27W on rollers
34W on road

GP 4 Season .00543; .00632 corrected
Continental Grand Prix 4 Season Rolling Resistance Review
38W on rollers + 11W
44W on-road - + 10W

Gatorskin .00606; .00691 corrected
Continental Gatorskin Rolling Resistance Review
43W on rollers +15W
49W on-road + 15W

They also measure the difference between 23, 25, and 28mm GP4000SII yielding .00393, .00387, and .00360 correcting to .00491, .00485, and .00459 which is to say the 23 is about 0.5W slower and 28mm 2W faster on-road.

Continental Grand Prix 4000S II 23 25 28 mm Comparison

Other tests show bigger differences.

The 2012 Tour Magazine test reported 53.9W for the GP 4 Season with 85kg @ 35km/h which is 46.7W for 80kg @ 20 MPH; and 34.3W for the GP4000S which scales to 29.7W for a 17W difference between the two.

https://www.conti-tyres.co.uk/conticy...20Fighters.pdf

Mandeville

I recently replaced my Bontrager Hard Case Lite 25c tires with the same model Bontrager 28c tires. I'm definitely faster on climbs. (I've not done enough comparable flat ridings to ascertain accurate data to determine what difference there is.)

Some specifics: One minute and five seconds faster up a 1.4 mile 7-8 percent grade. One and one half minutes faster on a five mile Category 3 climb. The preceding are just two examples. I'm faster on all climbs.

AlmostTrick

What difference in pressure do you run between the two?

SouthFLpix

Yes, but often wider tires are designed with puncture resistance and durability in mind rather than speed. If you have a wider racing tire that is lightweight and supple, yes it will be faster (less rolling resistance). That however, won't apply to something like a Schwalbe Marathon tire.