Road Bike Tire Test: Continental Grand Prix 25
Contents and Test Summary
- Introduction
- Manufacturer Specifications
- Size, Weight, Thickness
- Rolling Resistance: 15.9 Watts
- Puncture Resistance: No Data
- Static Wet Grip: No Data
- Conclusion: 4.0 / 5 Recommended
- Comments
The Continental Grand Prix 700 x 25C is a medium priced road bike tire. It's handmade in Germany, has a 3/180 TPI carcass, PolyX puncture protection, and the Continental Black Chili compound for reduced rolling resistance, more grip, and higher mileage. You get quite a lot for your money with this tire. The Grand Prix is pretty much a cheaper version of the Grand Prix 4000S II tire from Continental. Continental specifies the Grand Prix as a Tour / Race tire while the Grand Prix 4000S II gets specified as a Tour / Race / Time Trial tire.
I choose to test this tire because I wanted to know how a cheaper choice in a manufacturers tire line-up compares to the top of the line product. While most other manufacturers top of the range tires are manufactured in low-labor-cost countries, it's a surprise the packaging says this medium priced Continental is handmade in Germany.
Manufacturer Specifications
| Manufacturer Specifications | |
|---|---|
| Brand | Continental |
| Model | Grand Prix |
| Year | 2014 |
| Tire Type | Tubetype (clincher) |
| Supplied By | Bought in store |
| New or Used | New |
| Mileage | 0 km |
| Price Range | Med |
| Buy At | |
| Manufacturer part number | 0100637 |
| TPI | 3/180 |
| Compound | Black Chili |
| Bead | Folding |
| ETRTO | 25-622 |
| Size Inch | 28" |
| Specified Width (mm) | 25 |
| Specified Weight | 245 grams |
| Max Air Pressure (psi) | 120 |
| Made In | Pro Data |
| Available Sizes |
23-622 (700x23C) 25-622 (700x25C) 28-622 (700x28C) 23-571 (650x23C) 28-559 (26x1 1/8) 28-406 (20x1.10) |
Continental Grand Prix 25 Test Results
Size, Weight, and Thickness Measurements
| Size, Weight and Thickness Measurements | |
|---|---|
| Specified Weight | 245 grams |
| Measured Weight | 239 grams |
| System Adjusted Weight (tire + inner tube (100 gr) |
339 grams |
| Measured Width | 26 mm (un-round) |
| Measured Height | 24 mm (un-round) |
| Total Tire Thickness Center | No Data |
| Total Tire Thickness Sidewall | Pro Data |
| Unmounted Casing Width | No Data |
| Unmounted Tread Width | No Data |
| Tread Cover (Tread / Casing Ratio) | No Data |
| All size measurements are taken at an air pressure of 100 psi / 6.9 bars on a 17.8 mm inner width rim. | |
The measured weight of the Continental Grand Prix is a bit higher than more expensive tires but with a weight of 239 grams, comes in lower than the specified weight of 245 grams. This tire is close to a true 25C tire with a width of 26 mm and a height of 24 mm on a 17C rim.
Rolling Resistance Test Results
| Rolling Resistance Test Results | |
|---|---|
| Inner Tube | Conti Race28 (100gr butyl) |
| Measured Width | 26 mm (un-round) |
| Rolling Resistance Real tire width in mm: 22-24 = 132 psi/9.1 bar 25-27 = 120 psi/8.3 bar 28-29 = 108 psi/7.4 barUltra High Air Pressure (120 psi / 8.3 bar) |
Pro Data |
| Rolling Resistance Real tire width in mm: 22-24 = 110 psi/7.6bar 25-27 = 100 psi/6.9 bar 28-29 = 90 psi/6.2 barExtra High Air Pressure (100 psi / 6.9 bar) |
Pro Data |
| Rolling Resistance Real tire width in mm: 22-24 = 88 psi/6.1 bar 25-27 = 80 psi/5.5 bar 28-29 = 72 psi/5.0 barHigh Air Pressure (80 psi / 5.5 bar) |
15.9 Watts CRR: 0.00477 |
| Rolling Resistance Real tire width in mm: 22-24 = 66 psi/4.6 bar 25-27 = 60 psi/4.1 bar 28-29 = 54 psi/3.7 barMedium Air Pressure (60 psi / 4.1 bar) |
Pro Data |
| The Road Bike section is a multi tire size section, air pressures have been adjusted to the measured casing width. All numbers are for a single tire at a speed of 29 km/h / 18 mph and a load of 42.5 kg / 94 lbs. Use the formula: RR (Watts) = CRR * speed (m/s) * load (N) to calculate rolling resistance at a given speed and load. |
|
Performance is excellent for a tire in this price range. Rolling resistance is a bit higher when compared to the top of the line road bike tires. At an air pressure of 120 psi, rolling resistance is 14.0 watts. 14.0 watts is 1.8 watts higher than the more expensive Continental GP4000S II which came in at 12.2 watts. At an air pressure of 100 psi, rolling resistance is excellent at 14.5 watts. Dropping air pressure to 80 psi results in 15.9 watts of rolling resistance.
Puncture Resistance Test Results
| Puncture Resistance Test Results (higher is better) | |
|---|---|
| Total Puncture Score Tread | No Data |
| Total Puncture Score Sidewall | Pro Data |
| Tread Puncture Force Sharp Needle | 13 Points |
| Tread Puncture Force Blunt Needle | No Data |
| Tread Total Tire Thickness | No Data |
| Sidewall Puncture Force Sharp Needle | Pro Data |
| Sidewall Puncture Force Blunt Needle | No Data |
| Sidewall Total Tire Thickness | Pro Data |
While rolling resistance is a bit worse than more expensive tires, puncture resistance is a bit better. With a score of 13, it outperforms the GP4000S II by 2 points in the puncture resistance test.
Static Grip Test Results
NOTE: Grip test data is only available on tires tested after November 2018. You can find more information about our grip test here: Introducing Grip Testing
| Static Grip Test Results | |
|---|---|
| Wet Grip Average | No Data |
| Wet Grip Center | No Data |
| Wet Grip Edge | No Data |
| Grip in points = coefficient of friction * 100 Road bike grip test rim width = 19.0 mm |
|
Conclusion
With a rise in rolling resistance of only 0.5 watts, the Continental Grand Prix performs very well at 100 psi / 6.9 bars. At 80 psi / 5.5 bar performance is still good but compared to more expensive tires the differences start to become bigger. It seems performance of cheaper tires is still decent, and the difference is much smaller than I expected it would be. When you're just touring for fun, you probably won't notice the difference.
For the price of a single Grand Prix 4000S II, you can almost buy a pair of Grand Prix. Rolling resistance will be 4 to 7 watts higher for a pair of tires when making a correction for an average road bike speed of 23 mph / 36 km/h. You also have to carry 40-50 grams extra weight, but you'll gain 18% in puncture resistance. What you also get is the same Black Chili compound, which I know has excellent grip and little wear.
RATING:
4.0
/ 5
TEST VERDICT:
Recommended