Fat Bike Tire Test: Surly Larry

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  • Surly Larry
Performance compared to all other fat bike tires
(100% is fastest - lightest - highest - strongest)
Pro Members get 9-point radar charts

Surly Larry road bike tire on a rolling resistance test machine

The Surly Larry is a tire designed specifically as a front tire for fat bikes. It features a series of dart shaped knobs and tiny domes in between the knobs that supposedly combine traction and drift control. This is a review of the folding 120 TPI version as that version is the lightest and should also be the fastest. A cheaper 27 TPI wire bead version of this tire is available as well.


Just like the 45NRTH fat bike tires, the Surly fat bike tires are expensive. The high prices set high expectations so I'm really looking forward to testing this tire to see if the Surly tires are worth the money. I couldn't find much information about rubber compounds, puncture layers, reinforcements or other specifications of the Surly tires so let's just test this tire and see where it ends up.


Manufacturer Specifications


Manufacturer Specifications
Brand Surly
Model Larry
Year 2016
Supplied By Bought in store
New or Used New
Mileage 0 km
Price Range High
Buy At
Manufacturer part number
TPI 120
Compound
Bead Folding
ETRTO
Size Inch 26"
Width Inch 3.80
Specified Weight 1256 grams
Max Air Pressure (psi) 30
Made In Members Only
Available Sizes 26x4.70
26x3.80

Surly Larry Test Results

Surly Larry  fat bike tire on a rolling resistance test machine

Size, Weight, and Thickness Measurements


Size, Weight, and Thickness Measurements
Specified Weight 1256 grams
Measured Weight 1212 grams
Measured Width Carcass 93 mm (un-round)
Measured Width Tread 90 mm
Measured Height 80 mm (un-round)
Measured Knob Height Center 4.5 mm
Measured Knob Height Edge 4.5 mm
Measured Total Thickness Center (excluding knobs) 2.50 mm
Measured Total Thickness Sidewall Members Only
All size measurements are taken at an air pressure of 16 psi / 1.1 bars on a 65 mm inner width rim.

Some of the sparse technical data about the Larry is that it should have a weight of close to 1256 grams. My sample comes in at 1212 grams and makes this one of the few tires that actually weigh less than the specified weight. The measured casing width on a 65C rim at an air pressure of 16 psi is 93 mm. The shoulder knob to shoulder knob width is 90 mm. The 3.80 rating on this tire seems to make sense as it's a bit smaller than the 4.00 rated tires.


The center and shoulder knobs on the Larry all have the same height of 4.5 mm which is a middle of the pack knob height for a fat bike tire. The sidewalls have an average thickness of about 0.9 mm which also fits the middle of the pack.


Rolling Resistance Test Results


Rolling Resistance Test Results
Inner Tube None (60 ml sealant)

(current protocol)
Schwalbe SV13J (390 gr)

(test protocol)
Rolling Resistance 20 PSI / 1.4 Bar Members OnlyMembers Only
Rolling Resistance 16 PSI / 1.1 Bar Members OnlyMembers Only
Rolling Resistance 12 PSI / 0.8 Bar 32.2 Watts
CRR: 0.00965
37.7 Watts
CRR: 0.01130
Rolling Resistance 8 PSI / 0.6 Bar 40.9 Watts
CRR: 0.01226
48.4 Watts
CRR: 0.01451
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.

Rolling resistance of the Larry isn't very low, but it does outperform the equally expensive tires from 45NRTH. Compared to the top performing tires, more than 10 watts is lost per tire at the low air pressure of 8 psi / 0.6 bars. At higher air pressures, the difference is a bit smaller but still significant.


As most Surly tires seem to use the same construction and probably come out of the same factory, I don´t expect their other tires to magically perform much better in the rolling resistance test. For the money they ask for this tire, I feel it disappoints.


Puncture Resistance Test Results

Surly Larry  fat bike tire on a rolling resistance test machine
Puncture Resistance Test Results (higher is better)
Total Puncture Score Tread 30 Points
Total Puncture Score Sidewall Members Only
Tread Puncture Force Sharp Needle 6 Points
Tread Puncture Force Blunt Needle Members Only
Tread Total Tire Thickness 2.50 mm
Sidewall Puncture Force Sharp Needle Members Only
Sidewall Puncture Force Blunt Needle Members Only
Sidewall Total Tire Thickness Members Only

Surprisingly, the Larry doesn't perform that well in the puncture resistance tests either. With scores of 6 in the tread puncture test and 4 points in the sidewall puncture test, it comes in at the bottom of the pack.


Conclusion


  • Surly Larry
Performance compared to all other fat bike tires
(100% is fastest - lightest - highest - strongest)

Pro Members get 9-point radar charts

The Surly Larry doesn´t impress me at all. A couple of years ago this tire might have been a good option, but other tires have become available that greatly outperform this tire. When you like to run your tires at very low air pressures, it´s important to have tires that provide a low rolling resistance. Compared to the Surly Larry, the best rolling fat bike tires can save 25+ watts of power for a pair of tires.


I rate the Surly Larry 3 out of 5 because it does stay under 50 watts per tire at 8 psi / 0.6 bars and outperforms some tires in our tests. Check the fat bike tire overview (overview) to see which tires have a lower rolling resistance.


RATING: 3 / 5
TEST VERDICT:
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