Scooter starts bogging at full throttle after a while...

[padly1995]

Hello,
My gy6 50cc scooter with drilled exhaust 6gram roller weights, 84 jet, needle on top slot and drilled out restriction tube in air filter, needle removed from auto choke, because it was failing...

starts bogging if i drive at top speed for more than about 1 minute... speed starts to fall and at the end scooter stops running! But if i let the throttle, so speed falls for about 5km/h scooter starts working again!

Another strange thing is that scooter usualy max it out at 50km/h (34mph), but some times (few times a week) in goes around 70km/h AND NOTHING IS RESTRICED SO IT SHOULD MAX IT OUT AROUND 70KM/H EVERY TIME :SS

I already tried jets from 79, to 87, all positions on the needle, with:
air box restriction tube (not getting more than 20km/h +backfiring),
with drilled restriction tube (current state)
and without it (slow acceleration, top speed about the same as with drilled tube)!
I am also sure that there are no leaks anywhere and that air filter and carburator are clean :D


So what can i try else? Thanks for anwsers :D

[blueboy5000]

Your carb is missing the enricher? Unless you plug that passage, you will have a rich condition. Bog then stall at high RPMs is classic rich-condition.

I strongly urge you to get a new carb with a funtional enricher, and then install whatever jet you want.

Unless your bike is more than the stock displacement, I should think it would run best with a 78 to 80 main jet.

The next issue is get one of the these:

http://www.amazon.com/Filter-Moped-Scooter-Motorcycle-110cc/dp/B00AM6JXE6/ref=sr_1_fkmr0_1?ie=UTF8&qid=1400528855&sr=8-1-fkmr0&keywords=gy6+50cc+paper+cone+air+filter

and then some of this:

http://www.amazon.com/Scotch-Electrical-75-Inch-007-Inch-66-Feet/dp/B001AXD0EY/ref=sr_1_7?ie=UTF8&qid=1400528895&sr=8-7&keywords=electrical+tape

Use the tape to cover about 2/3 the surface of the filter, leaving 3/4" exposed. From there, you can add tape to restrict air, or remove tape to increase air.

[blueboy5000]

Also I would say your bike should max at 30 mph (48.2803 KPH) with out serious mods.

My 2008 139qmb has a KOSO variator w 6g sliders, hot coil, "aggressive" CDI, #78 main jet, same air filter I just told you to construct, and it goes 41 MPH (I
70.8111 KPH)gps verified

[padly1995]

Also I would say your bike should max at 30 mph (48.2803 KPH) with out serious mods.

My 2008 139qmb has a KOSO variator w 6g sliders, hot coil, "aggressive" CDI, #78 main jet, same air filter I just told you to construct, and it goes 41 MPH (I
70.8111 KPH)gps verified

Hy thanks for anwser...so is there any other option without enricher to make this carb to work normaly? And do you know if any other carb will fit this engine, like carb from 2 stroke scooter. Because i think that this carb is junk and if i will buy new carb i wont be buying that carb...

About the top speed i dont know... but i had baotian with the same motor before and its top speed was around 65km/h...
And asometimes scooter goes around 70 and on much higher rpm as usual (talking about current scoot)...

Thanks...>D

[padly1995]

Hy thanks for anwser...so is there any other option without enricher to make this carb to work normaly? And do you know if any other carb will fit this engine, like carb from 2 stroke scooter. Because i think that this carb is junk and if i will buy new carb i wont be buying that carb...

About the top speed i dont know... but i had baotian with the same motor before and its top speed was around 65km/h...
And asometimes scooter goes around 70 and on much higher rpm as usual (talking about current scoot)...

Thanks...>D

Today i changed main jet with # 79 and scooter runs much smoother and its more quiet, it just bogs a little from 0 to 5km/h -i just need to set air...
mid acceleration is better, but i didnt get it to top speed jet, im low on fuel :D more info about top speed comes tommrrow or later, if i will ride to gas station today... thanks