The present work follows in the tracks of previous studies investigating the stability of motorcycles. Two principal oscillation modes of motorcycles are the well-known wobble and weave modes. The research in this field started about fifty years ago and showed how different motorcycle parameters influence the stability of the mentioned modes. However, there is sometimes a minor lack in the physical analysis of why a certain parameter influences the stability. The derived knowledge can be complemented by some mechanical momentum correlations. This work aims to ascertain, in depth, the physical phenomena that stand behind the influence of fork bending compliance on the wobble mode and behind the velocity dependence of the weave damping behaviour. After a summary of the relevant work in this field, this paper presents different rigid body simulation models with increasing complexity and discusses the related eigenvalue analysis and time behaviour. With these models, the mentioned modes are explained and the physical phenomena only partly covered by the literature are shown. Finally, the influence of the rider model on weave and wobble is presented.

Liquid-crystalline compounds with a perfluorinated aromatic ring as the mesogenic core and a propylene carbonate unit were prepared and mixed with lithium bis(trifluoro-methanesulfonyl)-imide (LiTFSI). The self-assembly was driven by the interaction of the polar propylene carbonate unit. Thus it is one of the few examples of liquid crystals with only one phenyl group that is able to self-assemble. Small-and Wide angle X-ray scattering (SAXS/WAXS) measurements indicate that the molecules spontaneously formed a smectic phase. Calculation of the Li-salt dissociation from the data obtained by a combination of impedance spectroscopy measurements and diffusion experiments by 7 Li and 19 F pulsed field gradient (PFG) NMR revealed good dissociation properties of the compounds. The complex of (2-Oxo-1,3dioxolan-4-yl)methyl 4-(decyloxy)-2,3,5,6-tetrafluorobenzoate (4b) with LiTFSI exhibited anisotropic conductivity. The conductivity parallel to the smectic orientation was 125 times higher than perpendicular and is one of the best reported for liquid crystals with propylene carbonate fragments. † Electronic supplementary information (ESI) available: DSC diagrams for the mixtures of 4a, 4b and 4c with various amounts of LiTFSI; WAXS/SAXS of 4a and 4b mixed with 10 mol% LiTFSI, ionic conductivity measurements for 4b, 6 and 8 with various amounts of LiTFSI; NMR spectra of all compounds discussed in this paper. See

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