The most common and most likely answer to this crossword clue is the 12 letter word SELF-STARTER
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Buddy explains!
The straight part
We know that "No crank, certainly" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case no crank, certainly = self-starter.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does SELF-STARTER mean?
SELF-STARTER noun- A person who shows initiative and resourcefulness.
- A mechanism (usually one operated by electricity, compressed air, a spring, or an explosive gas), attached to an internal-combustion engine, as on an automobile, and used as a means of starting the engine without cranking it by hand.