How's this plug look? Lean? Okay?

katoranger · 06-29-2007, 09:29 PM

Picture is not the best, but the color on the stock plug was a light tan to a grey which indicates to me a slightly lean condition.

I was hearing some popping on decel. I remove the carb and raised the needle one notch. I still have one to go if I need it. I also installed an NGK plug too.

The bike runs even better and has alot more low end power and no more popping.

I found the idle adjustment, but not the air/fuel adjustment. I adjusted the idle some.

Allen

tzrider · 06-29-2007, 10:16 PM

It looks new.

To "read" the plug, you have to look down at the base area of the insulator for color. Also, how far up the ground pole the tan is vs the brown, and look for specks, flecks of aluminum on the insulator if you're worried about detonation (I'm a two stroke guy, okay?

) It's somewhat of an art, but I can't tell you squat from that pic. In fact, when I'm lookin' at a plug, I like to have my magnifying glass with me and stand in good light where I can see down into the plug.

If the ground pole (the part that comes out off the body of the plug) is white all the way and the insulator is white to the base, you're way lean. I like the ground pole to be dark to tan up to about half its length and the insulator to have a darkish tan color to it. That way, I'm assured I'm not too lean. Again, on two stroke race bikes, lean means death and/or severe pain.

Talking seizure here and it normally happens at the end of the straight at Texas World Speedway where you're running about 175 mph full lean angle draggin' the knee diving into T1 as you chop the throttle. That way, the evil seizure monster can do maximum damage. Four strokes and mildly tuned ones at that are WAY more forgiving. Still, you don't want it running too lean for too long. You can burn valve seats and such that ain't cool to do.

ob1 · 06-29-2007, 10:50 PM

Looks lean.

Savage · 06-29-2007, 10:52 PM

Does the bike fire right up and idle the 1st time now?
Mine has ever since I went 2 notches and adjusted the mixture.
Did the muffler prior to and conical air filter after.

katoranger · 06-30-2007, 07:00 AM

I was thinking it was lean looking too. I have always been told to read it based on the electrode which in the picture looks lighter than an is. It is a bit more tan. I was going by those guides you find in the back of chilton manuals.

Since I have the stock exhuast and airbox yet I only went one notch to try it first.

The bike starts easily and idles fine. It is alittle colder this morning and I will be leaving for work in a few minutes. I will see how it reacts.

Allen

tzrider · 06-30-2007, 09:20 AM

It could be jetted fine in the idle/pilots and be way lean on top where it normally runs on the highway, the main jet. Do you know how to take a plug chop? This is the only way to read the main jetting. You run it up in a tall gear, 3rd or so maybe, as tall as there's room for where you're taking the chop. Run it at high speed, WFO high rpm, then chop the throttle, pull in the clutch, and hit the kill switch all at the same time and coast to a stop, pull plug, read. This is SOP for race bikes and pretty important on these little bikes that are run out on the highway close to their peak. This is where they live, not on the pilot jet.

red2003 · 06-30-2007, 12:20 PM

tzrider is spot on. Do what he says and then look at the plug. Should be tan on the insulator (the white part under the electrode tip). I am sure it is lean, they all are. If so the proper fix is a larger main jet, or ream out the stocker like I did. Let me konw if you need more info on how to do it.

katoranger · 06-30-2007, 09:15 PM

I understand the plug chop, but have never done one. I am just getting into singles and dirt bikes.

I understand the principles, but my hands on experience is not much. I have never jetted a carb. My bike has the stock airbox and exhaust with no mods.

I plan to keep the airbox, just like it is and change the exhaust to one with a spark arrester that will probably also flow more.

I don't see needing to much of a jet change.

I understand that by raising the needle up it richens the fuel mixture. Is it only at idle and low speed? The main jet is for higher speed?

Allen

red2003 · 06-30-2007, 10:21 PM

Yes, the needle and fuel screw only control idle through mid range throttle position. If you don't plan any airbox mods, you should be fine with the stock main jet. Fatboy 250 has like 8000 miles on his Roketa with a pod filter, drilled exhaust and a totally stock carb. If you have gotten rid of the decelleration pop, and it starts and runs well, you're all set. Run it!!!

AZ200cc · 07-01-2007, 12:38 AM

Ok Red I have a question, My bike starts well as long as I do not touch the throttle..But I do apply the choke. It has some popping when I let off and gear down. I am at almost 7000 ft above sea level..Do I have to jet the carb or will dropping the needle cure any of these problems? You really seem to have a good amount of knowledge.....Any help would be appreciated.

katoranger · 07-01-2007, 08:56 AM

Thanks Red, I think I have it set where it needs to be right now. The little bit of popping is gone and it starts easily and idles fine.

I will be keeping the stock airbox since I plan to offroad it and I don't want to risk getting water and sand in the engine.

AZ200 you may need to increase you jet size due to your elevation. I am only about 1100ft.

Allen

AZ200cc · 07-01-2007, 11:47 AM

Thanks Kato

katoranger · 07-01-2007, 12:02 PM

Your welcome. Red may be able to suggest a starting point.

I have never changed jets.

Allen

AZ200cc · 07-01-2007, 12:10 PM

I work on cars...And thats it. I have had a lot of bikes and can fix basic stuff. But this is over my head..And I know I will screw it up without good advice

IronFist · 07-01-2007, 04:09 PM

Sometimes at high revs my bike stutters, but only when I'm really slamming the throttle. When I roll the throttle it never happens. Air fuel has to stay rich or it coughs when I rev from idle speed. Idle set high to keep from stalling because it is rich at idle. Muffler is drilled, cone filter, iridium plug. I find that the iridium plug is harder to read. I did the throttle chop. Lean at rpm, rich at idle. Need to rejet, not a lot, just a little. I'd be able to back off on the air fuel screw a bit and reduce the idle as well. But I could be totally wrong.

N2r.

06-29-2007, 09:29 PM	#1
katoranger Join Date: May 2007 Location: Altamont, Kansas Posts: 15,103	How's this plug look? Lean? Okay? Picture is not the best, but the color on the stock plug was a light tan to a grey which indicates to me a slightly lean condition. I was hearing some popping on decel. I remove the carb and raised the needle one notch. I still have one to go if I need it. I also installed an NGK plug too. The bike runs even better and has alot more low end power and no more popping. I found the idle adjustment, but not the air/fuel adjustment. I adjusted the idle some. Allen __________________ You meet the nicest people on a Honda Clone.
	0

06-30-2007, 07:00 AM	#5
katoranger Join Date: May 2007 Location: Altamont, Kansas Posts: 15,103	I was thinking it was lean looking too. I have always been told to read it based on the electrode which in the picture looks lighter than an is. It is a bit more tan. I was going by those guides you find in the back of chilton manuals. Since I have the stock exhuast and airbox yet I only went one notch to try it first. The bike starts easily and idles fine. It is alittle colder this morning and I will be leaving for work in a few minutes. I will see how it reacts. Allen __________________ You meet the nicest people on a Honda Clone.
	0

06-30-2007, 12:20 PM	#7
red2003 Join Date: Jan 2007 Location: Northern Vermont, USA Posts: 1,271	tzrider is spot on. Do what he says and then look at the plug. Should be tan on the insulator (the white part under the electrode tip). I am sure it is lean, they all are. If so the proper fix is a larger main jet, or ream out the stocker like I did. Let me konw if you need more info on how to do it. __________________ First Chinabike: 2006 Roketa RSX200E Current Chinabikes: 2023 Titan DLX & 2022 Lifan KP Mini w/ 210cc BRT kit, 22 RWHP!
	0

06-30-2007, 09:15 PM	#8
katoranger Join Date: May 2007 Location: Altamont, Kansas Posts: 15,103	I understand the plug chop, but have never done one. I am just getting into singles and dirt bikes. I understand the principles, but my hands on experience is not much. I have never jetted a carb. My bike has the stock airbox and exhaust with no mods. I plan to keep the airbox, just like it is and change the exhaust to one with a spark arrester that will probably also flow more. I don't see needing to much of a jet change. I understand that by raising the needle up it richens the fuel mixture. Is it only at idle and low speed? The main jet is for higher speed? Allen __________________ You meet the nicest people on a Honda Clone.
	0

06-30-2007, 10:21 PM	#9
red2003 Join Date: Jan 2007 Location: Northern Vermont, USA Posts: 1,271	Yes, the needle and fuel screw only control idle through mid range throttle position. If you don't plan any airbox mods, you should be fine with the stock main jet. Fatboy 250 has like 8000 miles on his Roketa with a pod filter, drilled exhaust and a totally stock carb. If you have gotten rid of the decelleration pop, and it starts and runs well, you're all set. Run it!!! __________________ First Chinabike: 2006 Roketa RSX200E Current Chinabikes: 2023 Titan DLX & 2022 Lifan KP Mini w/ 210cc BRT kit, 22 RWHP!
	0

06-29-2007, 10:16 PM	#2
tzrider Join Date: Jul 2006 Location: Texas by gawd! Posts: 407	It looks new. To "read" the plug, you have to look down at the base area of the insulator for color. Also, how far up the ground pole the tan is vs the brown, and look for specks, flecks of aluminum on the insulator if you're worried about detonation (I'm a two stroke guy, okay? ) It's somewhat of an art, but I can't tell you squat from that pic. In fact, when I'm lookin' at a plug, I like to have my magnifying glass with me and stand in good light where I can see down into the plug. If the ground pole (the part that comes out off the body of the plug) is white all the way and the insulator is white to the base, you're way lean. I like the ground pole to be dark to tan up to about half its length and the insulator to have a darkish tan color to it. That way, I'm assured I'm not too lean. Again, on two stroke race bikes, lean means death and/or severe pain. Talking seizure here and it normally happens at the end of the straight at Texas World Speedway where you're running about 175 mph full lean angle draggin' the knee diving into T1 as you chop the throttle. That way, the evil seizure monster can do maximum damage. Four strokes and mildly tuned ones at that are WAY more forgiving. Still, you don't want it running too lean for too long. You can burn valve seats and such that ain't cool to do.
	0

06-29-2007, 10:50 PM	#3
ob1 Join Date: Jul 2006 Posts: 499	Looks lean.
	0

06-29-2007, 10:52 PM	#4
Savage Join Date: Mar 2007 Posts: 732	Does the bike fire right up and idle the 1st time now? Mine has ever since I went 2 notches and adjusted the mixture. Did the muffler prior to and conical air filter after.
	0

06-30-2007, 09:20 AM	#6
tzrider Join Date: Jul 2006 Location: Texas by gawd! Posts: 407	It could be jetted fine in the idle/pilots and be way lean on top where it normally runs on the highway, the main jet. Do you know how to take a plug chop? This is the only way to read the main jetting. You run it up in a tall gear, 3rd or so maybe, as tall as there's room for where you're taking the chop. Run it at high speed, WFO high rpm, then chop the throttle, pull in the clutch, and hit the kill switch all at the same time and coast to a stop, pull plug, read. This is SOP for race bikes and pretty important on these little bikes that are run out on the highway close to their peak. This is where they live, not on the pilot jet.
	0

07-01-2007, 12:38 AM	#10
AZ200cc Join Date: Apr 2007 Location: Show Low Arizona Posts: 2,889	Ok Red I have a question, My bike starts well as long as I do not touch the throttle..But I do apply the choke. It has some popping when I let off and gear down. I am at almost 7000 ft above sea level..Do I have to jet the carb or will dropping the needle cure any of these problems? You really seem to have a good amount of knowledge.....Any help would be appreciated. __________________ <br />2001 Suzuki DR200SE<br />1997 Suzuki RM250 YIKES<br />1995 Yamaha Breeze 125 daughters<br />1991 Honda XR80r Restored<br />maybe a 2003 Yamaha TTR90
	0

07-01-2007, 08:56 AM	#11
katoranger Join Date: May 2007 Location: Altamont, Kansas Posts: 15,103	Thanks Red, I think I have it set where it needs to be right now. The little bit of popping is gone and it starts easily and idles fine. I will be keeping the stock airbox since I plan to offroad it and I don't want to risk getting water and sand in the engine. AZ200 you may need to increase you jet size due to your elevation. I am only about 1100ft. Allen __________________ You meet the nicest people on a Honda Clone.
	0

07-01-2007, 11:47 AM	#12
AZ200cc Join Date: Apr 2007 Location: Show Low Arizona Posts: 2,889	Thanks Kato __________________ <br />2001 Suzuki DR200SE<br />1997 Suzuki RM250 YIKES<br />1995 Yamaha Breeze 125 daughters<br />1991 Honda XR80r Restored<br />maybe a 2003 Yamaha TTR90
	0

07-01-2007, 12:02 PM	#13
katoranger Join Date: May 2007 Location: Altamont, Kansas Posts: 15,103	Your welcome. Red may be able to suggest a starting point. I have never changed jets. Allen __________________ You meet the nicest people on a Honda Clone.
	0

07-01-2007, 12:10 PM	#14
AZ200cc Join Date: Apr 2007 Location: Show Low Arizona Posts: 2,889	I work on cars...And thats it. I have had a lot of bikes and can fix basic stuff. But this is over my head..And I know I will screw it up without good advice __________________ <br />2001 Suzuki DR200SE<br />1997 Suzuki RM250 YIKES<br />1995 Yamaha Breeze 125 daughters<br />1991 Honda XR80r Restored<br />maybe a 2003 Yamaha TTR90
	0

07-01-2007, 04:09 PM	#15
IronFist Join Date: Apr 2007 Location: Toronto Ontario Canada Posts: 2,585	Sometimes at high revs my bike stutters, but only when I'm really slamming the throttle. When I roll the throttle it never happens. Air fuel has to stay rich or it coughs when I rev from idle speed. Idle set high to keep from stalling because it is rich at idle. Muffler is drilled, cone filter, iridium plug. I find that the iridium plug is harder to read. I did the throttle chop. Lean at rpm, rich at idle. Need to rejet, not a lot, just a little. I'd be able to back off on the air fuel screw a bit and reduce the idle as well. But I could be totally wrong. N2r.
	0