Recent content by Cyrille72FR

My guess is : the later design create a flow closer to the intake side, with better swirl, leading to better efficiency. Pour water in the upper transfer, you'll see how they flow in the chamber (take out the spark plug, so water will go out).

It doesn't create wave, it just low-pass what the noise combustion and exhaust generate. I guess not around it's tuning frequency, where it's free flow, but upper band is a resistive load for the exhaust gas. But it's seems to be really high in frequency to be effective... though I should...

hello, That's not what I meant, I mean when we implement a tube in a can exhaust, it behave as a bass-reflex : the tube is a band-pass. I measured my MS261 exhaust which has a tube, it low-pass around 250Hz. But I should redo the measurement with a "cleaner" protocol.

Hello, I made a simple muffler mod on my 2011 MS261 carb. Opened up the exhaust with a 13mm drill bit. Tuned the carb, runs great. It's my firewood worksaw... Need a rebuild tho, I'll open a post about it. Aluminum color anti-rust paint, supposedly withstanding 600°C after being cooked at...

A chainsaw "can box exhaust" cannot be tuned as well as a true 2 strokes exhaust. But it still act a helmotz resonator : a volume and a tuned exhaust, if there is a tube in exhaust as in 261 (think of a bass-reflex loudspeaker). Increasing the exhaust port surface will somewhen lead to no...

Exactly strato ports don't change the two strokes timing, it just adds a layer of pure air between burnt gas, and mixture.