Earlier this year, we tested a 2017 KTM XC 300 from project bike builder Jay Clark. Jay's goal for the build was to make the XC a little more trail friendly. We put the bike through its paces and rode it on everything from wide-open desert-like terrain to tight and technical single-track trails that hadn't been ridden (or maintained) for several years, and were very impressed with how the modified 300 XC performed. Since then Jay has put over 30 more hours tweaking it. The bike ran great on our initial test months before, but Jay—always looking to improve and make his bikes better—swapped out the stock Mikuni carburetor for a Keihin 38mm PWK Airstryker unit from JD Jetting. He brought the bike back out for us to ride again at the 2018 EnduroCross Ride Day at MotoVentures in Anza, California, so we put test rider Allan Brown at the controls of the orange off-road bike to determine how the bike differed with the Keihin 38mm PWK Airstryker installed.