[SpudRider]

Your ZS250GS has essentially the same engine as my ZS200GY-2. Zongshen increased engine displacement in your bike by increasing the cylinder bore. Therefore, the bottom end of your engine is identical to mine. I have ridden my ZS200GY-2 for 60,000 miles, so I know this Zongshen engine is reliable.

I recommend the Mikuni main jets for you bike. You can find the information by searching the "Zong Sticky" located at the top of the Dual Sport Forum. I'm sure you will get better engine performance after your carburetor is properly jetted for your altitude, exhaust system, et cetera.

However, I'm going to discourage you from riding your ZS250GS on the freeways of Arizona. I don't think any, 250cc Chinese motorcycle has enough reserve power to travel safely on limited access highways.