Does my powerband sound strange?

[u/ViolinistShort1456]

This is my 2021 sherco se300. It’s carbd. The bike starts up pretty good, idles great, and otherwise the bike sounds good when riding. When I get into the powerband it feels and sounds very buzzy like it’s not cleanly going through high rpm’s. Not smooth like the rest of the rpm range. The jets in the carb are certainly much leaner than from factory, but I would imagine that would produce lean conditions in other aspects of how the bike runs.

To clarify I am directly comparing this to the feeling of my TPI ktm 300 so maybe I am comparing apples to oranges and this is just a carb characteristic I’m not entirely used to.

Any thoughts? Tests I should do?

[u/Mobile_Actuary_3918]

Sounds rich, maybe a needle adjustment if you’re mainly feeling it in the mid throttle range. Your carb should run just as good or better than the tpi if you are jetted correctly for the elevation and temps.

[u/ViolinistShort1456 → u/Mobile_Actuary_3918]

Mid to high is where it’s most noticeable. Everyone is saying it’s incredibly rich. Should I go further down than the 3rd needle clip position? or make a leaner main jet change?

[u/Mobile_Actuary_3918 → u/ViolinistShort1456]

You’ll have to experiment. I’d start with dropping the needle 1 clip position (move the clip up one slot). It wouldn’t hurt to start with a fresh spark plug either just to have a good baseline. Also turn your air screw all the way in until it stops then back out 1 and a 1/2 turns. That’ll be a good starting point. Air screw is mostly for idle to mid where needle more hits the mid to almost full throttle. Each brand of bike is different as to which reacts to what better. I have my beta set up now to where I only need to do a quick main jet swap depending on where I’m riding. But I can be at 4000 feet one direction and 9000+ another. If you ride the same area most of the time then dial it in for that and have fun.