taotao hellcat idle

tophattitus · 08-06-2019, 11:25 AM

So i purchased a taotao hellcat and i replaced the carb with another pz25 that wasn't tamper proof because of a float issue. Ive tried adjusting both screws on the carburetor and had slight idle change. idle is stuck somewhere between 5500 and 6000rpm's. i also checked the throttle slide and it wasn't installed upside down. at this point I'm really not sure what is causing the issue other then maybe its jetted different. But any advice would be great.

bogieboy · 08-06-2019, 11:28 AM

sounds stupid but, is the slide facing the correct way? I.E. the rounded notch facing the inlet of the carb and not the engine. if thats switched around, it will make a big difference. you should only have a very small gap at the bottom of the slide, anything big will throw the idle off...

tophattitus · 08-06-2019, 11:39 AM

Quote:

Originally Posted by bogieboy

sounds stupid but, is the slide facing the correct way? I.E. the rounded notch facing the inlet of the carb and not the engine. if thats switched around, it will make a big difference. you should only have a very small gap at the bottom of the slide, anything big will throw the idle off...

Yes its fitted the correct way.

scoot newb · 08-06-2019, 03:03 PM

9 Times out of 10 it is the throttle cable.

tophattitus · 08-06-2019, 03:29 PM

Quote:

Originally Posted by scoot newb

9 Times out of 10 it is the throttle cable.

It's not that. The throttle slide is at tje bottom.

bogieboy · 08-06-2019, 03:49 PM

if the slide is all the way down in the carb body, you have a vacuum leak somewhere in the intake. is the gasket on the back side of the carb in place? any open nipples for emmissions stuff on the intake? intake to head gasket in place?

tophattitus · 08-06-2019, 04:34 PM

Quote:

Originally Posted by bogieboy

if the slide is all the way down in the carb body, you have a vacuum leak somewhere in the intake. is the gasket on the back side of the carb in place? any open nipples for emmissions stuff on the intake? intake to head gasket in place?

there is a nipple on the side of the carburetor. tried covering it but it didn't change anything. the original wasn't hooked up to anything. as far as a vacuum leak im gonna take some time searching, weather permitting.

Stretch-N-Poke · 08-06-2019, 07:18 PM

While you are tinkering, take some pics for us. Front, back, left, and right. That way we can look at them and see if anything looks out of place.

benhonda · 08-07-2019, 06:27 PM

it has to be the slide not closed like it should be. if it were just a vacuum leak the rpms could be high but not that high. The carb is allowing alot of fuel and air in.
Either the throttle linkage is messed up, or the slide isnt going all the way down.
With the filter or airbox off, look into the carb throat to see the slide...the gap at the bottom should be pretty small.

tophattitus · 08-08-2019, 12:29 PM

Quote:

Originally Posted by benhonda

it has to be the slide not closed like it should be. if it were just a vacuum leak the rpms could be high but not that high. The carb is allowing alot of fuel and air in.
Either the throttle linkage is messed up, or the slide isnt going all the way down.
With the filter or airbox off, look into the carb throat to see the slide...the gap at the bottom should be pretty small.

As I've stated before, the slide is at the bottom. It has a very tiny opening. I'm past looking for the easiest explanation as I've checked for all of that. The only thing i could think of prior to this is that it has way to big of a jet. And as bogieboy pointed out a vacuum leak is something i haven't checked for yet.

Whisky · 08-08-2019, 02:24 PM

To big of a jet isn't going to make it idle high. my vote is a vacuum leak. Nipply on side of carb is an overflow for a stuck float, needs to stay unplugged.

Hellkitty · 08-08-2019, 07:34 PM

did you check the choke to make sure it opens all the way when the choke is off? I don't remember if those carbs have a butterfly choke or a choke circuit, I replaced my carb with a vm20 before I ever rode it. I know you said you checked all the obvious, but i just thought i would throw it out there anyway.

tophattitus · 08-09-2019, 01:48 AM

Quote:

Originally Posted by Whisky

To big of a jet isn't going to make it idle high. my vote is a vacuum leak. Nipply on side of carb is an overflow for a stuck float, needs to stay unplugged.

Yea i have a feeling you guys are right about the vacuum leak

Quote:

Originally Posted by Hellkitty

did you check the choke to make sure it opens all the way when the choke is off? I don't remember if those carbs have a butterfly choke or a choke circuit, I replaced my carb with a vm20 before I ever rode it. I know you said you checked all the obvious, but i just thought i would throw it out there anyway.

Choke has full range of motion. And yea its a butterfly choke.

tophattitus · 08-09-2019, 01:12 PM

You guys hit the nail on the head. It's a vacuum leak between the carb and the intake manifold. I even tried removing the heat shield between them but there's just the slightest gap that's letting air in at the top.

tophattitus · 08-15-2019, 10:30 PM

So i decided to buy a mikuni vm22 that came with a intake manifold, bolted it on. changed the jet to a 115 and she is running. Al tho i suspect she might be running a little rich. But im just happy to know that she runs again.

08-06-2019, 11:25 AM	#1
tophattitus Join Date: Aug 2019 Posts: 22	taotao hellcat idle So i purchased a taotao hellcat and i replaced the carb with another pz25 that wasn't tamper proof because of a float issue. Ive tried adjusting both screws on the carburetor and had slight idle change. idle is stuck somewhere between 5500 and 6000rpm's. i also checked the throttle slide and it wasn't installed upside down. at this point I'm really not sure what is causing the issue other then maybe its jetted different. But any advice would be great.
	0

08-08-2019, 02:24 PM	#11
Whisky Join Date: Aug 2018 Posts: 286	To big of a jet isn't going to make it idle high. my vote is a vacuum leak. Nipply on side of carb is an overflow for a stuck float, needs to stay unplugged. __________________ 2018 BD125-8-x21rs ZS190/Genuine PE28 Kepspeed GP1 Exhaust Protaper se x110 bars/grips 1/4 MotionPro throttle Kepspeed Braced swingarm Chimera rear hub assy Grom Intergrated tail light Superlite Sprockets 17/32 custom made from Japan Chimera Swing Arm Bolt RK MXZ Chain #420 All Balls wheel bearings Motodynamic fender eliminator Coremoto ss brake lines Composimo 2.5 lower link Grom Calipers-w/ebc pads/rotors Michelin tire 140&120 13x4/13x7 fatties Grom forks Last edited by Whisky; 08-08-2019 at 04:29 PM.
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08-06-2019, 11:28 AM	#2
bogieboy Join Date: May 2013 Location: finger lakes NY Posts: 2,042	sounds stupid but, is the slide facing the correct way? I.E. the rounded notch facing the inlet of the carb and not the engine. if thats switched around, it will make a big difference. you should only have a very small gap at the bottom of the slide, anything big will throw the idle off...
	0

08-06-2019, 03:03 PM	#4
scoot newb Join Date: Sep 2018 Posts: 403	9 Times out of 10 it is the throttle cable.
	0

08-06-2019, 03:49 PM	#6
bogieboy Join Date: May 2013 Location: finger lakes NY Posts: 2,042	if the slide is all the way down in the carb body, you have a vacuum leak somewhere in the intake. is the gasket on the back side of the carb in place? any open nipples for emmissions stuff on the intake? intake to head gasket in place?
	0

08-06-2019, 07:18 PM	#8
Stretch-N-Poke Join Date: Jul 2019 Location: Chattanooga, TN Posts: 18	While you are tinkering, take some pics for us. Front, back, left, and right. That way we can look at them and see if anything looks out of place.
	0

08-07-2019, 06:27 PM	#9
benhonda Join Date: Jun 2019 Posts: 35	it has to be the slide not closed like it should be. if it were just a vacuum leak the rpms could be high but not that high. The carb is allowing alot of fuel and air in. Either the throttle linkage is messed up, or the slide isnt going all the way down. With the filter or airbox off, look into the carb throat to see the slide...the gap at the bottom should be pretty small.
	0

08-08-2019, 07:34 PM	#12
Hellkitty Join Date: Dec 2017 Posts: 216	did you check the choke to make sure it opens all the way when the choke is off? I don't remember if those carbs have a butterfly choke or a choke circuit, I replaced my carb with a vm20 before I ever rode it. I know you said you checked all the obvious, but i just thought i would throw it out there anyway.
	0

08-09-2019, 01:12 PM	#14
tophattitus Join Date: Aug 2019 Posts: 22	You guys hit the nail on the head. It's a vacuum leak between the carb and the intake manifold. I even tried removing the heat shield between them but there's just the slightest gap that's letting air in at the top.
	1

08-15-2019, 10:30 PM	#15
tophattitus Join Date: Aug 2019 Posts: 22	So i decided to buy a mikuni vm22 that came with a intake manifold, bolted it on. changed the jet to a 115 and she is running. Al tho i suspect she might be running a little rich. But im just happy to know that she runs again.
	1