LO206 Carb Rule - Float Height

Seems strange to me; they don’t allow you to change the jets in the L0206 engines, but they apparently, from what I’ve read, have no rules against taking the carburetor apart and adjusting the float level, a relatively complicated procedure best left to experienced kart racers. LO206, I thought, was supposed to target new and inexperienced Karter’s.

Most commonly a float adjustment is made to compensate for a change in the slide from a jr to senior class, or vice versa.

The 206 generally is not very sensitive to carburation or changes in air density that it necessitates much adjustment. It takes a pretty big swing in air for it to impact performance. Float adjustment is a nuance on these.

So while one can do it, the actual need to do so is generally minimal, especially if you are relatively new to the sport.

For those that want to play, or set to stock by themselves, I believe briggs have a guide for setting the height, drop and there are tools to ensure it’s set correctly.

What I’ve found with the 206 is that there are a lot of things the engine geek amongst us could or would want to do…but our time is better spent on chassis.

There’s over like 2500+ active 206 racers in the US, some of them have experienced engine builders working with them trying to find an advantage… At the same time, at the same race, others will bolt on an out of the box engine and be right there with them.

@Eric_Gunderson I know you’ve worked with two
Stokes and the 206. What’s your experience with carb adjustments?

3 posts were split to a new topic: Adjusting Jet Sizes According to Changes in Air Density

I (personally) find 2 stroke carburetor tuning to be much more difficult than a Briggs!

With that said, the Briggs is very sensitive to air and humidity change. While overall performance and horsepower may not fall off a lot if you’re off slightly, in a class where the box is extremely tight, it doesn’t take much.

Typically, I will with 2 stroke engines listen very carefully to engine builders advice and metrics and adjust and tune accordingly. I am, admittedly, learning constantly different tricks to stay on top of jetting.

With a Briggs, we are constantly checking the plug and reading accordingly. That, and metrics like peak and average rpm, cylinder head temp, are all great metrics to determine how your engine is performing.

On a race weekend, adjusting float height is usually a “sweeping” change I will make. As most of the time the Briggs is wide open compared to a lot of other engines, adjusting the air screw and needle position seems to make the most dramatic difference in performance. Float height makes an even larger change depending on the adjustment of course.

The Briggs carburetor tuning guide is a great tool, I strongly recommend any 206 racer to read and understand it. Beyond that, start at the stock settings, learn how to read a spark plug, and adjust gradually accordingly.

Lastly, I must say I’ve had a much easier time explaining carburetor tuning for a Briggs to racers and having them do their own adjustments than those learning to tune a 2 stroke carburetor. The fact that the jet is stock and remains unchanged doesn’t seem to affect people’s ability to learn to set float height or make other adjustments with a little tutelage.

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