The most common and most likely answer to this crossword clue is the 7 letter word E-BIKES
I've seen this crossword clue in The Guardian
E
-
B
I
K
E
S
Buddy explains!
The straight part
We know that "vehicles" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case vehicles = e-bikes.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 E-BIKES mean?
E-BIKES noun- A bicycle powered by an electric motor.