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.
|Tire Type||Tubetype (clincher)|
|Supplied By||Bought in store|
|New or Used||New|
|Specified Weight||245 grams|
28-559 (26x1 1/8)
Size and Weight Measurements
|Size and Weight Measurements (Bike Wheel: 622x17C, Pressure: 100 psi / 6.9 bar)|
|Specified Weight||245 grams|
|Measured Weight||239 grams|
|Measured Width||26 mm|
|Measured Height||24 mm|
|Total Tire Thickness Center||No Data|
|Total Tire Thickness Sidewall||No Data|
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 (Speed: 29 kmh / 18 mph / 8 m/s, Load: 42.5 kg / 417 N)|
|Inner Tube||Conti Race28 (100gr butyl)|
|Rolling Resistance 140 psi / 9.7 Bar||
CRR: Not Tested
|Rolling Resistance 120 psi / 8.3 Bar||
|Rolling Resistance 100 PSI / 6.9 Bar||
|Rolling Resistance 80 PSI / 5.5 Bar||
|Rolling Resistance 60 PSI / 4.1 Bar||
|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)|
|Puncture Resistance Tread||13|
|Puncture Resistance Sidewall||Not Tested|
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.
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.
TEST VERDICT: Recommended