CX/Gravel Tire Test: Challenge Gravel Grinder 33
Contents and Test Summary
- Introduction
- Manufacturer Specifications
- Size, Weight, Thickness
- Rolling Resistance: 28.7 Watts
- Puncture Resistance: 62 Points
- Static Wet Grip: 53 Points
- Conclusion: 3.5 / 5 Recommended
- Comments
- Challenge Gravel Grinder 33
(100% is best)
The Challenge Gravel Grinder is a cx/gravel bike tire with a diamond tread in the center and bigger knobs along the edge of the tire. From the outside, the Gravel Grinder looks like it should be faster rolling than the Challenge Grifo Pro (read our review) that we tested a couple of weeks back and which is a much knobbier tire.
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Just like many other tires from Challenge, the Gravel Grinder is available in a lot of different versions. We're testing the handmade Pro version that comes with a tan-colored 260 TPI SuperPoly casing with an extra layer of PPS2 anti-puncture material under the tread.
The Gravel Grinder Pro is available in both a 33 and 36 mm wide version. We've tested the 33 mm version as we had a hard time finding the bigger version.
Manufacturer Specifications
Manufacturer Specs | |
---|---|
Brand | Challenge |
Model | Gravel Grinder |
Year | 2020 |
Supplied By | Bought in store |
New or Used | New |
Mileage | 0 km |
Price Range | High |
Buy At | Ad Amazon.com |
Manufacturer part number | 00535 |
EAN | 8855627005356 |
TPI | 260 |
Compound | |
Bead | Folding |
ETRTO | 33-622 |
Specified Weight | 0 grams |
Max Air Pressure (psi) | 75 |
Made In | Members Only |
Available Sizes |
33-622 (700x33x) 36-622 (700x36c) |
Challenge Gravel Grinder 33 Test Results
Size, Weight, and Thickness Measurements
Size, Weight, and Thickness Measurements | |
---|---|
Specified Weight | 0 grams |
Measured Weight | 412 grams |
Measured Width Casing | 33 mm (un-round) |
Measured Width Tread | 33 mm |
Measured Height | 31 mm (un-round) |
Measured Knob Height Center | 0.7 mm |
Measured Knob Height Edge | 2.3 mm |
Measured Total Thickness Center (excluding knobs) | 2.60 mm |
Measured Total Thickness Sidewall | Members Only |
All size measurements are taken at low air pressure on a 17.8 mm inner width rim. |
Rolling Resistance Test Results
Rolling Resistance Test Results | |
---|---|
Inner Tube | Conti Cross28 (160 gr) |
Measured Width | 33 mm |
Rolling Resistance Real tire width in mm: 30-32 = 66 psi/4.6 bar 33-35 = 60 psi/4.1 bar 36-38 = 54 psi/3.7 bar 39-42 = 50 psi/3.4 bar 43-46 = 46 psi/3.2 bar 47-50 = 42 psi/2.9 barHigh Air Pressure (60 psi / 4.1 bar) |
Members Only |
Rolling Resistance Real tire width in mm: 30-32 = 55 psi/3.8 bar 33-35 = 50 psi/3.4 bar 36-38 = 45 psi/3.1 bar 39-42 = 42 psi/2.9 bar 43-46 = 38 psi/2.6 bar 47-50 = 35 psi/2.4 barMedium Air Pressure (50 psi / 3.4 bar) |
Members Only |
Rolling Resistance Real tire width in mm: 30-32 = 44 psi/3.0 bar 33-35 = 40 psi/2.8 bar 36-38 = 36 psi/2.6 bar 39-42 = 33 psi/2.3 bar 43-46 = 31 psi/2.1 bar 47-50 = 28 psi/1.9 barLow Air Pressure (40 psi / 2.8 bar) |
28.7 Watts CRR: 0.00860 |
Rolling Resistance Real tire width in mm: 30-32 = 33 psi/2.3 bar 33-35 = 30 psi/2.1 bar 36-38 = 27 psi/1.9 bar 39-42 = 25 psi/1.7 bar 43-46 = 23 psi/1.6 bar 47-50 = 21 psi/1.4 barExtra Low Air Pressure (30 psi / 2.1 bar) |
33.9 Watts CRR: 0.01016 |
The CX/Gravel 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. |
Puncture Resistance Test Results
Puncture Resistance Test Results (higher is better) | |
---|---|
Total Puncture Score Tread | 62 Points |
Total Puncture Score Sidewall | Members Only |
Tread Puncture Force Sharp Needle | 15 |
Tread Puncture Force Blunt Needle | Members Only |
Tread Total Tire Thickness | 2.60 mm |
Sidewall Puncture Force Sharp Needle | Members Only |
Sidewall Puncture Force Blunt Needle | Members Only |
Sidewall Total Tire Thickness | Members Only |
Hard Surface Static Grip Test Results
Static Grip Test Results | |
---|---|
Wet Grip Average | 53 Points |
Wet Grip Center | Members Only |
Wet Grip Edge | Members Only |
Measured Knob Height Center | 0.7 mm |
Measured Knob Height Edge | 2.3 mm |
Grip in points = coefficient of friction * 100 CX/Gravel grip test rim width = 23.0 mm |
|
Wet Grip Test and Off-Road Tires (info) | |
Conclusion
- Challenge Gravel Grinder 33
(100% is fastest - lightest - highest - strongest)
The Gravel Grinder Pro scores very well in the tread puncture resistance test. The sidewalls on the other hand are quite weak which makes this an unbalanced tire in the puncture resistance department. Rolling Resistance isn't all that low although when compared to the fastest tires, the difference is manageable.
This can be a good tire if it fits your specific needs. We're not all that excited about this tire as the weak sidewalls can become a problem on gravel. Check the CX/Gravel overview page to compare for yourself.
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RATING:
3.5
/ 5
TEST VERDICT:
Recommended