Need some help...

[BradZ_09]

Hi all. Been having a few problems with my pitty...as usual. Well its never been really powerful but only lately has it started doing this. When i havent ridden it for a few days and go 2 start it. For the first 10 or so kicks it doesnt even seem to fire. Then all of a sudden it fires up and starts running.. why? And while im riding. if i give it to much throttle too quickly, which is not very fast anyway. It bogs and splutters and if i keep the throttle at that position it keeps spluttering and just gets lower and lower (revs) then dies. But if i let off the throttle its fine. I have to give it gas so so slowly to let it catch up.. Its never really been this bad.. It feels like more of a problem than just how the engine is. Because its just so so slow. I drag raced my sis. she was running and i just passed her in 3rd.... LOL. But thats also strange. If i giv it 2 much throttle in one gear it does that spluttering thing i told u about. but if i go up gears it keeps gettin faster and doesnt splutter. Until i run outta gears.. HELP

 

[numroe]

Sounds like your air/fuel mix is out. But I assume it once ran ok with the jetting as is, so have you checked these basics:

1) clean and lightly oiled air filter?
2) New spark plug?
3) Fresh fuel in tank?
4) Looks clean in the bottom of the carb bowl?
5) Fuel flows ok from tank out bottom of carb bowl when fuel tap on and bowl screw removed?
6) No air leaks between carb and intake port?
7) Exhaust muffler not blocked for any reason.

If yes on all of the above, then you might have a jetting or CDI problem. Assuming jetting, then:

1) Get it to idle ok via mix screw.
2) Main jet: Ride in a middle gear on flat ground and rolling at mid RPM then turn throttle reasonably fast to full open. Lean = hesitant but it will eventually rev out, if extreme lean then it will bog. Rich = rough and no way it will rev. If extreme rich then it can also bog. But you can detect the difference.
3) Slow jet: Ride in a middle gear and mid RPM then turn throttle reasonably fast to 1/4 open. Lean vs rich is as per (2).
4) Needle: As above but turn throttle to 1/2 to 3/5 open. Adj needle as required.
5) Repeat from step (1) down to fine tune. Because there is overlap in the jets and throttle range.

If you still have no luck, then try a new CDI unit. Not expensive. Also remove your magneto cover and check for a loose magnet and any corrosion in there.

btw: What engine and carb do you have? These days, it's pretty cheap to get a new engine WITH carb.

Good luck.