Just for interest I went and did my shopping trips in town on my newly legalized WR250f. It wasn't that comfortable, the 13/50 gearing runs out at 80km, the knobblies howled on the tar but even with knobs on the handling of such a light bike is pretty crisp and it certainly shoots off from the traffic lights so it was a bundle of fun even if I did have to put a padlock on it at every stop. However the thing that could really annoy you is when you are tootling along in traffic with the throttle just open:
JD website:
Yamaha WR250/WR450F Stutter Condition-
This is an ignition problem that Yamaha has designed into the bike to make the motor run cooler at light throttle and medium speeds. The stutter is VERY COMMON, and can sometimes be reduced by disconnecting the TPS electrical lead from your carburetor. The condition is most common on flat roads at light throttle positions, when producing under 10hp at the rear wheel. The stutter is harmless and will not affect the power under acceleration, if it is not too annoying, leave the bike as-is and just ride it. The problem is mostly noticed when riders want to do road riding with their bikes.
You never really notice it off road and even though your brain says ignore it I found it a pest.