Okay so I am trying to figure out why at high RPMs my motorized 66cc 2 stroke bicycle is bogging down. It seems though as all of these threads start on this topic they all stray away as people get completely distracted by random stuff. At least 25 different blogs Ive seen this topic, but to no answer.
SOOOOO my stock 66cc/80cc 2 stroke w/ NT carb Its bogging at high rpm, full throttle, generally full speed. (Symptoms don't occur while parked with clutch lock on for me)
1- I believe that I've seen a few fairly close answers. The first is to adjust the needle inside of your carburetor if that does not fix it for you.
2- then make sure that you have no restrictive fuel flow from your tank via the tank filter or the inline filter also make sure that you have no air leaks on the carburetor to the motor. If still boggs down. Then try
3- whenever you are topping out the 66cc 2 stroke a ton of vibrations are going nuts on your motor etc. Ive read that the choke can be just lose enough to move to closed or slightly closed in the unison of high rpms, bumps on road, causing temperamental on and off bogging while 3/4-full throttle. Tightening up this screw had helped some people with the nt carb. I have not yet tried it.
4- vibrations can cause the fuel pouring into bowl to froth during full throttle, causing an odd mixture fuel to air while you are wrapping out the motor, and bogging. (This theory just does not seem logical though as fuel pours into fuel bowl and carb way faster than it can be taken......) adjusting float lower may cause fuel leaks but maybe smoother full throttle rpms.
5- this one might make #4 true. Apparently the stock motors clutches plates can be a little lose, or become lose with first couple rides due to heat and warming up. Will still work fine, grab, disengage. Doesn't stick or anything. But it's JUST lose enough to cause an immense vibration at full throttle, top speed, high rpms. This vibration does like a wagon wheel that you spin to fast, and then it violently wobbles too a stop..... But to the motor and whole bike just for a split second, causing a dragging feeling, a bogging also. The bogging could be cause the immense wagon wheel vibrations from clutch, are frothing the fuel, jigging the choke, making carb/ intake leaks.
CONCLUSION.
-Adjust clutch plates and clutch.
-Add rubber to motor mounts/ frame.
- tighten/ tune any possible intake leaks.
- Adjust needle/ float, clean filters.
- make sure exhaust is flush worth no leaks.
