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Smoke from exhaust

11555 Views 55 Replies 14 Participants Last post by  thecomputerguy
As of yesterday I put on 250 easy miles and throughout the day my cousin behind me said when I get on the throttle it blows smoke from the exhaust pipe. Smells like un burnt fuel so I'm guessing I'm running rich but why all of a sudden now? 2400miles on the bike. I also noticed its been back firing more and more. I have a cobra slip on exhaust but have had that on since new. Any ideas anyone???
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I would be checking everything that could cause the bike to be running rich i.e. air filter, spark plugs, valves. Just start with the easier and free things first and work your way up the list. Also ask yourself if there is anything that you have changed on the bike when the problem started.

+1 on that.
Dirty, plugged air cleaner could cause the problem. How many miles since it was changed, same with the plugs and oil and filter. Also a dirty O2 sensor can cause issues. Good place to start.
Hmm, hard to tell in the vid but looked more like either blue or greyish white. have you checked the level of the anitfreeze? Hard to diagnose from a vid but water vapor or antifreeze would burn white. Oil would have a blueish tint. definitely more smoke than normal. Any smell to it e.g. anti freeze would have a sweetish smell.
Thank you Toby. couldn't have put it better!

That's the million dollar question and that's where the answer lies, and that's why nobody can get it right by trial and error and smelling the exaust and test running it unplugging this or that, because the variables are constantly changing. There are many sensors involved in the fuel processing information procedure in the entire EFI system. The 02 sends the final emissions readings, but you have the throttle position senor, load sensor, ambient air temp sensor, barometric pressure sensor, internal engine temp sensor, altitude sensor , ignition timing sensor, gear sensor, RPM sensor, coolant temp sensor etc. etc. Probably missed some but all these work hand and hand in sending ever changing info to the ECM(Engine Control Module) also know as the ECU, the brain that reads ALL this info and makes multiple changes every second to air fuel mixture.
The only guys that have ever got it perfectly tuned and never had a single problem with ANY aftermarket fuel possessor are the ones that have had their system professionally tested and individually mapped specific to their bike.
No disrespect intended, but I can't understand why anyone would think that they could do the work that was professionally engineered and designed to be done by a computer. I guess they just don't understand what all is involved here and I don't know why the companies selling these products don't tell them.
I did extensive research on the subject and came to the decision I wont do a stage 1 power up grade until I can afford all three mods, pipes, intake and fuel possessor plus have it professionally mapped.
I guess I should have posted this on one or all of the fuel possessor threads.
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