The most members online in one day was 311, 09-22-2008.
*steven205*, 07 YZ, 131w, 180 Decals, 1norcalracer, 265jt, 2haminah, 450Pilot, 952smom, A Noble Production, aaaaaaaaaa, andrewrwc, bailey11, beg919, bernard151, billjensen6, BK227, blake83, Bradshaw344, Brake_Check, bryan303, Bullitt4110, Burnett144s, Butz, cag33, CaliMX, cbrown, CharlieS, Claud, cnromeromx, connelly29, countrykid631, cpg, cranemom, crf250, crfdude86, CURTIS105, d36yzrider, danimal154, danny malfatti, darsey715, dcura671, dirtdigger99x, dirtydrew, disturbedmtb, dkritzer, dmr51, DMZ, dontlookback, dssmith, Dubie, DustinB333, Factoryphoto, Fourty8 Photos, fryboy, gfmoto, honda 381, Honda456, hrdvp, j$855, jjneele, joe, john3x, JohnnyRotten, jordan 42, JSD, kawasakiboy, Kenny199, KMC, kpsuspension, kramer707, kx1984, Larry63r, Livermore, lostinstates, marc177s, mbegell, Mike Tresch, Millerman, mj22, Moco143, Moto Dreams, Moto211, Motodad, motodaddy60, motohead1990, motokid40, MotoPro Graphics, MotoPunk947, Moto_freak88, MX Dad, mx.ryder, mx114, MX4EVER, Mx4fun, MXADDICT, mxaddict392, mxchip, Mxer313, mxmom28, mxrider, MxShockRider829, MX_563, Napa Neil, Nelson74, nick508, NoFear92, NOR CAL 131, NOR*CAL54, norcalcrf170, norcalkid, norcalmoto01, nysurfsf, Oakrider, Old Moto Pro, oldfart, oldmxer, Opio, osulli170, paramotik, pioletti221, posey226, poseyracing, Prozach, pullin racing, rad rider, rbn1357, Rbrown920, redrider617, RickyD, rickywr, Robbie, Scooterv, sean 252, Sean357, sprewitt, squidmcgee, sterken609, terble250, TomMason1968, Top Shelf, tp311, tractionaction, Vet40MX, WatsonMx777, WFO4LIFE, WileE1, wtrskinut, xxxx, yamaha35, yamahauler, yblocmx657, Yepblaze, youstaride, YZF623, yzhooligan

The most posters in one day was 91, 03-26-2007.
952smom, Bullitt4110, Claud, darsey715, Kenny199, NOR*CAL54