I'm mechanically sound, but a bit uneducated here...plus didn't own a dirt bike for 27 yrs. 2013 YZ250, runs perfect. Bike even when cold starts on no more than the 2nd kick, when warm starts on the first kick. Super reliable. 2 weeks ago changed oil, repacked muffler. I don't think this is the issue, but it is a variable. That Sat went to the trails and it wouldn't start. Figured after a bit of kicking it flooded and put a brand new plug in. Old plug wasn't fouled; wasn't fuel soaked, but "barely" wet. Removed the fuel line from carb and let gas drain for a second. Assumption: carb is getting fuel. Figured maybe float stuck. Hit float bowl with screwdriver handle. By then was ready for a break from kicking, friend took over and it started. Ran like a champ the rest of the day - no further probs starting. Yesterday, tough to start again - but not as tough as the first time. Banged on the float bowl again and it started maybe 10 kicks later. Once started, started fine rest of day. Got it home and it wouldn't start - but it did half-ass fire a few times. Only kicked it maybe a dozen times then put it to bed. Thoughts: First thought is float is sticking, but I'm confused on why it would stick/be hard to start cold, then run fine/be easy to start when warm. Seems like now it's tough to start when the engine is cold - even when using the choke. If the float was indeed stuck, why would it run fine but be tough to start. Does engine vacuum come in to play here? I don't have a good grasp of how the carb works - is there a section/portion of the carb that just affects starting - possibly just cold starting? Not sure how much time I'll have today to look in to this, plus tomorrow it's going in for susp work. Thanks.