Honda's head of F1 project Yusuke Hasegawa is surprised by how few tokens Renault spent on its latest power unit upgrade.

Renault introduced its B-spec power unit in Monaco, with Daniel Ricciardo going on to take pole position for Red Bull. Remi Taffin said the update "includes significant modifications to the combustion system" and delivers an improvement of around 0.5s per lap, with Renault spending just three development tokens on the new power unit.

With Honda pondering its first token spend of the season ahead of the Canadian Grand Prix, when asked if Renault's upgrade shows what is possible without spending a significant amount of tokens, Hasegawa replied: “Right, this is very surprising.

"I wonder, if their update is as rumoured - that they are changing the combustion system - I don’t think they can do it with just three tokens. So I don’t know how they did that."

Asked if he was surprised by the performance of the upgrade in Monaco, Hasegawa replied: “Yeah.

"Of course I am judging it with some rumours so I don’t see the actual number."

Renault itself is hoping to see the "full benefit" of its power unit upgrade at this weekend's Canadian Grand Prix, which is a more power sensitive track compared to Monaco.

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