Engine Miss /Skip Help Please!

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Checked spark plugs with diaganostics, all looked like firing good. All boots to wires tight. reintalled, still the skip. maybe i need to grease the muffler bearings. LOL.
I feel your pain.. I went through all the diagnostics and checked everything I could check. In all fairness, my bike was behaving the same way to a lesser degree since I bought it new last year. After I did the first TBS, I noticed the bike sputtering more, right off idle. I tried doing the TBS with the air screws set at different openings, 1 1/2, 1, 3/4, 1/2, 1/4 turns from full close, and the best result I got, without running out of idle adjustment, was at 3/4 turns out. That and along with the Barbarian mod with the CO set at +10 seems to make the motor run the smoothest. It idles really smooth at 1100/1200 rpms but when I slowly twist the throttle I can hear/feel what seems to be a random lean missfire condition. With the motor under load I can feel it more between 3K-5K rpms. I took the bike to the dealership where I bought it and even before they listened to the engine they already told me they knew what I was describing. Supposedly, it has to do with the way the fuel injection is mapped to pass the EPA requirements and the only way to make it smoother is to add a Power Commander. I had a PC3 with the Wally smoothness map on my '06 and it really made the motor run as smooth as glass. So, now I'm saving my pennies and waiting for any good deals coming up with the holidays.

And, btw, my brother has a BMW S1000RR and it does the same thing.

 
I think that we are talking about varying degrees of misfire here. What Raven is describing is known as "lean surging" and happens with many bikes in stock form. I know that my '05 does this until I installed a PCIII. My idle is still not completely rock steady, but the surging at lower rpms with small throttle openings is completely gone.

I think probably that the OP's condition is worse and different, more acute, since he says that it didn't do it before a certain point in time. Of course it could also just be that he has become more aware of the sensation and is therefore now looking for it.

That was the thing for me. Before my FJR, I had experienced lean surging on both a '94 BMW R1100RS (fixed w/ a Techlusion EFI box) which surged pretty badly on the early Fuel Injection mapping and with a 2001 Concours (fixed with larger pilot jets), so I am all too sensitive to it.

The way that I describe the feeling is that it's like you are always bucking a gusty headwind, but only when cruising at a constant throttle. Then as soon as crack the throttle open and give it some gas it gets much smoother.

I know of people that ride bikes that surge all of the time, but because they are not sensitive to it, it just doesn't bother them. This was true even of the BMW oilhead crowd, where a good portion of owners were in denial about the rudimentary first generation FI maps. Amazingly, when BMW came out with more complex FI systems and dual spark plug heads the surging went away... ;)

edit - Forgot to mention that My V-strom also had the lean surging until I installed a PCIII on that too. Other people use a Yosh box to reprogram their ECU fuel injection maps.

The only bike I've owned recently that has never surged is my 1998 VFR800Fi. It was the first year of fuel injection for the Interceptors and is a bit different in that it is an open loop FI system. There are no Catalytic convertors, and so therefore, no oxygen sensors. Coincidence? I think not.

That is one smooth running engine. I believe they messed it up and added the cats and O2 sensor in 2000.

 
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Miss or Skip is, with engine running is sounds and feels like a plugs decides not to fire. This is randon and has no stead beat. Not to noticable at idle but it is there. seem to be worse in the 2000 to 4000 range. Can feel it missing when riding. Idles good and excellerates well, but notice this miss at steady throttle. Checked all boot to wire connections good. Held thottle at 3000 for a couple minutes with it missing, shut it down, and shot ex pipes with IR gun. All temps same + or- 10 degrees. Pulled plugs, all look good and the same. Can not identify which cylinder it is. May be random on all. Gas is kinda old, topped off with 1.5 galons of fresh and sea foam. Rode about 15 miles no help. Gonna check spark on all plugs now. Thanks for your help.
Hmmm...

"worse in the 2000 to 4000 range. Can feel it missing when riding. Idles good and excellerates well, but notice this miss at steady throttle"

If all else fails, pickup a used power commander. If it doesn't help sell it for almost what you paid for it.

skip/miss/surge/stumble/fart I know they are not the same, two of them smell funny. :blush:

 
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