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aKaroo3whilestillofferingtheall-important,
albeit slightly more discreet, off-road look.
Intermsofappearance,thefamilyresemblance
iscleartosee.Thesizeofthetreadblockshave
been enlarged, which narrows the transversal
grooves, the ones running from shoulder to
shoulder, producing a tighter, more compact
design. What this does is create a significantly
increased contact patch, or higher land/sea ratio,
resulting in a smoother ride with increased grip,
butthenarrowergrooveiswhyyouwavegoodbye
to that highly effective off-road traction.
The tightly packed blocks have less room to f lex
–sothecontactpatchremainsconstant,helping
grip–andwillinturnremainslightlycooler,
meaning the tyre should also last longer before it
begins to degrade.
Combined with a stiffer carcass, the idea is
to provide quieter, more relaxed high-speed
cruising,whichforthemassesisprobablya
welcome benefit for losing some off-road grip.
Otherthantheobviousvisualdifferences,the
madscientistsatMetzelerhavealsotinkeredwith
thetesttubestoalterthecompoundstructure.METZELER KAROO STREETCarbon black and silica are the two key
ingredients that form the basis of what used to be
rubber in the good old days.
Carbon black provides the strength and
durability, so a high content is used for full-on
knobbies, but its weakness is low temperature and
reduced grip in the wet.
This is where silica comes in. It is a very soft
compound used generously in wet-weather
race tyres, which have masses of wet grip in low
temperatures but the lifespan of a Mayf ly in a
hurricane. In this case a higher silica content
improves real-world road performance.
The tyre was launched in Sicily, which was
fitting since it was developed there and the island
offers a great variety of roads, tracks and surfaces- as well as a huge permanently smouldering
volcano that provided a dramatic backdrop.
The adventure market’s protagonists were our
test beds, meaning we could test the tyre on a
selection of bikes with 19-inch or 21-inch front
wheels to get a good idea of how the tyres behave.
Air temperature was in the mid-20s at sea level,
but we also headed up into the mountains where
The tightly packed blocks have less room to
flex – so the contact patch remains constant
- Big puddles failed to
upset the tyres - A tight block design
provides consistant tread
connection to the road - Wide, shallow blocks
prevent the tread from
moving under load - Extra silica in the
tyre compound provides
improved wet-weather
handling on the road,
especially in cold weather - Metzeler designed the
Karoo Street Expedition
tyre specifically to suit the
growing modern adventure
bike market
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