I bought a new Qlink XF200 from Napalm Motorsports in Austin, Texas. I did not receive an owners manual (although I was promised one and am waiting on delivery of the manual). The bike will not idle, unless the choke is kept approx. 3/4 choked, even after fully up to operational temperature. The carb is described as non-adjustable. I talked with the guys at Napalm and they say the carb has an idle mixture adjustment. The idle speed set screw has been adjusted to its full fastest-possible-idle setting and it still dies when coming to a stop, unless you set the choke to keep it idling at approx. 4000 RPMs. I have not found any info yet on how to tune this carb (or if it will void the warranty if it is tuned). The altitude here in west texas is about 3300 feet above sea level and humidity is very low most of the time. It needs more fuel and my concern is that the engine is being starved for fuel, which will ultimately scorch the piston cylinder. Top speed at just under redline, in high gear, is about 65 miles per hour. Other than that one issue with the carb, the bike is worth the purchase price. I´ve ridden hondas and yamahas all my life so I´m used to a good smooth running engine.