engine hesitating

Hello,

I've been lurking and reading for a little bit now, getting the feel of what I needed to get a used motor running. I got my motor to run now, but I recently took it for a 15 minute straight ride and noticed that it hesitates at high speed. Then once in a while when I slow down (after taking a corner) and try to accelerate again, it hesitates for about a minute, almost seems like it's getting flooded, then picks up and goes again. I have moved the e-clip on the second notch and adjusted the idle so it doesn't stall when stopped. The air filter is clean and no obstruction that I know of to make it run the way it's running. Can anyone help diagnosing this?

thanks in advance

Thank you for the response. I checked the spark plug, the color is whitish gray. I will have to check the float bowl, but if it's a low float setting, do I bend the lever slightly up or down. I don't think I have a float bowl that has a vent, but I will check.

As far as the fuel ventilation, it looks good. The fuel flow seems ok. I do have a fuel filter. The fuel seems to adequately drip down normally from it. The fuel valve is turned on all the way so the fuel flows directly down with no hesitation.

thanks again

ok, I will take a picture of the spark plug, but I think I found the problem. I opened up the area where the float is ( I don't know what's it's called) and noticed that the brass rod that holds the throttle pin in the middle of it was loose. I mean, it fell into the bowl when I remove the screws to separate the bowl from the carburetor. I had screwed this in when I first got the motorbike. I made sure it was tight, but I guess it wasn't tight enough. Anyways, is this normal for it to come loose? What causes it to loosen like that? If it is normal, can I use threadlock to secure this permanently in the future (if it loosens again)? After securing it, I rode it and the hesitation disappeared. I will have to ride it some more and longer to really figure if that is the source of the issue. I only rode it for about 10 minutes tonight.

Ok, so that might be the problem. I would like to take it out for a longer but by the time I get home, it's dark and I don't have lights yet. I will definitely check it out more if/when I get home early enough to ride. Anyways, here's the pic of the spark plug. I was wrong, it's actually more of rusty color (brownish) than whitish gray.

I will update when I go for a longer ride. Thanks everyone for the replies.