CX/Gravel Tire Test: Zipp G40 XPLR 40

Zipp is best known for their carbon wheels, but they also make some tires to supplement those wheels. The Zipp G40 XPLR is their first try at a gravel bike tire, and to cover a large audience, the G40 is a versatile tire that should suit a large range of conditions.

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A gravel bike tire that suits a large range of conditions usually comes with a denser tread pattern in the center to make it roll well on asphalt and more aggressive knobs along the edge of the tire to create some cornering grip under off-road conditions. This is also exactly the setup the G40 XPLR comes with, and from the looks of it, the tread pattern looks like a good tradeoff for most conditions.

The construction of this tire seems quite conservative as we find a 127 TPI casing with a bead-to-bead puncture protection strip which is common on many other tubeless-ready gravel bike tires. We also find hookless compatibility on the spec sheet as Zipp seems to push hookless rims. Unfortunately, we can't find anything about the compound on this tire which makes us suspect Zipp hasn't put any effort into this area.

We're not sure if it was intentional or a coincidence, but the G40 is only available in the 40 mm size. While most manufacturers release their tires in several different sizes, Zipp seems convinced the 40 mm size is the one to go for on gravel bikes.

Manufacturer Specifications

Manufacturer Specs
Brand	Zipp
Model	G40 XPLR
Year	2022
Supplied By	Bought in store
New or Used	New
Mileage	0 km
Price Range	Very High
Buy At	Ad Amazon.com
Manufacturer part number	00.1918.192.140
TPI	127
Compound	-
Bead	Folding
ETRTO	40-622
Specified Weight	480 grams
Max Air Pressure (psi)	65
Made In	Members Only
Available Sizes	40-622 (700x40c)

Zipp G40 XPLR 40 Test Results

Size, Weight, and Thickness Measurements

Size, Weight, and Thickness Measurements
Specified Weight	480 grams
Measured Weight	473 grams
Measured Width Casing	39 mm (un-round)
Measured Width Tread	41 mm
Measured Height	37 mm (un-round)
Measured Knob Height Center	1.6 mm
Measured Knob Height Edge	2.0 mm
Measured Total Thickness Center (excluding knobs)	1.50 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	None (30 ml sealant) (current protocol)	Conti Cross28 (160 gr) (test protocol)
Measured Width	39 mm	39 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 (50 psi / 3.4 bar)	Members Only	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 (42 psi / 2.9 bar)	Members Only	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 (33 psi / 2.3 bar)	23.3 Watts CRR: 0.00698	27.1 Watts CRR: 0.00812
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 (25 psi / 1.7 bar)	27.7 Watts CRR: 0.00830	32.7 Watts CRR: 0.00980
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	30 Points
Total Puncture Score Sidewall	Members Only
Tread Puncture Force Sharp Needle	Members Only
Tread Puncture Force Blunt Needle	Members Only
Tread Total Tire Thickness	1.50 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	75 Points
Wet Grip Center	Members Only
Wet Grip Edge	Members Only
Measured Knob Height Center	1.6 mm
Measured Knob Height Edge	2.0 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

The Zipp G40 XPLR is an average performer in our tests. The weakest point seems to be the puncture resistance of both the tread and sidewalls. The low scores here are probably also partly attributed to the "fishnet" style puncture protection that will only work well on punctures bigger than 3 mm. Objects that are smaller than 3 mm will go through easily as the casing material seems made of a very soft material.

We tried puncturing through the reinforced "wires" of the sidewall but found the puncture needles to slide off the reinforced parts into the soft parts as it's laid out on top of the sidewalls. We expect most objects that want to penetrate the sidewalls to act similarly. With enough sealant in the tires, Punctures up to 1-2 mm shouldn't cause a huge problem.

The good part is that, although it isn't the fastest rolling compound, it's a very grippy compound offering excellent wet center grip. Given the wider spaced knobs, the wet edge grip on hard surfaces is pretty decent as well (grip data available through Pro View for now).

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RATING: 3.3 / 5
TEST VERDICT: Recommended

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