Huge bikes in engineering units (10)

I believe the answer is:

megacycles

'engineering units' is the definition.

'huge bikes' is the wordplay.
'huge' becomes 'mega' (I've seen this before).
'bikes' becomes 'cycles' ('cycle' can be a synonym of 'bike').
'mega'+'cycles'='MEGACYCLES'

'in' acts as a link.

I've seen this clue in The Telegraph.

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