We use the known renormalon structure of Bjorken polarised sum rule (BSR) (Gamma) over bar (p-n)(1) (Q(2)) to evaluate the leadingtwist part of that quantity. In addition, we include D = 2 and D = 4 Operator Product Expansion (OPE) terms and fit this expression to available experimental data for inelastic BSR. Since we use perturbative QCD (pQCD) coupling, which fails at low squared spacelike momenta Q(2) less than or similar to 1 GeV2 due to Landau singularities, the fit is performed for Q(2) >= Q(min)(2) where Q(min)(2) approximate to (1.7 +/- 0.3) GeV2. Due to large BSR experimental uncertainties, the extracted value of the pQCD coupling has very large uncertainties, especially when Q(min)(2) is varied. However, when we fix the pQCD coupling to the known world average values, the D = 2 and D = 4 residue parameters can be determined within large but reasonable uncertainties.