That engine should pull clean and hard from idle to red line in any gear and if it will not, something is wrong. Having to run at or near red line in order for it to move under its own power is no good and a safety hazard.
Pull fuel line off at carb, put end in a pop bottle, start engine and fuel should freely flow.
Check for vacuum leaks around carb boots.
If no success with above, carbs will have to come off for a teardown, clean and inspection...no getting around it.
There's some acceleration at lower speeds in the higher gears, but not a lot, and second in particular seems jerky below 20. Though I drive my car with a lead foot, so maybe I'm expecting a bit much. Everything I found about this bike said to rev it, and I'm not going much higher than the maximum speeds for the break-in period, I'm certainly not holding the throttle wide open or anything. First seems slow at first, then takes off when it hits about 12, second seems slow and jerky till it hits 25, then it takes off. Even before I started having problems I was starting to wonder if the idle speed was too low. It would take at least 2 minutes of idling with the choke on full for it to stay running when I moved the choke to half, then on half for a minute or so to stay running with the choke off in 50-60 degree weather. After warming up idle still seemed a bit weak, and I'd have to give it some throttle for it to move much in the friction zone. Now with the higher idle speed and premium gas it takes about 30 seconds on full choke to warm up, and there's actually some pull in the friction zone. I am a bit worried that the idle speed might be a bit high though, how do you tell if the idle speed is set right without a tach?
High idle speed is just semi-covering up a problem.
Premium gas will fix nothing.
You are going to have to get down and dirty with a little troubleshooting.
See post #12 to start with the basic and easy first two steps.
As an add, gas should not dribble out in step number 1, maybe with the exception of what is in the fuel line, when the engine is not running.
Have you tried running it with the fuel cap open to make sure you don't have a vacuum lock.??
Tried, doesn't seem to make a difference. I sat in my driveway revving it a few times, after a minute it started to rev without the hesitation, though it still seems to be running a bit rough. However, now when I close the throttle it takes 2-5 seconds to return to idle. The throttle free play and cables seem to be okay, and the throttle snaps closed.
I'm going to say a plugged pilot jet from sitting before you bought it. The dealer more than likely blatently lied to you. Rest assured, stranger things have happened. Mine had a similar problem with "hesitating" when you open the throttle and "hanging high" after it snapped back (see my previous started threads). Except mine had backfiring and power loss too. So maybe you caught this before it got TOO bad.
Agree with BikerBill on the octane. Manual says 87 octane, put 87 in it. Any more is a waste of money.
Also, your fuel economy should only be that low if you accelerate like that EVERY TIME you enter a main road from a side road. Just like a four wheeler, if you keep the RPMs down, the fuel economy will go up.
I'm going to say a plugged pilot jet from sitting before you bought it. The dealer more than likely blatently lied to you. Rest assured, stranger things have happened. Mine had a similar problem with "hesitating" when you open the throttle and "hanging high" after it snapped back (see my previous started threads). Except mine had backfiring and power loss too. So maybe you caught this before it got TOO bad.
Agree with BikerBill on the octane. Manual says 87 octane, put 87 in it. Any more is a waste of money.
Agreed."hanging idle" indicates a lean mixture or plugged pilot jets..
__________________
If at first you do succeed,try not to look surprised!