I continue to be a "leaner slide" ambassador. The slide has a large effect on 0-1/4 throttle smoothness, and affects the burble when riding at steady throttle and the "pop-pop-pop" on deceleration. It takes a #9 slide for me to make my 300s run the way I want them to.
If you're a racer, or don't ride much in that lower throttle range, then you probably don't have a need for it. But so far, I can't "get there" any other way.
I recently rode a couple of TBI bikes and they don't run cleanly in that range, either. I can even hear it on videos that I watch of them. It takes a tune or re-map to get them to run like a clean-running two stroke can.
Your description of "4 stroking when holding it at a set rpm and stuttering when you roll on" is what I have found to go away with a cut slide. Unless it's really severe, my guess is that most people find what you are describing to be normal and expected.
Just IMO, I know there are other perspectives out there. But I don't think the leaner slides have gotten much attention, and I'm not sure why.
BTW in this case, F5 is likely right and you may have something else going on.
Jeff
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'18 GG XC 300
'05 GG DE 300
'01 GG txt 321
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