This is a repeat rant, do pardon, but I hope it will help further the decline of the frenetic noise and smoke that comes with the cultural phenom of the banshee clean-out of two strokes. Whatever riders want to do to their bikes is their own business. Trials bikes are way tough so wringing a bike's neck at a million rpm unloaded may hurt nothing at all, but I find the resulting noise and smoke mildly irritating. Please feel free to disagree and challenge the technical merits of my thoughts. The admonition to repeat clean-out as some always rule of thumb, even by great riders, is in parts a self-perpetuating cultural phenom. Lacking may be a deeper understanding of air-fuel metering with respect to loading. The clean-out can create a false feedback loop that's I think maybe falling out of cultural favor, slowly, like running no idle as brakes did (think vintage bikes with little in the way of brakes). Rrringggdingdingding!blubbluh? Who crashed! Oh... it's just a clean-out.... Carbureted two strokes are jetted for various states of loading in a compromise and there are no sophisticated sensors and thousands of lines of code as with FI bikes. In some conditionals carbs don't meter well for the conditions. That they can meter well for what matter is what counts, so I prefer them for simplicity. Free revving a bike with only crank inertia loading, with the slide way up on the needle taper can cause 4 stroking on the way up to a million rpm. It's a Newtonian thing of equal reaction to an action. Fueling versus loading. The richness and smoke during the Rrrring and dingdingding phases can be misleading. The default over-rich stock main jets add - a little - to the unhelpful feedback, which is one reason I emphasize not sticking with stock main jets. Add altitude to stock main jets and the negative effects increase. Reasonably well-jetted two strokes that are not over oiled and don't have other things wrong do not need clean-outs after warm-up! If yours does, and won't rev all the way until you do, please don't consider that as normal. The only clean-out that more ideally should needed is coughing up of oil 'lungers' during loaded warm-up. A 2 stroke bike has sat one or more days will collected some oil in the bottom of the crank space. Since switching years ago to better premix oil, in my case Maxima Formula K2 full synthetic from a cheaper oil, I noticed notably fewer 'lungers' coughed up at warm-up. It's now like every fourth warm-up that I'll get a one-second hocker coming up, but that's it. I don't know the petrochemistry of why there is a difference. Maybe some of you do. My warm-up routine is to start the bike on choke for ~5 seconds, click the choke lock off, then pulse the choke at any bogging - no more than 10 seconds long unless it's very cold. TI gently ride around 20 or so more seconds to warm the top end. Then I click it up into third while creeping along, accelerating WFO for a few seconds to vacuum out the 'green stuff.' Done! Bidding a dieu to the cleanout!