Unhappy about own performance? Not if wheels get replaced by hybrid (5,4,7)

'unhappy about own performance? not if wheels get replaced' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'by hybrid' is the wordplay.
I cannot quite understand how this works, but
'by' could be 'with' (I've seen this before) and 'with' is present in the answer.
'hybrid' could be 'cross' (I've seen this before) and 'cross' is present in the answer.
The remaining letters 'oneself' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...