These unstudded winter tyres have a diameter of 20". They also have a C rating in fuel efficiency, which is in the middle segment.
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180/60ZR17 (75W) Pirelli Diablo Rosso IV 180/60R17 (75W) | Protyre
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Pirelli Diablo Rosso IV ( 180/60 ZR17 TL (75W) Rear wheel, M/C )
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