Engine Trouble Weird jerking and other issues

[BillyBob99]

So I got this cheap kit of amazon and stock, it ran fairly well, expect at mid to full throttle it bogs out, I run 40:1 and raised the clip on notch on the carb needle. I was able to get it running noticeably better but it still bogged out at full throttle, only way I could go faster is to find the perfect throttle point and just ride the powerband. After a few weeks, I bought an expansion pipe and now if I hold the throttle at a consistent speed the whole bike jerks, and if I let off, it still jerks. It only smooths out if your always giving more throttle. And it still bogs at full throttle. I also drilled some holes in the stock carb plastic cover and got a higher compression head with ngk b6hs plug. I have no idea why it’s doing this.

 

[ImpulseRocket]

When you say you raised the clip one notch on the needle, do you mean that you moved the actual clip up a notch, or did you raise the needle a notch? I just want to clarify that distinction before going too far into it.

Now, as far as how it runs after putting that pipe on there, it's not uncommon for a 2 stroke to actually run too rich once a pipe is installed. More of the unburned fuel that used to go out the exhaust gets put back into the cylinder and less of the fuel charge is drawn up from the crankcase thanks to the pressure wave, exactly how a pipe is supposed to work.

There is also the likelihood that you are experiencing a loss of compression. It's a common issue for the head bolts/nuts to loosen during break in, and even after. They are torqued to 144 inch-pounds (12ft-lbs) and it is a good idea to check them on a regular basis, and every time before you ride the bike during the first couple hundred miles.

 

[DAMIEN1307]

Lets also not forget to mention that 40:1 is too lean on oil on a basic China Girl motor from Amazon, too lean...It should be at no less oil than a 32:1 oil fuel mixture AFTER breakin.
If it is still less than 200 miles or so on it, the breakin ratio of oil should be or should have been either 20:1 or 25:1.

 

[BillyBob99]

Yes, I did move the clip up a notch from where it sits stock to lean out since the plug was pretty black when I checked it. And thanks, I'll definitely see if torquing down the bolts will help too.

 

[BillyBob99]

And I'll also change the ratio to 32:1 after this tank of gas, this is what I was going off for the ratio.

 

[DAMIEN1307]

And I'll also change the ratio to 32:1 after this tank of gas, this is what I was going off for the ratio.

He is 100% totally wrong when he says 40:1 cradle to grave...Many a person on this forum destroyed their brand new motors following 'bass ackwards' advice like that found on youtube by the so-called experts.
Many of which were banned and expelled from this forum for insisting on their bad advice even after fellow members blew up their motors following such nonsense advice as this.

Unless your using a Phantom 85 or an Avenger 85, fuel for breakin is mixed in a gas can at 20:1 or 25:1 and then shaken everytime in the gas can before pouring into the tank for proper dispersal for at least the first 150 to 200 miles or so.

32:1 thereafter when breakin is over.

 

[Gordy]

I can't stand most of the guys on YouTube. The only thing I ever took from those guys was styling designs.

 

[Chainlube]

He is 100% totally wrong when he says 40:1 cradle to grave...Many a person on this forum destroyed their brand new motors following 'bass ackwards' advice like that found on youtube by the so-called experts.
Many of which were banned and expelled from this forum for insisting on their bad advice even after fellow members blew up their motors following such nonsense advice as this.

Unless your using a Phantom 85 or an Avenger 85, fuel for breakin is mixed in a gas can at 20:1 or 25:1 and then shaken everytime in the gas can before pouring into the tank for proper dispersal for at least the first 150 to 200 miles or so.

32:1 thereafter when breakin is over.

I put my oil in the jerry can at home and then drive to the filling station. There I put in the correct amount of fuel, seal the container and drive home. On my way home the jerry can gets a vigorous shaking bouncing around in the back of my truck. Am I OK?

 

[Squiddley]

I put my oil in the jerry can at home and then drive to the filling station. There I put in the correct amount of fuel, seal the container and drive home. On my way home the jerry can gets a vigorous shaking bouncing around in the back of my truck. Am I OK?

If on a gravel road or plenty of pot holes.

 

[Chainlube]

If on a gravel road or plenty of pot holes.

Just the way I drive.