alot of the companies have 4 valve liquid cooled dohc 250f 4 stroke quads planned, they are aimed at the youth class, to get rid of all the 300exs and blasters, and give them so more power, and it will also make it less of a jump to the 450 class for them. In terms of a 2 stroke 250, no its not going to happen, not only have companies lost intrest in them, but so has much of the public. As much as any one here hates to admit it, the 450s have come along way from where 4 strokes were 10 years ago, and are now out performing 2 stroke equivilents in many cases(yes i know not all, you can have your drag banshees). But just look at RM125s and 250s, suzuki still makes a 250 because people still like to ride the 2 strokes recreationally, and it still has some good power, but the 125s are simply underpowered to the 250fs, so they stopped production on them. These bikes are made for competitive racing, and if using a 4 stroke engine means winning, then thats what they will use, so they would not make a "MX" 250 quad, since in competive use it would be useless, im really not trying to stir everyone up with this, but ill just give one small fact, and then ill leave this thread(dont worry) on average a 250cc well built 250r set up for mx will put around 50-52hp to the wheels with good porting on race gas, my LTR (which i know everyone here HATES) has simple bolt on mods, a dasa pipe, a pciii fuel controler, and a fuel ATV intake, all of which bring you to a total of around $900, with that set up on a 08 LTR you will get around 51hp to the wheels on an average dyno, throw in a $200 hot cam and you have 53. Just trying to give some facts here to show why the 250s wont be made, not trying to make an argument.
and if someone has to argue the LTRs numbers which they always do, yes i have multiple rear wheel dynojet dyno sheets to prove it