CX/Gravel Tire Test: IRC Boken Doublecross 42

The IRC Boken Doublecross is available in the 33, 38, and 42 mm sizes and doubles as both a CX race tire and an all-round gravel bike tire. Something to be aware of is that the 33 mm version comes with a much different tread pattern than the 38 and 42 mm versions, and our test results might be less useful when you're interested in the 33 mm version.

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The 42 mm version of the Boken Doublecross is also the first gravel bike tire from IRC we've tested. It is always interesting to test new brands as it will give a good indication of the casing and compound performance of other tires in the same family that often share the same base construction and compound.

Both the 38 and 42 mm versions of the Boken Doublecross come with a nearly continuous center tread and relatively widely spaced knobs along the tire's edge, making it suitable for an extensive range of gravel bike conditions. The 60 TPI casing comes with reinforced sidewalls, tubeless-ready beads, and inflating the tire on our tubeless-ready rim was as easy as it gets. Air retention also was excellent, and there was no air loss during the tests.

The Boken Doublecross comes with the similarly named "Boken compound", and according to IRC, it's their grippiest rubber. Our test results confirm the grip part, but it comes at the cost of rolling performance.

Let's roll on to the rest of the test results and see how the Boken Doublecross compares to the competition.

Manufacturer Specifications

Manufacturer Specs
Brand	IRC
Model	Boken Doublecross
Year	2023
Supplied By	Bought in store
New or Used	New
Mileage	0 km
Price Range	High
Buy At	Ad Amazon.com
Manufacturer part number	190587
TPI	60
Compound	Boken compound
Bead	Folding
ETRTO	42-622
Specified Weight	530 grams
Max Air Pressure (psi)	50
Made In	Members Only
Available Sizes	33-622 (700x33c) 38-622 (700x38c) 42-622 (700x42c)

IRC Boken Doublecross 42 Test Results

Size, Weight, and Thickness Measurements

Size, Weight, and Thickness Measurements
Specified Weight	530 grams
Measured Weight	559 grams
Measured Width Casing	42 mm (un-round)
Measured Width Tread	40 mm
Measured Height	40 mm (un-round)
Measured Knob Height Center	2.1 mm
Measured Knob Height Edge	2.1 mm
Measured Total Thickness Center (excluding knobs)	2.30 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)
Measured Width	42 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
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
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)	26.3 Watts CRR: 0.00788
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)	29.8 Watts CRR: 0.00893
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	2.30 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	70 Points
Wet Grip Center	Members Only
Wet Grip Edge	Members Only
Measured Knob Height Center	2.1 mm
Measured Knob Height Edge	2.1 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 IRC Boken Doublecross isn't the fastest rolling gravel bike tire, as it comes in near the bottom of the list of 65 gravel bike tires tested to date. Given its relatively fast-looking tread pattern, we expected the Boken Doublecross to do better here. It's once again a confirmation that a tire's tread pattern only has a marginal impact on rolling resistance.

When looking at puncture resistance, we also see the Doublecross near the bottom of the list. That leaves only one explanation for the relatively high rolling resistance, which we find in the wet grip tests on our hard test surface. The Boken Doublecross performs very strongly in the center wet grip test, which shows the compound's potential due to the nearly continuous center tread. The wet grip in the edge test comes in lower because of the limited contact area that the very widely spaced edge knobs provide.

Of course, this is all on our hard test surface, and the results will vary on other surfaces where the knobs can dig in.

We don't think the IRC Boken doublecross is a bad tire but don't expect this to be a super fast or puncture-resistant tire.

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RATING: 2.8 / 5
TEST VERDICT: Recommended

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