The Schwalbe Marathon Racer is the lightest member of the Marathon family and its name suggests this to be a very fast tire. The Marathon Racer has a 67 TPI carcass, SpeedGrip compound, RaceGuard puncture protection and LiteSkin sidewalls. Unlike the Marathon and Marathon Plus, the Racer doesn't have a thick and heavy anti-puncture layer under the tread. On paper, the Racer should have a much lower rolling resistance than both the Marathon and Marathon Plus.
Specified weight of the Marathon Racer is just 465 grams, this makes it a lot lighter than the Marathon which has a specified weight of 730 grams. The biggest savings seem to be in the anti-puncture protection. The Racer uses a double layer of thin nylon fabric instead of the 3 or 5 mm thick latex layer the other Marathon tires use. Natural thinking suggests lower weight = lower rolling resistance... Let's just run the tests and find out if this is true.
|Supplied By||Supplied by Schwalbe|
|New or Used||New|
|Specified Weight||465 grams|
Size and Weight Measurements
|Size and Weight Measurements (Bike Wheel: 622-17C, Pressure: 60 psi / 4 bar)|
|Specified Weight||465 grams|
|Measured Weight||450 grams|
|Measured Width||33 mm|
|Measured Height||32 mm|
|Tread Depth||1.5 mm|
|Total Tire Thickness Center||4.6 mm|
|Total Tire Thickness Sidewall||0.80 mm|
As previously mentioned, specified weight is 465 grams, my sample comes in even lower at 447 grams. The measured width and height is 33 mm and 32 mm respectively. Width and height both come in slightly below the rated size of 35-622.
Tread depth is 1.5 mm, which is less than both the Marathon (2.3 mm) (read review) and Marathon Plus (2.0 mm) (read review), but still reasonable. The Total Tire Thickness Tread measurements clearly show the Racer doesn't use a thick anti-puncture layer. With a total thickness of 4.6 mm, it's a much thinner tire than both the Marathon (7.3 mm) and Marathon Plus (9.0 mm). At 0.8 mm thickness, the sidewalls only have half the thickness of those tires.
Rolling Resistance Test Results
|Rolling Resistance Test Results (Speed: 29 kmh / 18 mph / 8 m/s, Load: 42.5 kg / 417 N)|
|Inner Tube||Conti Tour 28 (170 gr butyl)|
|Rolling Resistance 90 psi / 6 Bar||
|Rolling Resistance 75 psi / 5 Bar||
|Rolling Resistance 60 psi / 4 Bar||
|Rolling Resistance 45 psi / 3 Bar||
|Rolling Resistance 30 psi / 2 Bar||
|Use the formula: RR (watts) = CRR * speed (m/s) * load (N) to calculate rolling resistance at a given speed and load|
Shockingly, rolling resistance of the Marathon Racer is HIGHER than the plain Marathon with 3 mm thick anti-puncture layer and much higher weight. The Racer is also only barely able to outperform the 'flat-less' Marathon Plus. On average, rolling resistance is some 3 - 5 watts higher when compared to the plain Marathon and 0 - 1 watt lower when compared to the Plus.
I'm really disappointed by the performance of the Racer in the rolling resistance test, it's quite misleading to call this tire Racer when it's slower than the plain Marathon. Only providing a lower weight shouldn't justify the name Racer, rolling resistance should at least be on par with the plain Marathon.
Puncture Resistance Test Results
|Puncture Resistance Test Result (higher is better)|
|Puncture Resistance Tread||16|
|Puncture Resistance Sidewall||4|
|Puncture Factor Tread *||74|
|Puncture Factor Sidewall *||3|
|* Puncture Factor = Puncture Resistance * Total Tire Thickness
Puncture Factor provides a more realistic puncture resistance score for touring tires
How does the double layer of thin nylon compare to the to the thicker anti-puncture layers of the Marathon and Marathon Plus? The Racer sets a higher score in the raw puncture resistance test than both those tires. With a score of 16 points, this is 2 points higher than the Marathon and 3 points higher than the Plus. In the sidewall test, the Racer scores 4 points vs 5 points for both the plain and Plus Marathon.
Because both the tread area and sidewall of the Racer are very thin, it doesn't do so well in the Puncture Factor calculation. Puncture Factor Tread comes to 72 points, which is still a decent score. Because the sidewalls only have a thickness of 0.8 mm, the Puncture Factor Sidewall calculation comes down to only 3 points. 3 points is very low, the Racer is the lowest scoring tire in the Puncture Factor Sidewall calculation to date.
After testing the Marathon Racer, it leaves a bad taste. Because this is the 'Racer' version of the Marathon, I expected this tire to outperform the Marathon by at least a couple of watts in the rolling resistance test. An interesting theory could be that the Marathon and Marathon Plus are just too good. Those tires sell a lot more, which means more R&D resources and better materials are available to improve those tires.
If you don't mind the extra weight, just grab a pair of Marathon (GreenGuard) (read review) and have better performance in both the rolling resistance and puncture resistance department. Because the performance of the Schwalbe Marathon Racer is still equal or better than tires from other manufacturers, it gets a Recommended 3/5 rating.