hello everyone, sorry but im sure you have answered all these questions before but i cant seem to find on your site....is there any difference between xp and xr? other then tire size?....is the engine a true copy of dr 200? if so what yrs parts are interchangable? ...what sprockets do you like for highway?...70 mph? does anyone make a larger plastic tank or should i just hunt for dr one? does anyone sell bags or luggage racks for these things? is there any known weak parts or gremlins?