On line specs show the KLX250 seat height about 1.6" shorter than the KLX300. Does anyone know what is different or how this is achieved?

 

KLX 300 - front travel 11.2", rear 11"
KLX 250 - front travel 10", rear 9.1" (2009 and newer)

 

 

Seat.

 

I'm not sure that's the case. You can superimpose both an '06 300 and 250S on each other and the seats appear identical in size/depth. There are subtle differences between the '06/'07 300 and 250, but most have to do with the attachment of slightly different components like electrical, fuel tank, and rear rack. Curiously, even though the suspension travel numbers are the same, the actual internals are slightly different in spring length, fork rod length, and probably some others. The numbers you're seeing on the seat height probably can't be taken as pure gospel anyway. It could be as simple as a sag difference between the two examples that the data was obtained from.