Rich Carb & I can't get it working - what can I do?

truthfriend7 · 03-11-2008, 06:58 PM

Hey guys, I just got an 05 Panterra 125. It looks pretty new. A kid sold it to me pretty cheap because it wasn't running. He soaked the carb in cleaner overnight and put it back on and it wouldn't work. I've heard that rubber seals can be damaged when this happens. This is the Keihen brand carb. He thought it was a bent float tab.

Anyhow, I put in a new plug checked out the carb and got it running (the butterfly choke was missing so I had to plug the side hole), but the problem is that it runs way too rich and won't idle. Even when warm I can't start it unless I've got the throttle twisted. I've messed with about every combination I can think of between the idle screw and the mixture screw. Right now it runs best with the mixture screw all the way out. I've adjusted the float tab many times, everything else seems to be intact. Even without the air-box it is still very rich with a really dark plug reading. Any ideas as to what I should do? Thanks.

culcune · 03-11-2008, 07:12 PM

I would suggest finding a replacement carb, considering you got the bike cheap. It could end up being a back-up, if you get the original working, but these carbs don't seem like they like too much attention, and not too much seems to interchange with them as far as working on them.

zundapp2 · 03-11-2008, 08:07 PM

Hello truthfriend,

Where is the mixure screw located, engine side or air filter side of carburetor?

1. If on filter side then the screw controls air intake to the idle circuit. Turning screw out increases air supply. With the screw turned "all the way out" the mixture should be quite lean but it is not. There is a possibility that the channel for air to enter has been blocked and should be cleared with a blast of air.

2. There is also reason to believe the float level may be set too high. (Level is determined by the tab which has been bent. You should consult your manual to see if float level specs have been provided). The float arm contacts a "needle" which controls fuel flow from the gas tank. Too much gas and the engine runs rich, too little gas and it is lean. If you have no manual start by adjusting the tab to fully depress the needle into the seat when the float is parallel to the mating surface of the float bowl. Without seeing your carb it is difficult to be more precise.

3. Check the needle and seat to see if they are clean and if the needle can shut off fuel to the float bowl when the the float is gently raised and the tab applys gentle pressure to the needle.

If all else fails send me some carb photos by PM.

truthfriend7 · 03-11-2008, 08:42 PM

Thanks for your replies guys. I've followed all your suggestions except buying a new carb. I might just do that. I've already adjusted the float tab so that the fuel level would be lower and I've checked that part of the carb and it isn't flooding or over filling as far as I can tell.

Do they sell rebuild kits for these carbs?

red2003 · 03-12-2008, 08:58 AM

If the carb has been tampered with that much, just go on eBay and buy a new one. Guys on there are selling them for cheap. I'm sure a new carb will get you up and running.

fatboy250 · 03-12-2008, 09:52 AM

Is this the stock carb? It may be too big for a 125cc...so a new carb would be in order anyway.

Jason

katoranger · 03-12-2008, 10:18 AM

A new carb would be the easiest fix. If he soaked it in a can of carb dip then the rubber portions may have been damaged.

I have seen carbs on ebay for about $10-20. You will want the 125-150cc type carb.

Allen

truthfriend7 · 03-12-2008, 10:54 AM

Well, I purchased a new car on ebay last night. It's a 25mm which I think is the same size as the original. I don't think it had an aftermarket carby on there.

I'm still bothered by the fact that the more I learn about bikes it seems like the less I know about carbs. This carb looks to be in great shape. I guess it's some tiny little thing that I still haven't learned yet. Some small little seal located ?????? Oh well. Thanks for your suggestions guys.

katoranger · 03-12-2008, 12:55 PM

Does the float have a hole in it? It may have been damaged by the soaking process. Otherwise the needle valve seat might be damaged.

Allen

truthfriend7 · 03-12-2008, 10:58 PM

Good point about the float. I didn't think of that. I went out today and the bike fired up and idled just fine. I didn't ride it or anything and the mixture screw is still out, but I found that rather suspicious. Maybe a hot/cold engine thing?

culcune · 03-12-2008, 11:07 PM

I think Bruce of EJCycles recently posted a diagram of a carb. Forgot to mention looking at that.

truthfriend7 · 03-17-2008, 09:28 AM

Well, in case anyone's interested I ordered a different carb, but it wasn't the right kind and wouldn't fit. It should have, but the design was too quirky. So I took the old one and thread sealed the stationary jets, popped out the mixture screw and lo and behold it finally ran too lean! And I couldn't start the engine without first placing my finger over the hole where the mixture screw once was. So I added another spring to the mixture screw to keep it from falling out and just barely put the mixture screw in place.... too rich. So I took the screw and grinded a little groove in it... too rich. Then I ground a big groove into it for air to pass by... still too rich, but slightly better. There's not much much more grinding I can do and still get the mixture screw into place. I've already lowered the float level, & C clip to the max. I just need another way to limit the fuel and/or increase the air flow to lean the mixture. Is there anything I've missed?

liverchip · 03-17-2008, 12:53 PM

Ummm....If you've lowered the c-clip, you've richened the mixture at the needle. Lowering the clip raises the needle allowing more fuel at partial throttle. Raising the clip leans the mixure at partial. As I've heard that some of the carb castings coming out of China are crap and having been soaked with carb cleaner, I would suspect the casting is shot requiring a new carb. Just my 1.5 cents worth.

truthfriend7 · 03-18-2008, 12:14 AM

Oops my bad. I meant to say I lowered the needle. I did more grinding of the mixture screw and got it to where it is ridable. It doesn't idle well and it doesn't have complete full-throttle power, but I'll eventually take everyones advice and buy a new carb.

coleary15 · 03-18-2008, 09:29 PM

my bike is sorta oing the same thing but im not gonna grind the mixture screw but im selling it so if any1 wants it for parts they can talk 2 me but yeah gas is just flowing out the back and i messed with the floats and the main jet but did u try putting the fuel screw in all the way and turning it out 2 1/2 turns out b4 u cut it? it worked 4 a while for me til it came all the way out and i lost it lol

03-11-2008, 06:58 PM	#1
truthfriend7 Join Date: Dec 2007 Location: Florida Posts: 92	Rich Carb & I can't get it working - what can I do? Hey guys, I just got an 05 Panterra 125. It looks pretty new. A kid sold it to me pretty cheap because it wasn't running. He soaked the carb in cleaner overnight and put it back on and it wouldn't work. I've heard that rubber seals can be damaged when this happens. This is the Keihen brand carb. He thought it was a bent float tab. Anyhow, I put in a new plug checked out the carb and got it running (the butterfly choke was missing so I had to plug the side hole), but the problem is that it runs way too rich and won't idle. Even when warm I can't start it unless I've got the throttle twisted. I've messed with about every combination I can think of between the idle screw and the mixture screw. Right now it runs best with the mixture screw all the way out. I've adjusted the float tab many times, everything else seems to be intact. Even without the air-box it is still very rich with a really dark plug reading. Any ideas as to what I should do? Thanks.
	0

03-11-2008, 07:12 PM	#2
culcune Join Date: May 2006 Location: Yuma, Arizona Posts: 9,056	I would suggest finding a replacement carb, considering you got the bike cheap. It could end up being a back-up, if you get the original working, but these carbs don't seem like they like too much attention, and not too much seems to interchange with them as far as working on them. __________________ "They say that life's a carousel, spinning fast you got to ride it well..." TGB Delivery Scooter 150 TMEC 200 Enduro--carcass is sadly rotting in the backyard
	0

03-12-2008, 08:58 AM	#5
red2003 Join Date: Jan 2007 Location: Northern Vermont, USA Posts: 1,271	If the carb has been tampered with that much, just go on eBay and buy a new one. Guys on there are selling them for cheap. I'm sure a new carb will get you up and running. __________________ First Chinabike: 2006 Roketa RSX200E Current Chinabikes: 2023 Titan DLX & 2022 Lifan KP Mini w/ 210cc BRT kit, 22 RWHP!
	0

03-12-2008, 09:52 AM	#6
fatboy250 Join Date: Sep 2006 Location: COLUMBIA, SC Posts: 973	Is this the stock carb? It may be too big for a 125cc...so a new carb would be in order anyway. Jason __________________ 2008 Jonway MC-70-150 2007 Roketa DB-07B (RSM-200E) 2006 Roketa DB-07A (RSX-200E) 1995 Kawasaki Concours (ZG1000)
	0

03-12-2008, 10:18 AM	#7
katoranger Join Date: May 2007 Location: Altamont, Kansas Posts: 15,103	A new carb would be the easiest fix. If he soaked it in a can of carb dip then the rubber portions may have been damaged. I have seen carbs on ebay for about $10-20. You will want the 125-150cc type carb. Allen __________________ You meet the nicest people on a Honda Clone.
	0

03-11-2008, 08:07 PM	#3
zundapp2 Join Date: Dec 2007 Location: Ocala, FL Posts: 49	Hello truthfriend, Where is the mixure screw located, engine side or air filter side of carburetor? 1. If on filter side then the screw controls air intake to the idle circuit. Turning screw out increases air supply. With the screw turned "all the way out" the mixture should be quite lean but it is not. There is a possibility that the channel for air to enter has been blocked and should be cleared with a blast of air. 2. There is also reason to believe the float level may be set too high. (Level is determined by the tab which has been bent. You should consult your manual to see if float level specs have been provided). The float arm contacts a "needle" which controls fuel flow from the gas tank. Too much gas and the engine runs rich, too little gas and it is lean. If you have no manual start by adjusting the tab to fully depress the needle into the seat when the float is parallel to the mating surface of the float bowl. Without seeing your carb it is difficult to be more precise. 3. Check the needle and seat to see if they are clean and if the needle can shut off fuel to the float bowl when the the float is gently raised and the tab applys gentle pressure to the needle. If all else fails send me some carb photos by PM.
	0

03-11-2008, 08:42 PM	#4
truthfriend7 Join Date: Dec 2007 Location: Florida Posts: 92	Thanks for your replies guys. I've followed all your suggestions except buying a new carb. I might just do that. I've already adjusted the float tab so that the fuel level would be lower and I've checked that part of the carb and it isn't flooding or over filling as far as I can tell. Do they sell rebuild kits for these carbs?
	0

03-12-2008, 10:54 AM	#8
truthfriend7 Join Date: Dec 2007 Location: Florida Posts: 92	Well, I purchased a new car on ebay last night. It's a 25mm which I think is the same size as the original. I don't think it had an aftermarket carby on there. I'm still bothered by the fact that the more I learn about bikes it seems like the less I know about carbs. This carb looks to be in great shape. I guess it's some tiny little thing that I still haven't learned yet. Some small little seal located ?????? Oh well. Thanks for your suggestions guys.
	0

03-12-2008, 12:55 PM	#9
katoranger Join Date: May 2007 Location: Altamont, Kansas Posts: 15,103	Does the float have a hole in it? It may have been damaged by the soaking process. Otherwise the needle valve seat might be damaged. Allen __________________ You meet the nicest people on a Honda Clone.
	0

03-12-2008, 10:58 PM	#10
truthfriend7 Join Date: Dec 2007 Location: Florida Posts: 92	Good point about the float. I didn't think of that. I went out today and the bike fired up and idled just fine. I didn't ride it or anything and the mixture screw is still out, but I found that rather suspicious. Maybe a hot/cold engine thing?
	0

03-12-2008, 11:07 PM	#11
culcune Join Date: May 2006 Location: Yuma, Arizona Posts: 9,056	I think Bruce of EJCycles recently posted a diagram of a carb. Forgot to mention looking at that. __________________ "They say that life's a carousel, spinning fast you got to ride it well..." TGB Delivery Scooter 150 TMEC 200 Enduro--carcass is sadly rotting in the backyard
	0

03-17-2008, 09:28 AM	#12
truthfriend7 Join Date: Dec 2007 Location: Florida Posts: 92	Well, in case anyone's interested I ordered a different carb, but it wasn't the right kind and wouldn't fit. It should have, but the design was too quirky. So I took the old one and thread sealed the stationary jets, popped out the mixture screw and lo and behold it finally ran too lean! And I couldn't start the engine without first placing my finger over the hole where the mixture screw once was. So I added another spring to the mixture screw to keep it from falling out and just barely put the mixture screw in place.... too rich. So I took the screw and grinded a little groove in it... too rich. Then I ground a big groove into it for air to pass by... still too rich, but slightly better. There's not much much more grinding I can do and still get the mixture screw into place. I've already lowered the float level, & C clip to the max. I just need another way to limit the fuel and/or increase the air flow to lean the mixture. Is there anything I've missed?
	0

03-17-2008, 12:53 PM	#13
liverchip Join Date: Nov 2006 Location: Mystery Spot Posts: 1,223	Ummm....If you've lowered the c-clip, you've richened the mixture at the needle. Lowering the clip raises the needle allowing more fuel at partial throttle. Raising the clip leans the mixure at partial. As I've heard that some of the carb castings coming out of China are crap and having been soaked with carb cleaner, I would suspect the casting is shot requiring a new carb. Just my 1.5 cents worth. __________________ 2009 XR650L Big Red Pig Tusk bar risers 2007 X-Moto(Jetmoto) GY250 --mods--- 15/40 sprockets UNI Pod Filter 2007 Shineray TMS 200XYi--Betsy Betsy Mods:______________________ Acerbis DHH headlight FMF Powercore pipe Uni Pod Filter
	0

03-18-2008, 12:14 AM	#14
truthfriend7 Join Date: Dec 2007 Location: Florida Posts: 92	Oops my bad. I meant to say I lowered the needle. I did more grinding of the mixture screw and got it to where it is ridable. It doesn't idle well and it doesn't have complete full-throttle power, but I'll eventually take everyones advice and buy a new carb.
	0

03-18-2008, 09:29 PM	#15
coleary15 Join Date: Jan 2008 Posts: 127	my bike is sorta oing the same thing but im not gonna grind the mixture screw but im selling it so if any1 wants it for parts they can talk 2 me but yeah gas is just flowing out the back and i messed with the floats and the main jet but did u try putting the fuel screw in all the way and turning it out 2 1/2 turns out b4 u cut it? it worked 4 a while for me til it came all the way out and i lost it lol
	0