Burning Rich but runs good

FixMeUp

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I have a 03 busa with a 99 motor on it I believe I got it toward the end of summer and didn’t get to ride it a whole lot and honestly couldn’t afford too. The guy I got it from had it apart and had plans of putting a turbo on the bike but never got to it. My bike is getting 11 miles to the gallon. Yes that’s what it reads and that’s me calculating myself. I have checked the plugs, changed the air filter, and checked all the vacuum lines they are all good. I always run 93 in all of my bikes some guys have told me to run 87 in this one. I am at a loss here though I am a diesel mechanic by trade and am very mechanically inclined so I can do most anything I need to do I’m just at a loss on what else to try here. At idle cold or at operating temperature going to high revs in neutral, riding it in gear or pulling the clutch in it shoots black smoke and back fires and a flame on the right hand side of the dual exhaust. It isn’t tuned doesn’t have any performance mods. The pair valve has been removed I didn’t know what the heck it was until yesterday and I come to find out that it didn't have block off plates so I have those ordered but no one seems to think this is my real problem. I have no idea. Looking for any and every opinion and ideas to help me out LOL.

A little bit of what I know about the bike.
-title reads a 03 pulled the fairings off yellow paint on the side of the case reads 1999
- motor has 02-07 style fuel rail and pump, no return line feed line runs into the right side of the fuel rail.
-Dash reads 11k miles.
-It has stock headers with Wiley co exhaust on it.
-will start and run and ride.
-Runs way better than I expected to be so rich I had a gsxxr 750 the busa is another monster.
-plugs gapped to .030 and coil
 
Welcome to the oRg.
Go to the New Members section and introduce yourself, and post some pics of your bike for us please.
Re the rich running issue . . .
Assuming the air filter is not badly blocked (at the low mileage I doubt that) the first thing to check is the MAP sensor (IAP sensor Suzuki call it, Intake Air Pressure sensor), if this is damaged, faulty or disconnected from the vacuum hose that is attached to it, it can cause a very rich running condition.
Also check the fuel pressure, should be around 42 psi, and the injectors for leakage or bad spray pattern
Others will chime in shortly with anything I've missed.
 
I w
Welcome to the oRg.
Go to the New Members section and introduce yourself, and post some pics of your bike for us please.
Re the rich running issue . . .
Assuming the air filter is not badly blocked (at the low mileage I doubt that) the first thing to check is the MAP sensor (IAP sensor Suzuki call it, Intake Air Pressure sensor), if this is damaged, faulty or disconnected from the vacuum hose that is attached to it, it can cause a very rich running condition.
Also check the fuel pressure, should be around 42 psi, and the injectors for leakage or bad spray pattern
Others will chime in shortly with anything I've missed.


I will do that I have checked all vacuum lines the IAP sensor appears to be in fine condition the only code it throws is a tps code but I adjusted that and it went away the air filter is spotless a K&N there is no visible leakage around the injectors what’s the best way to go about checking the spray patter? The bike is kind of hard to start every now and then but will sit and idle all day and runs pretty decent but I’m sure could and will eventually run so much better.
 
I w



I will do that I have checked all vacuum lines the IAP sensor appears to be in fine condition the only code it throws is a tps code but I adjusted that and it went away the air filter is spotless a K&N there is no visible leakage around the injectors what’s the best way to go about checking the spray patter? The bike is kind of hard to start every now and then but will sit and idle all day and runs pretty decent but I’m sure could and will eventually run so much better.
You'll need to actually remove the injectors from the cyl head and the best way is to send them to an injector specialist to be checked thoroughly.
To check them your self you can hook up fuel pressure to them and see if they leak or dribble.
Hold each one a few inches away from a white sheet of paper and open the injector with power supplied to it for a second or two.
You will soon know from the spray whether it looks ok or not . . being a diesel mechanic you will be familiar with injectors I'm guessing.
Have you checked fuel pressure yet?
Have you checked the spark plug condition and color yet?
 
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the You'll need to actually remove the injectors from the cyl head and the best way is to send them to an injector specialist to be checked thoroughly.
To check them your self you can hook up fuel pressure to them and see if they leak or dribble.
Hold each one a few inches away from a white sheet of paper and open the injector with power supplied to it for a second or two.
You will soon know from the spray whether it looks ok or not . . being a diesel mechanic you will be familiar with injectors I'm guessing.
Have you checked fuel pressure yet?
Have you checked the spark plug condition and color yet?
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I haven’t yet checked the fuel pressure I will get around to that tomorrow the plugs are pretty well black I cleaned them up the best I could and made sure they were gapped correctly I am from a little bitty town in the mountains and don’t have anywhere open to get plugs until Monday unless I can get them from advance I’ll just have to call and see. Yes I am familiar with Injectors I was going to upload a couple of videos but the site won’t allow me to do so.
 
the You'll need to actually remove the injectors from the cyl head and the best way is to send them to an injector specialist to be checked thoroughly.
To check them your self you can hook up fuel pressure to them and see if they leak or dribble.
Hold each one a few inches away from a white sheet of paper and open the injector with power supplied to it for a second or two.
You will soon know from the spray whether it looks ok or not . . being a diesel mechanic you will be familiar with injectors I'm guessing.
Have you checked fuel pressure yet?
Have you checked the spark plug condition and color yet?
I haven’t yet checked the fuel pressure I will get around to that tomorrow the plugs are pretty well black I cleaned them up the best I could and made sure they were gapped correctly I am from a little bitty town in the mountains and don’t have anywhere open to get plugs until Monday unless I can get them from advance I’ll just have to call and see. Yes I am familiar with Injectors I was going to upload a couple of videos but the site won’t allow me to do so.
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Welcome....I agree with Kiwi, it sounds like an injector problem to me...
 
I will see what I can figure out on it today I have ran a couple of tanks of sea foam through it hoping to clean it up but it hasn’t helped much if at all.
 
Being as you just swapped the engine, you may have crossed the intake air temp sensor, and coolant temp sensor. The plugs are exactly the same, and hang in the same location so it’s easy to get them crossed. This will cause an excessive rich condition.

One plug is green, the other is black. Off the top of my hand, I can’t remember what plug goes to which, but the intake air temp plug runs right in to the injector harness, or real close to it. The IAT goes in the the main harness that runs along the frame, a little more forward of the other plug that loos the same.
 
It isn’t tuned doesn’t have any performance mods. The pair valve has been removed I didn’t know what the heck it was until yesterday and I come to find out that it didn't have block off plates so I have those ordered but no one seems to think this is my real problem.
I have heard removing the pair allows a buildup of carbon on the exhaust valves which might explain the black smoke. I have the PAIR removed on both my bikes and no problems. There was quite a clog of carbon under the block off plates when I took the block off plates off my ZX-14.

As far as the running rich...IDK. That might be a separate problem from the smoke maybe?
 
Being as you just swapped the engine, you may have crossed the intake air temp sensor, and coolant temp sensor. The plugs are exactly the same, and hang in the same location so it’s easy to get them crossed. This will cause an excessive rich condition.

One plug is green, the other is black. Off the top of my hand, I can’t remember what plug goes to which, but the intake air temp plug runs right in to the injector harness, or real close to it. The IAT goes in the the main harness that runs along the frame, a little more forward of the other plug that loos the same.

I didn’t swap them but the guy that had it before me must have I’ll definitely look at it and see!
 
I have heard removing the pair allows a buildup of carbon on the exhaust valves which might explain the black smoke. I have the PAIR removed on both my bikes and no problems. There was quite a clog of carbon under the block off plates when I took the block off plates off my ZX-14.

As far as the running rich...IDK. That might be a separate problem from the smoke maybe?

Possibly I’m going to install my block off plates and see if anything changes
 
Possibly I’m going to install my block off plates and see if anything changes
It would seem having the reed valves open would allow clean air to flow in with the exhaust continually and without the regulation of the solenoid. That could be why you are getting some exhaust popping when you don't expect it.
 
being as how the prolonged effect of the angle of the dangle not being totally equivalent to he heat of the meat one would ponder as to the relevance of the party of the first part not being properly equipped with a pie nor the means in which to facilitate the production of said pie regardless of the fact that a pie and only a pie could fix the problem. that said, use some Zaino on it.
 
Do any of you guys that work on these bikes a lot think it’s possible that maybe the timing is off? I have a few videos of the bike running I wish it would let me post them but I can’t for some reason... I had to get my local parts store to order plugs for me I’ll pick them up tomorrow but still don’t think this is my issue being that it runs good and idles good. And I would be willing to have it dyno tested and try to figure it out that way but it is at least a hour and a half one way trip to a shop that works on these bikes and over 2 hours one way to anyone who has a dyno. So I’m trying to do what I can on my own with your all’s help if anyone wants to see the videos or think they could help me better by seeing the videos send me a message on here and I will figure out how to get the videos too you. Thanks for all the input so far it’s a little frustrating but it gives me something to tinker on and I enjoy working on it... just don’t have the money to spend a fortune at a shop or traveling to dyno it especially since my first child will be here in July... I lucked up though she’s letting me keep the bike mainly because we had a miscarriage back last spring and she loved riding my 750 with me and going different places on it to ease our minds and get the thoughts of losing our child off of our minds.. but on a happier note there’s gonna be another Busa fanatic coming in to the world in July!
 
To post videos here, you must first upload them to YouTube or similar 3rd party video host. Then, copy and paste the address bar as a link here on this thread as a post.
You need to have a YouTube account to upload your videos.
Hope this helps, any questions just ask.
 
It's definitely burning fuel in the exhaust, weird that it's only smoking on one side....
Timing may be off, @Kiwi Rider should be able to tell you how to check....
 
It's definitely burning fuel in the exhaust, weird that it's only smoking on one side....
Timing may be off,

I noticed that too and the side it’s smoking more out of the exhaust is a lot warmer a lot quicker, it sits and idles perfect will sit and idle until it’s out of fuel and you can ride it all day and never have an issue and never smokes until you down shift and take off the. It puffs one quick puff and clears up I’m not riding it right now because I am afraid to ride it like this and ruin more stuff
 
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