Join Date: Aug 2011
Location: Living in Thailand, but Home is Linden, NC
I'm 5'9" 200. The max weight for the 250R is 375 lbs. The rear shock can handle your weight, but I'd purchase new RACETECH front fork springs to better support your weight. (I did).
If you feel comfortable on the bike, legs not cramped when in the riding position, and you can easily reach the handle bars without being pulled forward to much, you don't want to be resting your upper body on your arms-the handle bars, then buy the bike.
Agreed however that the 650R, might better fit you. But if you are thinking cost, the new Honda CBR 250 might be worth checking out. It will give you a more up-right riding position.
You say you are new to riding, know it's respect of the throttle and respect of your speed that keeps you safe, not the size of the bike. You're a big man, buy a bike that fits you well.