Tao Tao 125d carb issues

Pepto · 10-30-2020, 10:00 AM

Hi I’m new to this site I purchased a new Tao Tao 125d atv for my kids 2019 which never ran that good since new it idles perfectly but bogs out from 1/4 throttle to wot since the stock carb is in accessible to adjust I purchased a new ox 20 off Amazon I adjusted the needle all the way down which seemed to help and adjusted the air mixture to 2 turns out from a seated in as a base line but what’s strange is if turn the air screw in which causes the idle to run rough the bog improves but if I make it smooth out it bogs more . ! I’m in the ny area so I don’t believe altitude is an issue . Please help this is making me nuts !

Sponge1971 · 10-30-2020, 11:51 PM

Hi Eh!
I am certainly no expert... I’m just learning how to tune my Tao Raptor 200 ATV... but, it sounds like your pilot jet may be too rich (too big a number). I just watched this excellent video on tuning a Chinese carb, hopefully the link will work...
Or else search for this in Utoob
“ How to tune a carburetor in a GY6 Chinese scooter 150 or 50 cc “
This video shows a diaphragm carb, but the jet theory is where I think you’ll agree with my diagnosis, based on what you have already tried.
Good luck!... I’m suffering with rough idle problems, myself...
Eric

Pepto · 10-31-2020, 01:14 PM

I’ll check it out thank you

dirtbkr188 · 10-31-2020, 01:43 PM

Do you happen to know what sizes the main and pilot jets are in your carb? Also, can you post up a few pics of the carb in question, if you don't mind?

Pepto · 11-09-2020, 10:57 PM

Quote:

Originally Posted by dirtbkr188

Do you happen to know what sizes the main and pilot jets are in your carb? Also, can you post up a few pics of the carb in question, if you don't mind?

carb is pz 20 I’ve taken off the bowl and removed the main and pilot jet and there’s no numbers even the sealed factory carb I drilled out and same thing no markings or numbers ?

Sponge1971 · 04-03-2021, 12:51 PM

ha! what a coincidence... I am *just* dealing with this exact same probelm. (sorry for such late reply... it's been a while)
I just installed a PZ20 into my niece's ATV and its exactly the same. idles fine, bogs terribly if you push fast on the throttle... usually stalls. (it works fine if you ease it up to WOT, though). WOT running is fine.
in no particular order... here is 'stuff':
- I can't seem to find the type of jets for these carbs. Not easily anyways. Up here in the Great White North... we just don't have the 'stuff' available. And, I can't justify tons of shipping/duty dollars for this.
- I found that the main jet is #80. (both in the OEM PZ22 I took off and the PZ20 I installed.). I found a #100 drill, so I drilled out one of the #80 mains and tried it out. Terrible. WOT running was blarfy. So... keep the main at #80, or else go up in small increments, if you must...
- I have recently come to learn that the whole 'bogging' issue is due to the slow/pilot jet being too small/lean. I found that one of the 2 carbs has a #34 pilot jet in it. Again, I have no other jet options, and no drill small enough (I have ordered a drill kit from Amazon...).
PEPTO, the weirdness of 'turning air screw in... improves bog' is because you are forcing the pilot jet to run 'rich'... but, at the expense of idle. The solution is to get a slightly bigger pilot jet (not too big or else you won't be able to 'lean out' the air screw for good idling.)
The final proof for me was: I set the carb for best idle... then I put the choke on about 1/2 way, just where the idle was getting rough (too rich)... blip the throttle and there you go! not perfect response, but w-a-y better than the bogging it does 'normally'
I say we need a #36 or #38 pilot jet (and I'd love to try a #90 main... just becuase)
OH! I forgot... I also discovered that the needle on the PZ20 was adjustable! I moved the clip down 1 spot (opens up the main jet a bit more when throttle is closed = a bit richer mixture all around). Sadly, it wasn't enough. There was no real difference.... but it was late and I had to abandon. Perhaps the solution is to put the clip at the very bottom and see what happens... The ATV is gone for now, so I won't be able to test this out for abit...

miatawnt2b · 04-03-2021, 05:14 PM

Stick an 80 main jet in it. Leave the pilot stock. Needle in center position.

10-30-2020, 11:51 PM	#2
Sponge1971 Join Date: Oct 2020 Location: Oshawa, Ontario, Canada Posts: 13	Hi Eh! I am certainly no expert... I’m just learning how to tune my Tao Raptor 200 ATV... but, it sounds like your pilot jet may be too rich (too big a number). I just watched this excellent video on tuning a Chinese carb, hopefully the link will work... Or else search for this in Utoob “ How to tune a carburetor in a GY6 Chinese scooter 150 or 50 cc “ This video shows a diaphragm carb, but the jet theory is where I think you’ll agree with my diagnosis, based on what you have already tried. Good luck!... I’m suffering with rough idle problems, myself... Eric __________________ Tao Tao Raptor 200 Tao Tao DB 110 (Princess Auto) Mini-Bike Kit
	0

04-03-2021, 12:51 PM	#6
Sponge1971 Join Date: Oct 2020 Location: Oshawa, Ontario, Canada Posts: 13	ha! what a coincidence... I am just dealing with this exact same probelm. (sorry for such late reply... it's been a while) I just installed a PZ20 into my niece's ATV and its exactly the same. idles fine, bogs terribly if you push fast on the throttle... usually stalls. (it works fine if you ease it up to WOT, though). WOT running is fine. in no particular order... here is 'stuff': - I can't seem to find the type of jets for these carbs. Not easily anyways. Up here in the Great White North... we just don't have the 'stuff' available. And, I can't justify tons of shipping/duty dollars for this. - I found that the main jet is #80. (both in the OEM PZ22 I took off and the PZ20 I installed.). I found a #100 drill, so I drilled out one of the #80 mains and tried it out. Terrible. WOT running was blarfy. So... keep the main at #80, or else go up in small increments, if you must... - I have recently come to learn that the whole 'bogging' issue is due to the slow/pilot jet being too small/lean. I found that one of the 2 carbs has a #34 pilot jet in it. Again, I have no other jet options, and no drill small enough (I have ordered a drill kit from Amazon...). PEPTO, the weirdness of 'turning air screw in... improves bog' is because you are forcing the pilot jet to run 'rich'... but, at the expense of idle. The solution is to get a slightly bigger pilot jet (not too big or else you won't be able to 'lean out' the air screw for good idling.) The final proof for me was: I set the carb for best idle... then I put the choke on about 1/2 way, just where the idle was getting rough (too rich)... blip the throttle and there you go! not perfect response, but w-a-y better than the bogging it does 'normally' I say we need a #36 or #38 pilot jet (and I'd love to try a #90 main... just becuase) OH! I forgot... I also discovered that the needle on the PZ20 was adjustable! I moved the clip down 1 spot (opens up the main jet a bit more when throttle is closed = a bit richer mixture all around). Sadly, it wasn't enough. There was no real difference.... but it was late and I had to abandon. Perhaps the solution is to put the clip at the very bottom and see what happens... The ATV is gone for now, so I won't be able to test this out for abit... __________________ Tao Tao Raptor 200 Tao Tao DB 110 (Princess Auto) Mini-Bike Kit
	0

10-30-2020, 10:00 AM	#1
Pepto Join Date: Oct 2020 Posts: 3	Tao Tao 125d carb issues Hi I’m new to this site I purchased a new Tao Tao 125d atv for my kids 2019 which never ran that good since new it idles perfectly but bogs out from 1/4 throttle to wot since the stock carb is in accessible to adjust I purchased a new ox 20 off Amazon I adjusted the needle all the way down which seemed to help and adjusted the air mixture to 2 turns out from a seated in as a base line but what’s strange is if turn the air screw in which causes the idle to run rough the bog improves but if I make it smooth out it bogs more . ! I’m in the ny area so I don’t believe altitude is an issue . Please help this is making me nuts !
	0

10-31-2020, 01:14 PM	#3
Pepto Join Date: Oct 2020 Posts: 3	I’ll check it out thank you
	0

10-31-2020, 01:43 PM	#4
dirtbkr188 Join Date: Aug 2009 Posts: 521	Do you happen to know what sizes the main and pilot jets are in your carb? Also, can you post up a few pics of the carb in question, if you don't mind?
	0

04-03-2021, 05:14 PM	#7
miatawnt2b Join Date: Dec 2020 Posts: 78	Stick an 80 main jet in it. Leave the pilot stock. Needle in center position.
	0