Moped Army

Same ped, 83 QT50. Finally got it all together this warm weekend here in southwest Oklahoma and took it for a 50 mile cruise. Runs great, but still "4 strokes" some. It will cruise 22-24 easily now. But, like what Fred described in his article, if I let off the gas going wide open a little, it will smooth out, accelerate some then, 4 stroke on me again. I got a lot of throttle cable to twist, even though I've adjusted it in the most I can. It only does it when there is no strain on the engine. I mean, if I'm going up a hill, it will purr like a cat. When on level ground, it 4 strokes on me or going down a hill. One thing I've noticed, when going down a hill and this model does not have a governor on it, if I hit about 25 to 30, feels like it's going to vibrate to death.
Do you think the main jet is a tad too big? Not worry about it and have fun with it? Or try and smooth it all out. After reading different posts, seems like most "stock" peds, 49cc engines, 20 to 25 is about all you should expect. Just take my dad's saying "if it ain't broke, don't fix it." Or could I expect more out of it without boring out the cylinders and putting new carb, and 70cc kit in it.
Really happy with it now. Got the fenders painted, put all the plastics back on it, got a battery and all the electrical is working, except the flasher on the blinkers, just do it manually.
What you ya'll do, fellow ped brethren? Assume that all is clean, carb is not clogged or dirty, good fuel flow, new plugs.....etc. etc. I mean, took all the advice from previous posts and applied them.