Dam, I've been riding 2 strokes of various platforms for the past 38 years and it's amazing how you still after so much experience get smacked with a unique issue. Went riding with my daughter yesterday this was just a simple NH state OHRV trail that's just an abandoned rail bed. Fairly straight and about 17 miles long. I fueled up the K5 along with our ATV with only raw gas so I needed to add oil to the K5. I added exactly 2.5 gallons so I added 8 oz of oil right into the tank. In hindsight, what I forgot to do is shake the bike to mix the new oil and gas and that proved to be a big mistake. Upon initially driving down the trail the low speed drivability was horrible, wouldn't idle, real bad surging, and erratic engine rpm's. The engine was loading up, smoking excessively but would clean out upon a hard WOT blast. I initially though I had developed water in the fuel. After about 15 min I started to see some improvement after about a half hour the engine was now running perfect. Pretty sure when I dumped in the oil, it flowed right into the petcock and was blocking fuel flow. I run Klotz R50 and it's a pretty thick oil. I generally always have pre-mix all ready to go but I had no extra fuel jug so I figured when the heck just add oil later. So from now on either pre-mix or add oil very lightly into the fuel and SHAKE !
