diericx.........Saw this in your other thread but thought it might be better to post here as this thread seems more detailed regarding your current repairs:
Originally Posted by Sinical
Adequate back pressure is required on any bike. Without it, the overall power will suffer dramatically. It'll also make the power band while shifting much less smooth. Oftentimes, the power can really suffer in the low gears and then pick up steam at WOT (think drag bike w/straight pipes, but no comparison to street application)
*your reply* : I think this is exactly what's happening to me. I chug picking up speed but sometimes when I manage to get up there it starts to accelerate like crazy (or at least crazy relative to what it is in lower gears). Does that sound right?
Yes, it does sound right to me, but I do need to clarify that I've never owned or worked on a 2-stroke and was answering from experience with 4-strokes. Altho' there may be some similarities between 2 & 4 strokes, the motor dynamics are like different animals. Aussie Steve provided some great insights (that I'm also learning from, same as you) about back pressure/2-strokes and we can see the added element of scavenging during the intake/exhaust phase and how back pressure pertains there.
In an attempt to redeem myself......LOL!.......here's a vid that you might find helpful regarding reed valves: