Any ideas on the problem?

Dozerdriver

Registered
My bike has been acting up some at start ups. It is flooding out and sounds like it is running on 3 cylinders when it first starts ( sometimes ). Very strong gas fumes and will clear up and run fine after awhile. It seems to only do it when the bike cools down to when the cold start might come in. But hasn't done it when the bike is fully cold. I have about 6,600miles on the clock now. I have a full Tsukigi exhaust, Bazzaz Fi with custom map, and race filter. I am leaning towards the plugs and plan on pulling them in the morning for inspection. Just wondering if anyone had any other ideas or what else to check. Thanks, Dozer.
 
The two suggestions already mentioned (inspect plugs & disonnect piggyback) are both good starting points.
 
I don't buy the plug theory. I suspect that you have a dirty / stuck injector. On shut down, the fuel rail stays at pressure, and takes a while to bleed down. A leaky injector would allow that fuel down into that cylinder. On startup, the bike starts to run like a fouled plug until it eventually clears. THe plug may look fouled, but its not root cause. I would suggest first running a can of injector cleaner through first and seeing if you get an improvement. You may have to pull the plugs and send them out for cleaning and balancing. There are 2 or 3 places that specialize in clean and balance. Its something that many racers do every winter.

my .02
 
I don't buy the plug theory. I suspect that you have a dirty / stuck injector. On shut down, the fuel rail stays at pressure, and takes a while to bleed down. A leaky injector would allow that fuel down into that cylinder. On startup, the bike starts to run like a fouled plug until it eventually clears. THe plug may look fouled, but its not root cause. I would suggest first running a can of injector cleaner through first and seeing if you get an improvement. You may have to pull the plugs and send them out for cleaning and balancing. There are 2 or 3 places that specialize in clean and balance. Its something that many racers do every winter.

my .02

Very good advice, I'd still start with the easy and work my way in. Problem is, if you do change your plugs, it'll hide a problem like Draco mentioned until it fouls out again. Keep that in mind.
 
I don't buy the plug theory. I suspect that you have a dirty / stuck injector. On shut down, the fuel rail stays at pressure, and takes a while to bleed down. A leaky injector would allow that fuel down into that cylinder. On startup, the bike starts to run like a fouled plug until it eventually clears. THe plug may look fouled, but its not root cause. I would suggest first running a can of injector cleaner through first and seeing if you get an improvement. You may have to pull the plugs and send them out for cleaning and balancing. There are 2 or 3 places that specialize in clean and balance. Its something that many racers do every winter.

my .02

dirty/stuck injector sounds very likely here to me as well. I would do exactly as recommended above. Bad plugs don't really "clear", but a cylinder full of fuel leaked from a injector will.

Is there smoke coming from the exhaust while that cylinder clears? Take a close look and see if there is. Try looking in different light conditions. Black smoke = fuel (probably injector), blue-ish smoke = oil (probably valve seals, seems unlikely), white smoke (accompanied by a sweet smell)... you don't want to know, so let's just assume it's the injector.
 
I don't buy the plug theory. I suspect that you have a dirty / stuck injector. On shut down, the fuel rail stays at pressure, and takes a while to bleed down. A leaky injector would allow that fuel down into that cylinder. On startup, the bike starts to run like a fouled plug until it eventually clears. THe plug may look fouled, but its not root cause. I would suggest first running a can of injector cleaner through first and seeing if you get an improvement. You may have to pull the plugs and send them out for cleaning and balancing. There are 2 or 3 places that specialize in clean and balance. Its something that many racers do every winter.

my .02

I agree with your theory,but if the injector was leaking down into the cylinder would'nt the fuel also eventually leak past the piston rings and show up in the oil pan?(if the bike was sitting for a while) Ive seen this happen on cars .
 
I agree with your theory,but if the injector was leaking down into the cylinder would'nt the fuel also eventually leak past the piston rings and show up in the oil pan?(if the bike was sitting for a while) Ive seen this happen on cars .

I believe it typically does unless you are lucky enough for it only to pool in the valve recesses on the piston I guess. It doesn't have to sit very long for that to happen though. It depends on how much fuel actually slips by as to how bad it can get, but that is another great reason to take care of this problem asap.
 
dirty/stuck injector sounds very likely here to me as well. I would do exactly as recommended above. Bad plugs don't really "clear", but a cylinder full of fuel leaked from a injector will.

Is there smoke coming from the exhaust while that cylinder clears? Take a close look and see if there is. Try looking in different light conditions. Black smoke = fuel (probably injector), blue-ish smoke = oil (probably valve seals, seems unlikely), white smoke (accompanied by a sweet smell)... you don't want to know, so let's just assume it's the injector.

It is black smoke.. very strong fuel smell. Clears up and runs fine. Only does it when I have been sitting for a bit but not all the time. Did notice the idle doesn't seem as smooth as it used to be. I will try some injector cleaning and inspect the plugs. Thanks much.
 
It is black smoke.. very strong fuel smell. Clears up and runs fine. Only does it when I have been sitting for a bit but not all the time. Did notice the idle doesn't seem as smooth as it used to be. I will try some injector cleaning and inspect the plugs. Thanks much.

Dirty injector can cause that bad idle as well. Let us know how it goes.
 
Assuming this is a fuel problem, I would disconnect the bazzaz first before I would start digging into the injectors and spending money dumping fuel injector cleaner in the gas. If you are using good gas it has lots of detergents. If you've removed the injectors before then it is possible that some junk has made its way in there but if not then I would look some other place first.
 
Last edited:
Ok..here is some pics of the plugs. They look all the same color with no signs of trouble. I put some STP fuel injector cleaner in and will keep you all updated if it clears up. Thanks.

0710091637b.jpg


0710091637a.jpg


0710091638.jpg
 
Assuming this is a fuel problem, I would disconnect the bazzaz first before I would start digging into the injectors and spending money dumping fuel injector cleaner in the gas. If you are using good gas it has lots of detergents. If you've removed the injectors before then it is possible that some junk has made its way in there but if not then I would look some other place first.

Also a good point.
 
If the other recommendations don't find anything, I would check all the pins on your Bazzaz connectors with the fuel injectors. If the map is fine, that seems to be the only other problem people have with the Bazzaz (getting a good connection with the injectors)....
 
Well, tried the injector cleaner and thought the problem had gone until last night when it did it again. Not sure what the problem is but it is driving me nuts. Might put the bike back to stock to see if it stops. I don't want to run the pipe without the bazzaz for I think it will run lean. Any other ideas what to look for or check before I switch back would be appreciated. Thanks, Dozer.
 
If I recall, you have a Gen II? If the O2 sensor is still available for use it will run fine. It still sounds more like a dirty injector. If it does it with the Bazzaz off of it, it's most likely the injectors. I have run Lucal injector cleaner through a few vehicles with good success. I also only run 91 octane in my vehicles. It may be overkill on my truck and FJR, although my truck does get better mileage on it, but they both run very clean.
 
Heat rings look good...can you check EGT's at the header tubes with an infra-red thermal unit. Let the bike idle at 1500 RPMS check and at 2000 RPMS then check see how the temps vary between cylinder..caught a dead coil and injector using this method.
 
Back
Top