As hes decided on tracks, thats not a biggy.

If you are considering entering Robot Wars, rather than Battlebots, you must keep to the metric weight limit of 100Kg for wheelers / 200Kg for walkers). I believe that Battlebots and spin-off events have limits of 220lbs / 440lbs. I believe Battlebots used to have a very, very generous size limit that prevented robots being too big to enter the arena, but I have no idea what the limit might be!

If you havent already found it, the BB tech forum at http://forums.delphiforums.com/n/main.asp?webtag=BattleBot_Tech&nav=start&prettyurl =%2FBattleBot%5FTechhttp://forums.delphiforums.com/n/mai...v=start&pretty url=%2FBattleBot%5FTech deserves a visit.