Since their relaunch in 2008, ONZA Tires have cemented their position on the marketing after developing certain notably well-profiled tyres. But considering the advanced state of technology within the cycling industry, and the ever harder and faster races, a good profile alone isn’t sufficient, as we consistently demand a higher performance from the rubber compound too. Duly noted, ONZA have spent the past four years developing their GRP40 compound, a specific rubber compound for enduro, freeride and downhillers that is said to offer above-average grip and damping.

CITIUS, IBEX und GREINA kommen in dem neuen VISCO GRP40 Compound.
CITIUS, IBEX and GREINA will come with the new VISCO GRP40 compound.

ONZA spent a full four years analysing, developing and testing the rubbers. After getting the competent team at the VISCO Lab GmbH on board, they succeeded in developing a genuine gravity-orientated single compound tyre with the eponymous 40a – with the figure denoting the hardness of tyres, which is measured in Shore A. When James Doerfling participated in the 2013 Red Bull Rampage on these pre-production tyres and their exciting new compound, their performance stunned him. So they’re clearly something we should be excited about.

Der Direktvergleich zum Anfassen.
Feel the noticeable differences.

ONZA rubber compounds: an overview

RC2 55a – Racing Compound 55a/65a

55a/65a dual compound for the best traction, combined with low rolling resistance and extraordinary durability.
Usage: Cross country, all mountain, enduro, freeride, downhill training

RC2 45a – Racing Compound 45a/55a

The soft 45a/55a dual compound delivers great grip, excellent cornering and a long lifespan.
Usage: All mountain, enduro racing, freeride, downhill racing

GRP40 – VISCO Compound GRP40

High performance GRIP 40 compound with particularly great damping control, a VISCO polymer structure that has been specifically developed for gravity-style riding, offering fantastic grip in filthy, wet and muddy conditions.
Usage: Enduro racing, freeride, downhill racing

Das grüne Label leitet sich vom Entwicklungspartner VISCO her.
The little green label is courtesy of VISCO who collaborated in developing the tyres.

These new ONZA tyres with the GPR40 compound will be available from the end of May 2015.

Words: Andreas Maschke Fotos: Christoph Bayer

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About the author

Aaron Steinke

Aaron was our first employee and actively helped make our company what it is today, significantly shaping the look and direction of our various magazines. Aaron has been pursuing his own projects since mid-2020 but he continues to advise and support us on issues of marketing and technology. For many years, you would usually have found Aaron at casual enduro races, but increasingly you'll find him riding his road bike – long live freedom on two wheels!