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Observational pre-cursors of large solar flares provide a basis for futureoperational systems for forecasting. Here, we study the evolution of thenormalized emergence (EM), shearing (SH) and total (T) magnetic helicity fluxcomponents for 14 flaring with at least one X-class flare) and 14 non-flaring($<$ M5-class flares) active regions (ARs) using the Spaceweather HelioseismicMagnetic Imager Active Region Patches vector magnetic field data. Each of theselected ARs contain a $\delta$-type spot. The three helicity components ofthese ARs were analyzed using wavelet analysis. Localised peaks of the waveletpower spectrum (WPS) were identified and statistically investigated. We findthat: i) the probability density function of the identified WPS peaks for allthe EM, SH and T profiles can be fitted with a set of Gaussian functionscentered at distinct periods between $\sim$ 3 to 20 hours. ii) There is anoticeable difference in the distribution of periods found in the EM profilesbetween the flaring and non-flaring ARs, while no significant difference isfound in the SH and T profiles. iii) In flaring ARs, the distributions of theshorter EM/SH/T periods ($<$ 10 hrs) split up into two groups after flares,while the longer periods ($>$ 10 hrs) do not change. iv) When the EMperiodicity does not contain harmonics, the ARs do not host a large energeticflare. Finally, v) significant power at long periods ($\sim$ 20 hour) in the Tand EM components may serve as pre-cursor for large energetic flares.

On the differences in the periodic behaviour of magnetic helicity flux in flaring active regions with and without X-class events