In races on slope beside river these are taken off balance (4,7)

I believe the answer is:

bank charges

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'beside river these are taken off balance' is the definition.
I don't know anything about this answer so I cannot tell whether this works.

'in races on slope' is the wordplay.
'in races' becomes 'charges' (charging is a kind of racing. I am not sure about the 'in' bit.).
'on' is a charade indicator (letters next to each other).
'slope' becomes 'bank' (bank is a kind of slope).
'charges' put after 'bank' is 'BANK CHARGES'.

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I've seen this clue in The Times.

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