While more and more manufacturers now offer a fat bike tire, the Bomboloni is Vittoria's answer to this increasingly popular bike discipline. The Vittoria Bomboloni offers a 120 TPI tubeless-ready casing with a fast rolling alternating center tread and 'automotive inspired' snow-tire tech. Unfortunately, the Bomboloni doesn't use Vittoria's new Graphene (G+) compound but only a simple "Dual-Compound" compound. As expected from a fat bike tire, the Bomboloni is only available with a reinforced TNT casing.
It's a shame the Bomboloni doesn't use the new G+ compound as it's the only compound (at the moment) that can compete with the Schwalbe PaceStar and Continental Black Chili compounds in the off-road category (MTB overview). On top of not using the G+ compound, the Bomboloni also has a very high weight of 1525 grams which is massive especially for a folding bead tire. These two factors don't bode well for the performance in the rolling resistance tests. Let's just run the tests and see how the Bomboloni performs.
|Supplied By||Bought in store|
|New or Used||New|
|Specified Weight||1525 grams|
Size and Weight Measurements
|Size and Weight Measurements (Bike Wheel: 559-65C, Pressure: 16 psi / 1.1 bar)|
|Specified Weight||1525 grams|
|Measured Weight||1506 grams|
|Measured Width Carcass||95 mm|
|Measured Width Tread||99 mm|
|Measured Height||81 mm|
|Measured Knob Height Center||3.1 mm|
|Measured Knob Height Edge||6.5 mm|
|Measured Total Thickness Sidewall||1.40 mm|
|Measured Total Thickness Center (excluding knobs)||2.10 mm|
As previously mentioned, the specified weight of the 26 x 4.00 Bomboloni is 1525 grams; my sample puts 1506 grams on the scale. The maximum width of the casing is 95 mm; the knobs stick out a bit further which results in a maximum tire width of 99 mm. The height of the tire is 81 mm. The size measurements are pretty much spot on for a 26 x 4.00 rated tire.
The knobs in the center of the tire have a height of 3.1 mm which is on the small side when compared to the other fat bike tires. The edge knobs have a height of 6.5 mm which is better than most other fat bike tires. The sidewalls have a thickness of 1.4 mm which is decent as current "gold standard" fat bike tire (Schwalbe Jumbo Jim SnakeSkin) has sidewalls that are a bit thinner at 1.05 mm.
Rolling Resistance Test Results
|Rolling Resistance Test Results (Speed: 29 kmh / 18 mph / 8 m/s, Load: 42.5 kg / 417 N)|
|Inner Tube||Schwalbe SV13J (390 gr)|
|Rolling Resistance 20 psi / 1.4 Bar||
|Rolling Resistance 16 psi / 1.1 Bar||
|Rolling Resistance 12 psi / 0.8 Bar||
|Rolling Resistance 8 psi / 0.6 Bar||
|Use the formula: RR (watts) = CRR * speed (m/s) * load (N) to calculate rolling resistance at a given speed and load|
I already feared the Bomboloni couldn't compete in the rolling resistance test and the test confirmed my suspicions. At the high air pressure of 20 psi / 1.4 bars, rolling resistance comes in at 33.4 watts Vs 23.2 watts for the Schwalbe Jumbo Jim SnakeSkin (read review) -this makes a 10.2 watts power loss. At the lowest (tested) air pressure of 8 psi / 0.6 bars, rolling resistance comes in at 53.9 watts Vs 38.6 watts for the Schwalbe Jumbo Jim -this makes a 15.3 watts power loss.
The 10.2 watts and 15.3 watts power loss (per tire!), when compared to the Schwalbe Jumbo Jim SnakeSkin, is significant when taking into account the already high loss fat bike tires give when compared to "regular" MTB tires. When we compare the Bomboloni to fat bike tires from other brands, it performs anonymous at the bottom of the pack.
Puncture Resistance Test Results
|Puncture Resistance Test Result (higher is better)|
|Puncture Resistance Tread||8|
|Puncture Resistance Sidewall||6|
When a tire that is heavy and also performs poor in the rolling resistance tests, the puncture tests could save it as it might be optimized to prevent punctures as much as possible. Unfortunately, the Bomboloni can't impress in the puncture tests either. With a puncture resistance tread score of 8 points and a puncture resistance sidewall score of 6 points, it performs better than average. Although better than average is good, some tires that have a lower rolling resistance and lower weight are able to outperform the Bomboloni in the puncture tests as well.
The Vittoria Bomboloni performs anonymous and ends up near the bottom of the charts in the rolling resistance tests. When compared to the current "gold standard" fat bike tire, which is the Schwalbe Jumbo Jim SnakeSkin (read review), you'll have to overcome an extra 15 watts of power loss per tire. In the puncture tests, it performs slightly above average but doesn't impress. On top of the high rolling resistance and average puncture resistance, the Bomboloni is a very heavy tire as well. I don't see a reason to recommend this tire.
I hope Vittoria is going to release a fat bike tire that makes use of their new 4C G+ compound that they also use on some of their MTB tires. If they can also get the weight down to competitive levels, they could have a winner. In the meantime, check the fat bike overview page to see which tires perform better on our tests.
VERDICT: Not Recommended