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This research note presents a comparison of radial velocities between theRAVE DR5 data release with Gaia DR2. RAVE DR5 and Gaia DR2 have 450587 stars incommon. In particular we would like to shed light on a small subset of jointtargets (707 stars) that exhibit a constant velocity offset of +105 km/s or -76km/s, respectively. Overall this comparison confirms the excellent agreementbetween those two data sets. The velocity differences can well be matched withtwo Gaussians with FWHM of 1.2 km/s and 3.6 km/s, respectively. There is asystematic offset of about -0.32 km/s, consistent with the findings in GaiaDR2, who find an offset of -0.29 km/s. The offset is also comparable to theoffset found between Gaia DR2 and other ground-based spectroscopic surveys in asimilar magnitude range, indicative that the source for this offset may atleast partially be related to the radial velocity zeropoint of Gaia DR2. Weidentified 707 stars that exhibit large constant velocity offsets. These casescan be traced to a problem of the reduction pipeline in propagating thewavelength calibration between neighboring fibres near the edges of the fieldplate, in particular for observations done just before fibre repairs, i.e. whenlive fibres were separated by large gaps of broken ones. In 82\%\ of thesecases the offset between RAVE DR5 and Gaia DR2 radial velocity is in the $+105\pm 15$~\kms range. These spectra belong to the first 10 fibres of the fieldplate. Another 3\%\ of the spectra have velocity offset in the $-76 \pm 4$~\kmsrange and were observed with the fibres 148-150. Even though the majority ofthese 707 stars do not exhibit any particularity in the radial velocity, werecommend excluding them from future studies.

A comparison between RAVE DR5 and Gaia DR2 Radial Velocities