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We present 5 GHz global VLBI observations of the two Fanaroff Riley Type Iradio galaxies B2 0836+29 and 3C465 (2335+26). For 3C465 we present also 1.7GHz and 8.4 GHz global VLBI data. In addition VLA observations were used toobtain arsecond resolution continuum and polarization maps at 5 GHz. Bothsources are very asymmetric on the parsec-scale, with a core and a one-sidedjet, aligned with the main arcsecond scale jet. We place a limit on themilliarcsecond jet to counterjet brightness ratio B$_{jet}$/B$_{cjet}$ \gtsim20 and \gtsim 30 for B2 0836+29 and 3C465 respectively. For 3C465 the strongasymmetry holds to the kiloparsec scale. The brightness asymmetry and the ratiobetween the core radio power and total radio power allow us to constrain thejet velocity close to the core and the orientation of the radio structure withrespect to the line of sight. The results suggest that the plasma speed isrelativistic on the parsec scale for both sources, i.e. v$_{jet}$ \gtsim 0.75cfor B2 0836+29 and v$_{jet}$ \gtsim 0.6c for 3C465. While v$_{jet}$ decreasesfrom the parsec to the kiloparsec scale in B2 0836+29, in 3C465 the very highv$_{jet}$ holds all the way to the kiloparsec-scale {\t bright spot}. Ourresults are in agreement with the unification scheme suggestion that FR-I radiogalaxies are the unbeamed poulation of BL-Lac objects. Furthermore, theyreinforce the idea that the central engine in FR-I and FR-II radio galaxiesmust be qualitatively similar. The different radio morphology could then be dueeither to an intrinsically different nuclear power, which affects the torusgeometry or to different conditions in the region beyond the parsec scale,where a significant deceleration in the FR-I jets occurs.Comment: 28 pages, 4 tables, 8 figures all available under request from  tventuri@astbo1.bo.cnr.i

VLBI Observations of a Complete Sample of Radio Galaxies. VI. The Two FR I Radio Galaxies B2 0836+29 and 3C 465