I Give Up

chinaguy · 08-31-2008, 08:13 PM

I give up. I don't know what to check anymore.

About two weeks ago I got the bright idea of fooling around with the carb, just to see if could get it to run even better than it was. I should have left my hands off. Once I moved the needle clip the bike will idle, but at about 3,000 rpms it breaks up and backfires, like an extremely lean condition. I moved the clip to a couple of of different spots and nothing helps. I tried turning the fuel mixture screw all the way in and then trying to adjust it from about 2 1/2 turns out. I checked the plug, checked the gap, tried a new plug. The plug is a little whitish, like it was running too lean. Nothing helps. I don't know anything else to try except take it to the dealer and see if he can fix it. The whole thing p****s me off, because it was running good, and now I have to load it up and take about 25 miles in the back of my truck.

I should add that I took the carb off and cleaned it and the main jet.

Anybody know anything else I could try?

IronFist · 08-31-2008, 08:42 PM

Check your intake and exhaust manifolds for leaks?

Maybe it's not related to the mod at all. Mice in the airbox?

alonzo · 08-31-2008, 08:59 PM

yep, if you did not tighten the carb down to the manifold good enugh it will cause a lean condition, and the leak gets worse as the vacum/engine speed increases.

If the manifold is straight makesure that you carb didn't get fouled up when you had it apart.

forchetto · 08-31-2008, 09:41 PM

Have you removed or modded the airbox?. I don't know the bike details but, if it has a CV type carb, messing with the airbox can end in tears. Ordinary piston-type carbs are not so fussy, but is still best to do your testing with the original airbox in position.

chinaguy · 08-31-2008, 10:10 PM

Sorry. I should have mentioned that it is a slide needle type carb. It doesn't makes any difference if I run the engine with or without the air filter.

alonzo · 08-31-2008, 10:24 PM

did you take the float bowl off?

Isn't 3,000 where the main jet takes over for the idle system? you might just pull the carb back off and take you float bowl off and pull the mainjet and clean it up with a can of carb cleaner.

Jim · 09-01-2008, 02:48 PM

I had water in my gas, it would idle just fine, but if I gave it throttle it would die out, I don't think that's your issue, just putting it out there...

VinceDrake · 09-01-2008, 02:58 PM

Just re-reading the post, I was kinda thinking, maybe somewhere in the process of the carb-work, maybe the fuel supply line got kinked or collapsed? Might be a good idea to trace the supply line, and do a quick flow test....

--Vince

red2003 · 09-01-2008, 03:24 PM

Yup, for sure you got main jet issues. There must be something in there. Take a break and breathe. You will probably have to pull the carb and clean it again. Take ALL the jets right out (un screw) and spray some carb cleaner into each port and make sure it flows out somewhere else in the carb body. Use some compressed air to make certain nothing is blocking the jets. Like stated above, make sure the bolts are all tight, and the o-ring seals are all in good shape so you have no air leaks. Also, make sure you have the choke cable attached correctly so the choke isn't partially on when you think you got it shut off. Make sure you got the needle back in the slide correctly. I'd try one position up from the pointy end and 2 turns out on the fuel screw. You CAN AND WILL figure this out. It's something simple, I am sure. You just gotta plug away at it. It'll come around!

tigertamer · 09-01-2008, 03:29 PM

Another thing to check is the material of your fuel line...Mine was shipped with vacuum hose instead of fuel line 8O

Also, if you're in doubt, you can change the fuel in the tank, just in case you got a bad dose :idea:

Good luck,
Tigertamer

warrior91 · 09-01-2008, 05:47 PM

Quote:

Originally Posted by tigertamer

Another thing to check is the material of your fuel line...Mine was shipped with vacuum hose instead of fuel line 8O

Also, if you're in doubt, you can change the fuel in the tank, just in case you got a bad dose :idea:

Good luck,
Tigertamer

Indeed ,mine as well. It took about 2 weeks of fuel running through before the rubber started splitting/cracking and tearing....

chinaguy · 09-01-2008, 07:52 PM

I took the carb off again today (which is really a PITA) and I cleaned out the jets again. I buttoned everything back up and just took a spin on it, and it's about 80%. It still sputters a little under hard acceleration. I might be able to adjust the fuel mixture screw a little more to get it just right. I'm thinking it was water (or something) in the gas, or dirt in the main jet. The baffles in the tail pipe have come loose again- I already had them welded once - so I will probably get that fixed before I really fine tune the carb.

Thanks to IronFist, alonzo, forchetto, Jim, VinceDrake, red2003, warrior91, and tigertamer for the encouragement and advice!!

IronFist · 09-01-2008, 09:07 PM

You sir are very welcome!

I'm glad to hear it lad. More than I can explain. As my motorcyclye guru says. "I work for appreciation."

I'm sure alonzo, forchetto, Jim, VinceDrake, re2003, warrior91, and tigertamer will say the same.

Red too. I'd vote for red :wink:

The other 20% is reachable. At 100%, the bike may surprize you. 8O

Jim · 09-01-2008, 10:20 PM

Glad to hear it

, the baffles in my gy5 came loose too, but after re welding them it was fine... I considered gutting it and putting it back together empty, but it was fine after the initial repair so I didn't bother... I figured it would wind up with a similar effect as others have achieved by drilling some holes in the end cap, but I don't know for sure...

VinceDrake · 09-01-2008, 10:37 PM

I'm glad to hear you're mobile again, sir!

If nothing else, by the time you're back to 100% you'll be a carb master! (and with these machines, that's probably a very good thing!)

In all seriousness though, it would probably be wise to change out the fuel hoses to something competant. I can't speak for your specific model, but everything I own, and have worked on has the nastiest, cheesi-est crap on them for fuel lines. May a fuel filter would be a good idea too.

But back to the subject at hand-- You're getting there. Patience and perseverence wins every time, and the more you can handle yourself, the lesss you are at the Mercy of the bike shops. At least locally, I've found bike and boat shops really have no idea how carbs work. (Ask me about the local Mercury Marine dealer sometime....)

Best Wishes
--Vince

08-31-2008, 08:13 PM	#1
chinaguy Join Date: Jun 2008 Location: Central Pennsylvania Posts: 125	I Give Up I give up. I don't know what to check anymore. About two weeks ago I got the bright idea of fooling around with the carb, just to see if could get it to run even better than it was. I should have left my hands off. Once I moved the needle clip the bike will idle, but at about 3,000 rpms it breaks up and backfires, like an extremely lean condition. I moved the clip to a couple of of different spots and nothing helps. I tried turning the fuel mixture screw all the way in and then trying to adjust it from about 2 1/2 turns out. I checked the plug, checked the gap, tried a new plug. The plug is a little whitish, like it was running too lean. Nothing helps. I don't know anything else to try except take it to the dealer and see if he can fix it. The whole thing p****s me off, because it was running good, and now I have to load it up and take about 25 miles in the back of my truck. I should add that I took the carb off and cleaned it and the main jet. Anybody know anything else I could try?
	0

08-31-2008, 08:42 PM	#2
IronFist Join Date: Apr 2007 Location: Toronto Ontario Canada Posts: 2,585	Check your intake and exhaust manifolds for leaks? Maybe it's not related to the mod at all. Mice in the airbox? __________________ IronFist ___________________________________ The "chain" of command is used for beating spammers. ___________________________________
	0

08-31-2008, 09:41 PM	#4
forchetto Join Date: Jul 2008 Location: Gijon, Asturias,Northern Spain Posts: 396	Have you removed or modded the airbox?. I don't know the bike details but, if it has a CV type carb, messing with the airbox can end in tears. Ordinary piston-type carbs are not so fussy, but is still best to do your testing with the original airbox in position. __________________ Jincheng Monkey JC50Q-7 (two of them) Skyteam Dax replica ST110-6 (two of them) Zongshen ZS125-43 Qingqi QM200GY-BA Super Motard Yamaha Virago XV1100 Triumph Bonneville SE Qingqi QM110GY PGO Bug rider 250 Buggy
	0

09-01-2008, 02:48 PM	#7
Jim Join Date: Mar 2007 Location: Abbotsford, BC, Canada Posts: 4,880	I had water in my gas, it would idle just fine, but if I gave it throttle it would die out, I don't think that's your issue, just putting it out there... __________________ "Be excellent to each other" "We are all human. Let's start to prove it!"
	0

09-01-2008, 02:58 PM	#8
VinceDrake Join Date: Nov 2007 Location: Southern Saskatchewan Posts: 491	Just re-reading the post, I was kinda thinking, maybe somewhere in the process of the carb-work, maybe the fuel supply line got kinked or collapsed? Might be a good idea to trace the supply line, and do a quick flow test.... --Vince __________________ "Sometimes it is better to say nothing, and let people think you're an idiot, than to open your mouth and prove it."
	0

08-31-2008, 08:59 PM	#3
alonzo Join Date: May 2008 Posts: 527	yep, if you did not tighten the carb down to the manifold good enugh it will cause a lean condition, and the leak gets worse as the vacum/engine speed increases. If the manifold is straight makesure that you carb didn't get fouled up when you had it apart.
	0

08-31-2008, 10:10 PM	#5
chinaguy Join Date: Jun 2008 Location: Central Pennsylvania Posts: 125	Sorry. I should have mentioned that it is a slide needle type carb. It doesn't makes any difference if I run the engine with or without the air filter.
	0

08-31-2008, 10:24 PM	#6
alonzo Join Date: May 2008 Posts: 527	did you take the float bowl off? Isn't 3,000 where the main jet takes over for the idle system? you might just pull the carb back off and take you float bowl off and pull the mainjet and clean it up with a can of carb cleaner.
	0

09-01-2008, 03:24 PM	#9
red2003 Join Date: Jan 2007 Location: Northern Vermont, USA Posts: 1,271	Yup, for sure you got main jet issues. There must be something in there. Take a break and breathe. You will probably have to pull the carb and clean it again. Take ALL the jets right out (un screw) and spray some carb cleaner into each port and make sure it flows out somewhere else in the carb body. Use some compressed air to make certain nothing is blocking the jets. Like stated above, make sure the bolts are all tight, and the o-ring seals are all in good shape so you have no air leaks. Also, make sure you have the choke cable attached correctly so the choke isn't partially on when you think you got it shut off. Make sure you got the needle back in the slide correctly. I'd try one position up from the pointy end and 2 turns out on the fuel screw. You CAN AND WILL figure this out. It's something simple, I am sure. You just gotta plug away at it. It'll come around! __________________ First Chinabike: 2006 Roketa RSX200E Current Chinabikes: 2023 Titan DLX & 2022 Lifan KP Mini w/ 210cc BRT kit, 22 RWHP!
	0

09-01-2008, 03:29 PM	#10
tigertamer Join Date: Jul 2008 Location: Wheeling, West Virginia Posts: 683	Another thing to check is the material of your fuel line...Mine was shipped with vacuum hose instead of fuel line 8O Also, if you're in doubt, you can change the fuel in the tank, just in case you got a bad dose :idea: Good luck, Tigertamer __________________ 07 H-D XL883C 06 LF 200GY-5 Yin and Yang CAUTION Obey The Traffic Regulation. Always Wear a Helmet. Don't Ride After Drinking Wine. Before Operation, Read The Owners Manual Carefully.
	0

09-01-2008, 07:52 PM	#12
chinaguy Join Date: Jun 2008 Location: Central Pennsylvania Posts: 125	I took the carb off again today (which is really a PITA) and I cleaned out the jets again. I buttoned everything back up and just took a spin on it, and it's about 80%. It still sputters a little under hard acceleration. I might be able to adjust the fuel mixture screw a little more to get it just right. I'm thinking it was water (or something) in the gas, or dirt in the main jet. The baffles in the tail pipe have come loose again- I already had them welded once - so I will probably get that fixed before I really fine tune the carb. Thanks to IronFist, alonzo, forchetto, Jim, VinceDrake, red2003, warrior91, and tigertamer for the encouragement and advice!!
	0

09-01-2008, 09:07 PM	#13
IronFist Join Date: Apr 2007 Location: Toronto Ontario Canada Posts: 2,585	You sir are very welcome! I'm glad to hear it lad. More than I can explain. As my motorcyclye guru says. "I work for appreciation." I'm sure alonzo, forchetto, Jim, VinceDrake, re2003, warrior91, and tigertamer will say the same. Red too. I'd vote for red :wink: The other 20% is reachable. At 100%, the bike may surprize you. 8O __________________ IronFist ___________________________________ The "chain" of command is used for beating spammers. ___________________________________
	0

09-01-2008, 10:20 PM	#14
Jim Join Date: Mar 2007 Location: Abbotsford, BC, Canada Posts: 4,880	Glad to hear it , the baffles in my gy5 came loose too, but after re welding them it was fine... I considered gutting it and putting it back together empty, but it was fine after the initial repair so I didn't bother... I figured it would wind up with a similar effect as others have achieved by drilling some holes in the end cap, but I don't know for sure... __________________ "Be excellent to each other" "We are all human. Let's start to prove it!"
	0

09-01-2008, 10:37 PM	#15
VinceDrake Join Date: Nov 2007 Location: Southern Saskatchewan Posts: 491	I'm glad to hear you're mobile again, sir! If nothing else, by the time you're back to 100% you'll be a carb master! (and with these machines, that's probably a very good thing!) In all seriousness though, it would probably be wise to change out the fuel hoses to something competant. I can't speak for your specific model, but everything I own, and have worked on has the nastiest, cheesi-est crap on them for fuel lines. May a fuel filter would be a good idea too. But back to the subject at hand-- You're getting there. Patience and perseverence wins every time, and the more you can handle yourself, the lesss you are at the Mercy of the bike shops. At least locally, I've found bike and boat shops really have no idea how carbs work. (Ask me about the local Mercury Marine dealer sometime....) Best Wishes --Vince __________________ "Sometimes it is better to say nothing, and let people think you're an idiot, than to open your mouth and prove it."
	0

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