FYI, I believe the first year for the XR400 was around 1996. Honda made an XR350 for a while, then discontinued it mid-80's I think. So, there was a stretch where you could only get an XR250 or XR600, until the XR400 came out. On old XR200's be wary of mechanical engine noise, the motor doesn't have an automatic cam chain tensioner, and a lot of them didn't get the periodic adjustment they needed. If you don't mind re-building the motor, then you can probably get a great deal on an old XR200, just tell the seller "hear that noise?" Depending on what type of riding around town you're planning on, I'd suggest an 89 or newer XR600, they start easier than the older versions, have tons of torque, and are comfortable going 65 MPH or faster, depending on gearing and tires.
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Hoop
2006 XR650R, the dual sport bike
2004 DL1000, the street bike