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Im not rich, im lean...
- Thread starter Jawknee21
- Start date
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- Tags
- carburetors
angus67
Welder's penetrate deeper!!
have you done a plug chop?
Your mains dont cut in untill 3/4 wot. if your just riding it around, your not getting a correct reading. your only rinning on the pilot, what pilot size are you running? that seems lean by the description.
Your mains dont cut in untill 3/4 wot. if your just riding it around, your not getting a correct reading. your only rinning on the pilot, what pilot size are you running? that seems lean by the description.
cros36
thread killer
im not rich either. sucks bro.
anyways, go to the carb guide and start at page 24.
http://www.amckayltd.com/carbguide.pdf
anyways, go to the carb guide and start at page 24.
http://www.amckayltd.com/carbguide.pdf
angus67
Welder's penetrate deeper!!
http://www.iwt.com.au/mikunicarb.htm
here is a great primer to carbs. I had a awesome link to how to read plugs, cant find it. this links talks in normal talk.
here is a great primer to carbs. I had a awesome link to how to read plugs, cant find it. this links talks in normal talk.
Well, I just think you're not reading your plugs right - or in other words - you don't know how to read your plugs right. Granted, you do look at overall plug color for a reading as to whether you're too rich or lean. All white or all black means you're off one way or the other. Once you get it tuned close though, you're not going to see those kind of readings anymore. The top will be clean. Now you need to start reading the "smoke" ring, a ring of color around the porcelain inner part .....
You want this ring of color to remain at the lower 1/4 to 1/8 of the porcelain. If it creeps higher, you're too rich somewhere.
You want this ring of color to remain at the lower 1/4 to 1/8 of the porcelain. If it creeps higher, you're too rich somewhere.
angus67
Welder's penetrate deeper!!
oops sorry....1/2 to wot
Well, I just think you're not reading your plugs right - or in other words - you don't know how to read your plugs right. Granted, you do look at overall plug color for a reading as to whether you're too rich or lean. All white or all black means you're off one way or the other. Once you get it tuned close though, you're not going to see those kind of readings anymore. The top will be clean. Now you need to start reading the "smoke" ring, a ring of color around the porcelain inner part .....
You want this ring of color to remain at the lower 1/4 to 1/8 of the porcelain. If it creeps higher, you're too rich somewhere.
OH! ok. i dont know what im doing apparently. ive been expecting the whole porcelain top to be that color. 5twins, you always have a graphic or example to go with the answer to the question that has already been asked before, but somehow you have the patience to answer the question again. I appreciate your help greatly. I usually need a visual anyway since im a little slow. I have read the carb guide a couple times. maybe a couple more and ill finally be able to finish this thing. The thing is that with this EXACT same jetting i had black plugs before. and now they're all white. i dont get it. and now it kinda stumbles at around 4krpm and struggles to get to 70mph. maybe 1 up on my pilot again? i just dont want to run lean and burn something up. It was fine in the summer...
Everybody seems to have their own way of reading plugs that works (or doesn't) for them. One way that makes sense to me is read too lean from the porcelain, too rich from the ring at the end of the threaded metal, and plug heat range from the negative electrode. Too lean is tiny dark spots on the porcelain. Too rich is fluffy black on the ring at the end of the threaded part - there should be a continuous carbon ring there, but just barely. The condition there is the same as will be in the combustion chamber itself. Right heat range is when the neg. electrode changes color near its elbow. You can change where it changes color by changing heat rating.
All I can think of is that you had something off, like a stuck float or something, that was causing the black plugs and you inadvertently fixed it during one of your recent jet changes. I think you're in the ball park now as far as jetting, you just need to fine tune it. You'll need to determine at what RPM the problem is occurring. This will point you towards what jet to change. If the problem is at or just above idle, say in the 2 to 3K range, that would indicate the pilots need changing. If the problem is higher up, say at 4K and above, that would point you at the mains. You also have to determine whether the indicators you're getting are for a too rich or too lean condition. Flat spots, hesitations, or balking usually indicate a lean condition. Stumbling, gurgling, or sputtering usually indicate a rich condition. You may also want to try a test run with your pods removed. Cheap pods can cause all sorts of tuning headaches.
Yes, float height will effect the richness or leaness and these BS34s are very picky about that setting. Being as little as 1mm off can really change things. So it seems you cured your black plugs by properly setting your floats. I can't stress the importance of this enough. This is the 1st setting you must get right before you even start trying to tune the rest of the carb. You're just wasting your time if you try to start tuning and changing jets with the floats set wrong. Also, adjusting the mix screw can sometimes have no apparent effect if the floats are set wrong.
Will temperature make it richer or leaner? It was better in the summer. Now it's still lean with 142.5s and stock pilots in. Which doesn't make sense cause everyone says they use 1 up on pilots and 2 on mains with open exhaust. I have baffles.
Side note. Last night I was riding home and it was staying revved hight. Like 3krpm. Then it would eventually drop back down on its own after like 5 seconds. I couldn't make it happen and I couldn't fix it. It did it when it wanted to..
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Side note. Last night I was riding home and it was staying revved hight. Like 3krpm. Then it would eventually drop back down on its own after like 5 seconds. I couldn't make it happen and I couldn't fix it. It did it when it wanted to..
Posted via Mobile
That might be an indication that your pilots are too small. You said you have stock pilots installed which means they probably are too small. Go up one size on them to #45s. Also, I feel the 142.5 mains may be too big. Where does your break-up occur? At what RPM? Have you tried 140 and/or 137.5 mains?
At about 4k-4500? The power curve just seems to drop off. It has nothing there. Its weird, itll still accelerate but really slow. Up to 60 is fine. Beyond it struggles. I'm going to check my valves again and go up on the pilot. And down 1 on the mains. I've tried 137.5s already. I skipped 140 cause its still really lean...
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I will vouch for a big yes as well, and tell you about my experience. I had to replace a leaking or hanging needle valve and so just replaced them both and played with the float settings for amusement...
Less than 2mm +/- from the spec 22mm I went from smoking black rich exhaust that I thought was going to choke me to death, to so lean that it was hard to start and would die as soon as I twisted the throttle. So set it carefully, in good light, with good glasses...
http://www.xs650.com/forum/showthread.php?t=6344
so raising the floats makes it leaner? I got a carb rebuild kit and havent changed the float valve assembly. what does that affect? should i just put the new stuff in? I dont see a point in keeping it and not using it...
^Making the gas come closer to the top of the bowl makes it richer, and vice versa. I got the rebuild kits from Mike's which are reported pretty good, and just used the needles and seats so far. To pull the float pins I like to get some little diagonal cutters that are so sharp they will fit under the head of the pin, and then lever them out that way. People break the posts sometimes hitting the pin on the other end. When you put them back in they just have to be a little snug. The bowl blocks them from coming out. (BS34 at least).
^It's a last ditch filter to keep crap out of the carb. Stick a pick into one of the squares in the plastic and pry it off and snap it on the new seat. The o-rings that came with the rebuild kit seemed to loosen up some over time so when I had them apart once I put better o-rings on the seats from the kit.
Since your seats were hard to get out, carefully take the o-ring off and put it on the new seat. Likely a better o-ring. If the o-ring starts to leak, you might as well not have a float or needle. Put a smear of grease on the new o-ring and push the seat in till it bottoms. Don't scar any of the inside of the seat with a tool. That will cause the needle to not seal or to hang on the side.
Some people take a q-tip and a bit of 0000 steel wool and turn it inside the seat just a couple of twists to remove brass flash. I did that because my seats from the kit had flash that I could see.
Since your seats were hard to get out, carefully take the o-ring off and put it on the new seat. Likely a better o-ring. If the o-ring starts to leak, you might as well not have a float or needle. Put a smear of grease on the new o-ring and push the seat in till it bottoms. Don't scar any of the inside of the seat with a tool. That will cause the needle to not seal or to hang on the side.
Some people take a q-tip and a bit of 0000 steel wool and turn it inside the seat just a couple of twists to remove brass flash. I did that because my seats from the kit had flash that I could see.
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so i put it all together with the new parts new o ring and everything but then the float bowls wouldnt fill. the fuel wasnt going anywhere. what could it be? i checked the float height again and used the new "things" (what are the things with the spring that the floats rest on? cause thats what i used a new one of) Float valve? what could stop the fuel from going into the bowls?
