Dortmund take on the Liga giants in Madrid in the first leg of their quarter-final tie on Wednesday, with Dortmund not boasting a positive record prior to their European games this season.
European clashes with Napoli and Marseille as well as both legs against Zenit have all been preceded by league defeats.
With Dortmund still in the running for second place in the Bundesliga, Klopp says all focus is on Saturday's trip to Stuttgart.
"The defeats had different reasons, but they had nothing to do with the Champions League. We are so very critical of ourselves but it was never a lack of readiness," he told Bild.
"We just often had small fluctuations in shape.
"Even now, for the guys and for me, Real is far away. The Champions League is not a topic in the dressing room."
Klopp added he is keen to put an end to Dortmund's run of poor results before Champions League games at the Mercedes-Benz Arena.
Dortmund beat Stuttgart 6-1 in this season's reverse fixture and can take a big step towards securing an automatic Champions League spot this weekend.
"It would be all right if we could finish that (run) with a win in Stuttgart and provide proof that it has nothing to do with the next big game," he added.
