I took the snorkel off, put a 165 main in, put the clip to the 4th groove. Then on the exhaust I took the tip out and drill 3mm holes along the spark arrestor so the total area of the holes was greater than the tip pipe. Stock the arrestor holes only total something like 78mm2 whereas the pipe is I think around 224mm2. Starts and warms up better, idles well hot or cold, no flat spots and has XR400 kind of power delivery, just tonnes more of it. All for just a few bucks and no louder than stock.