Robert Kubica says Williams must get on top of a “surprise” balance shift which his FW42 encountered during Q1 at the Chinese GP.
Russell edged his more experienced team-mate by 0.028s to maintain his unbeaten run in qualifying, leaving Kubica less than happy with the handling of his car.
“The balance shifted quite a lot and I got completely different balance which I was not expecting, it took me by surprise,” said Kubica.
“I had massive oversteer. We’ve struggled with understeer all weekend. We have to try and understand this as it came.
“[On the] second run the car balance came a bit [more] to the normal side but still nothing like yesterday, we have to understand those shifts, if it is track conditions, also I was first leaving the garage so maybe track conditions improved.
“It’s important we understand else it’s getting a surprise and you don’t know what to expect on next runs.”
Williams is the only constructor not to score a point yet in 2019, and Kubica isn’t expecting that to change this weekend.
“It will be a long race,” he said. “We will have to see how is the car handling, it’s difficult to expect [anything], difficult to know what will happen.
“We are very sensitive to everything, we lack the grip, it’s normal we struggle more than others, it’s definitely a long race for tyres, so we’ll see.”
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