After the failure of the four-factory protests following Ducati’s use of a swing-arm “tyre-cooling” attachment at the opening round in Qatar, there is now almost a full house of the under-belly scoops.

Aprilia, Suzuki, Honda and KTM had joined to protest the device, with only Yamaha standing back, but even after appeal they were over-ruled.

Now three of them, plus Yamaha, have at least tried a similar device … although in KTM’s case the attachment that appeared in the rain at CotA was said to be only to deflect water, and was not used in the dry.

Aprilia’s and Yamaha’s versions appeared in time for the start of the European season. Only Suzuki has yet to debut one, in spite of urging by rider Alex Rins.

These attachments, which jut forward under the rear of the fairing like a Mr Punch chin, and have up to three louvres contained by flat side-plates, were said by Ducati’s Gigi Dall’Igna to cool the rear tyre by as much as seven degrees. But he admitted there is a secondary aerodynamic downforce of around 500 grams.

The rules forbid any attachments whose primary purpose is aerodynamic. Honda’s version was at first declined, until they claimed it’s primary purpose was to improve swing-arm stiffness.

By Michael Scott

Photos GnG