well, basically its a MOTOCROSS 250cc engine with a spread out enduro gearbox...its not really a straight enduro engine, it could shock you,hell 125cc motocross bikes are scary fast seriously, I could beat 600cc fourstroke riders on my old RM125 on the track but if the rider was better than me he'd beat me on either one..., put it this way 125's take off are REALLY shocking, it would be ilke, you'd ride a couple of sloppy laps then get off the bike at the pits and sputter about 'what kind of people ride this thing, its not from this planet' im not joking, even this remark would be an understatement.
Hard core 2 strokes are great fun, Lots of fun but just be prepared for a shock when discovering their narrower, BRUTAL powerbands
for a first time dirt bike, you'd be better with a milder fourstrokes, dont get 400;s ( i know your trail/road bike is a 650) but 400cc CR-F are actually worlds different, trust me. Why dont you try go to a local MX track ask some local riders, for their opinions, and maybe if you're lucky, ask them for a short ride on a CR-F250 now yes that's a 250 four stroke, get a taste of that FIRST, then if theres a WR250 around at the same time and if you're on good terms with the owner of it, ask him too, just compare...
then you'd know what i mean,
im not condescending you, dirt bikes and road bikes are not comparable, my point is as does many experienced motorcyclist/offroad riders woudl tell you that cc ratings doesnt mean shit. Believe me 250s 2 strokes are BIG, like a road 750's sort off....and in saying so would you recommend learners to go and buy a GSXR750? absolutely not., not even a milder VFR750 (i want that)
That's all. WR250 may be cool ( ilike the bike too i actually used to want one i remember i did, actually i want a(im going back to trail riding _id be looking at a Husquvarna WR360).
As for a Yamaha WR250 2 stroke, I'm afraid i doubt its a right bike for you. 200cc actual 2 stroke enduros (which i doubt they make now) would be good, still quite fast just more forgiving and less weight to throw around in tricky manouvering, 4 strokes are tad porkier yes, but in the hillside stall and restarts, its far far easier to get back into action and out of real trouble than you would with a 2 stroke.
to AllDeaf forum. I am not in the least bit interest in Motorbike or motorcycle or whatever. Funny, that you are not interest in the discussion about deaf perspective or Deaf Culture or anything. 
If you are d/Deaf, then it is all right with me here. 
again 
Here comes fall and winter! For those hardcore dirt bikers u know what I mean, mud and better traction. Fewer people at the bike Parks. I recently did valve adjustment on my wr250 f Yamaha and took it to Hollister. Oh man what a difference it made to change the shim on the cam. Now it rips the mtns! Anybody been riding?