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[Bloody]

O.K. so, let's see if I can explain this correctly in words. 2 things are going wrong with it. It will kick over on the 2nd kick and idol perfectly. When I turn the throttle just a little bit it bogs down and cuts off.

Secondly, when I turn the throttle 3/4 to all the way and then let off, it idols up really super high and sounds like the engine is gonna blow up. I turn the key off and engine shut off switch to "off", but the engine won't stop. At this point, I have to turn the throttle all the way and it basically chokes itself out and finally shuts off.

What the hell is wrong with it? Do I need to clean something? Take the carb out?

Please help.........

Bloody

[Mac]

Have you checked your slide action after giving it 3/4 throttle? Your slide might be sticking.  Is your kill switch working at Idle?  You should also be able to kill it by pulling the choke out all the way.

[Sneaky]

Hey,
Congrats on the P.  I love P's. IMO, next to the Honda cub, its the best vehicle ever built.

Per your, Q.
I agree with Mac.  Start with the carb and check for throttle plate play.  It should snap back instantly when you let go of the throttle.  These plate are easily warped when the carb is over torqued.  If the plate does not snap back instant, then disconnect the throttle cable to slide. Pull the slide by hand to recheck it's action.  If it improves then you cable or cable housing is in question.
Other possibility: if the motor is not running (accelerating) properly i.e. bogging or hesitation then consider carb adjustment.  i.e. start with plug chop then adjust jet then air bypass screw.  How does the engine respond with the chock engaged?
Other possibility: check the time; if the motor is stock should be approx 17' retarded (please check manual to verify this setting).
Other possibility: you have an air leak.  usually flyside seal which is an easy replacement. 

Hope this helps.  BTw. what's the bike year? state of tune? history?

[Bloody]

Mac...The slide is moving back and forth fine. And I just replaced the whole throttle cable. The kill switch works at idle, but when the engine revs up real high, it doesn't.

Sneaky....The Throttle plate is snapping back instantly. What's the Plug Chop and where is the air bypass screw? When the choke is engaged, it bogs down.
It's a 1979. It has been sitting since 1987. The guy we bought it from only had it for a month, then got another project bike to work on, so decided to sell this one to us. He said he cleaned out the carb before we bought it, but who knows. It kicks over on the second kick and is in pretty good condition. It also has no fluid leaks, so that's good.


I was thinking of buying a new gasket set and taking the carb apart and cleaning it and changing the gaskets.



Bloody

[Sneaky]

If you're handy.  A carb rebuild is pretty easy.  Just take things apart slowly and take pictures if you can't remember the sequence. 
I would definitely do a rebuild, gaskets, needle and clean out the jets.  Remember to write down the idle & main jet sizes, should be 50-55, and 116-118 I think.... (check the manual).  The air bypass screw is at back of the carb (faces towards rear of bike).  This screw is ofter incorrectly referred to as an air mixture screw.  When you're doing the rebuild... count the number of turns to stop.  Write this down as this is you're current setting.  This screw is a like a fine tuning of additional air (thus air-bypass screw) to the intake system. It will alter your air fuel mixture across the rpm range.  This screw is used only after you've determine the correct idle & main jet size/atomizer.  If you're bike is stock, I'd image the jets are original and may not need changing.
A "plug chop" is a process of road going test of your combustion quality.  Basically find a stretch of road without traffic.  Use 2nd or 3rd gear.  Wind it out for about 5-10 sec and kill then engine right away and coast to a stop with the engine off and of course clutch in. REMEMBER TO KEEP THAT LEFT HAND ON THE CLUTCH AT ALL TIMES.  If the engine seize you will hear pinging/knocking and possible high pitch friction noise right before.  That clutch hand can safe you!!
Once you're back at your garage, pull the plug and read it... what color is it? black, brown, tan, white.
Black= too rich
brown= maybe rich
mocha= good
tan= good to lean
white= too lean

general rule of thumb
Idle jet determines up to 75-80% of you throttle fuel supply
Main jet delivers the remaining 25-20%
Air bypass screw: help with engine quickness to rev up from idle.

If you're 24/24 carb is set correct but the engine still races off throttle, you're likely looking at an air leak some where. I.e. fly side seal. cylinder head.
If the bike has been sitting for 23 yrs, this is very much likely.  Modern gas chew up main gaskets pretty quick, especially "oxygenated" or methanol blend fuel.

Replace the flyside is not hard but you will need a flywheel puller.

Let us know how it goes.

[Bloody]

Thank you Sneaky. I will give all of the above a try. If I have any more questions, beleive me, I will be back asking.

Bloody