Daniel Ricciardo says the driveability of the Renault power unit was so poor in the early stages of 2015 it gave him whiplash.
Renault struggled with the driveability and reliability of its power unit in the opening rounds of the season, with Red Bull limited to a best result of sixth place in the opening five races. Explaining just how difficult the car was to drive, Ricciardo says he was physically affected by the power delivery at the start of the year.
"In the first few races power was one thing, but [with] driveability ... I was getting a headache from my head getting whiplash!" Ricciardo told the BBC. "There were a lot of splutters and whatnot going on when I got on the power. That made it nearly impossible to win this year."
Renault improved the driveability of the power unit as the year went on, with Daniil Kvyat and Ricciardo finishing second and third respectively in Hungary. An updated version of the power unit was introduced in Brazil for Ricciardo to use, and while Red Bull was unhappy with its performance, Renault says the upgrade was only "a tiny spec" of its 2016 plans.
Red Bull will continue to be supplied by Renault in 2016, but the team will rebrand the power units as Tag-Heuer as part of a sponsorship deal.
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