Carby GT5 GEN 4 80cc: Rich or is this normal?

[EnFlaMEd]

Hey guys. Ive done about 90kms now on my engine running 16:1 ratio and I am wondering if the engine is running as it should. It seems to be progessively opening up but it does struggle up hills and will stall if held at WOT trying to go up a hill and also if held at WOT and then backed completely off. It seems to run from a choppy range with power to a smooth period with power and then into a choppy stage with no power that it sometimes struggles to recover from regardless of throttle input.
The mixture screw is set at 4 1/2 turns as stated in the manual and the engine starts and idles well. Perhaps idles a little fast. The engine will not start if I try to use the choke. So I never touch it. (choke left down)
One thing I have noticed which is why I am asking this is that the exhaust spits out a **** load of oily liquid. The pic below is after the engine has been run for about an hour. Is this amount of **** normal or am I just noticing it more because its basically dumping onto the cranks and frame?

Cheers

 

[pdxrhett]

Sounds like too much fuel is going into the motor - try messing with the mixture screw, maybe a 1/2 more turn might fix it

 

[Shadeslay]

That much oil would be normal for 16:1, the plug looks a little rich. Try going 7oz per gal, which should be fine for break in and may help with your performance issues. You can adjust your needle to a leaner mixture but that will do little for the spray running that rich. Something else you can do is add a copper street 45 or 90 onto the end of the pipe. To aim it down/away from the bike.

Mixture screw? what carb are you using?

 

[danlandberg]

If you are running a stock carb, there is no mixture screw. The screw on the stock carb is a slide adjustment. Try adjusting the needle, move the E clip up one grove away from the pointy end. This will allow more air to fuel mixture (lean it out). The slide and needle work together, so when you throttle up you will get more air to fuel.

 

[EnFlaMEd]

I am running the stock carb so yes it would be the idle screw I was trying to adjust the mixture with which I have since learned
Thanks for the input guys, I will try adjusting the fuel mix and carb after I have run what is left in the tank through.

 

[Junster]

Could you post a pic from the side of the bike and motor? One far enough away to show the whole motor? From the view showing the pedals the muffler seems very close to the bottom bracket. Making me think the motor is mounted leaning way forward. That could make the carb tilted far enough that the float isn't working very well. It may just be the muffler design.

 

[danlandberg]

If your running a 2 stroke. You should have a slide type carb, but not always.(some 2 stroke carbs are butterfly style).If you have a side carb, Have you tried moving the E-clip a notch?

 

[danlandberg]

At high altitude it is some times hard to get it just right for max HP out put! I have been thinking of an in-between type of adjustment.(With out drilling the main jet) Just have not had time to have my transportation to work down. I know the carb parts are small & a pain in the a** to work with, But try different needle settings! (If yours is a slide type carb)!!!! Give it a try,and see what happens.

 

[danlandberg]

Where is the mixture screw on a stock 2 stroke? (48,66,"80"cc)

 

[danlandberg]

Mixture screw??? Where??????????????????

?????

At high altitude it is some times hard to get it just right for max HP out put! I have been thinking of an in-between type of adjustment.(With out drilling the main jet) Just have not had time to have my transportation to work down. I know the carb parts are small & a pain in the a** to work with, But try different needle settings! (If yours is a slide type carb)!!!! Give it a try,and see what happens.

Sounds like too much fuel is going into the motor - try messing with the mixture screw, maybe a 1/2 more turn might fix it