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Discussion Starter #1
My 2006 has been through a lot of strange problems, 99% of which are all fixed and it's (mostly) running like a top now. However, I have this wierd stutter at right around 4200 rpm. It feels almost as if it's getting gas, then it's not, then it is, then it's not, etc. This is pretty quick, like it's "spitting" gas at the engine, if you will. I'm not all that savvy with the inner workings of engines, EFI, etc, so I apologize if my description is crude.

Of course, I can just drive "around" this rpm, but I'd like the get the problem fixed.

I realize this topic has been covered in the forums, but my searches found results that were similar, but not the same. So, if you don't mind me picking all your collective brains, I could use some direction.

My bike was recently serviced - it's always done this, but it seems a tad more pronounced now, possibly because my engine is running properly for the first time since I owned it. The tech (who I trust) assured me it's mapped correctly for my TOR pipes. Like I said, it runs great except for this "hole" at around 4200rpm.

Any suggestions? Good places to start? Thanks in advance for any advice you can offer.
 

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Sounds similar to a problem I had. On my bike, the rough running went from 4000 to 5000 rpm. Edinburgh Triumph checked the bike over and assured me the correct tune had been installed (I have TORS also). Gradually, however, it became less rough and now seems to be running fine. Dunno why.
 

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the two of you probably have the same problem. It is probably the mapping, yes you may have the proper tune loaded but nothing compares to fine tuning. Tune boy and some time are the answer. Oh, and the fact that it is more pronounced after the service, your mechanic probably reset all of the adaptions on your bike (this is normal) and it takes some heat cycles to let the bike adapt to the environment. Also these bikes do not automatically adjust for ethanol and non ethenol fuel so if you go back and forth with these your bike will act different each time. Pick one type of fuel get your ECU set up for that fuel and stick with it.
 

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Discussion Starter #4
Excellent advice, thanks. I always use the same exact fuel, so that's no concern. I've thought about making the plunge into a TuneBoy, I think it's maybe that time.
 

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Excellent advice, thanks. I always use the same exact fuel, so that's no concern. I've thought about making the plunge into a TuneBoy, I think it's maybe that time.
Also find a reputable dyno shop with an O2 sensor and see what a couple pulls cost. A dip that pronounced should be indicated very clearly in the A/F ratio. If you you can feel it its possible that there is an issue across that the board, and you really should do a before and after dyno with the tuneboy anyway. Anytime you are messing with tuning, well, the proof is in the pudding and the dyno is the proof.
 

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I had mine dynoed after the TORS was fitted and the curve was very healthy (122 rwbhp).
I should have mentioned my rough patch occurred when holding a tiny throttle opening between the afore mentioned rev range.
 

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I had mine dynoed after the TORS was fitted and the curve was very healthy (122 rwbhp).
I should have mentioned my rough patch occurred when holding a tiny throttle opening between the afore mentioned rev range.
Hmmm, have you had the thottle boddies sync'd lately. Mine get out of whack and I end up doing it about once year. I got a carbtune for $75 on E-bay and it'll make the task a lot easier. Sounds like the EFI is "searching", and thottle boddies are usually a big offender for that.
 

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Discussion Starter #8
Interesting. I should have mentioned that mine doesn't do this so much at a healthy punch on the throttle, it's when attempting to kinda cruise along at an even throttle, right around 4200rpm.
 

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Tripped1 has a good point, I was just assuming that everything was in proper tune from the shop and there was still an on going issue thats all. The T-bodies should be syncd at the regular tune up intervals at the shop.
 

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Tripped1 has a good point, I was just assuming that everything was in proper tune from the shop and there was still an on going issue thats all. The T-bodies should be syncd at the regular tune up intervals at the shop.
Only thing that buggs me about that is that it is at 4200. There is usually a bit of a dip in the 4000-5000 range powerwise, but it normally just a flat feeling. However, half-way up the tach isn't not usually where TB syncing presents itself. I'm wondering if

Searching as it relates to the TBs is usually a low RPM thing that you notices less once the motor gets spinning.

Bvivers, is there an O2 reading on your dyno sheet? It sounds like a lean spot the more I think about it. Scarey part there being that motor make more power when they are lean due to increased combustion temps. The other thing I would do is pulls the plugs and see wht they look like. They should be a sort of gray, not black and wet, and definately not white.

The other possibility is a stuck SAI or exhaust valve if you still have one. Bascially there is something affectiong the flow of air or fuel.
 

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Unfortuneately, no. I'll ask the geezer that dynoed it if he has that info. The thing is, as time went on, the rough patch gradually got smoother. It's not totally gone, but it's a lot better. The roads here in Scotland are covered in salt and grit (cold snap just now) so I haven't taken the bike out for quite a while. I'll report on how it's running when the weather is a bit better.
 

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That lean-light-throttle-cruising-RPM stutter is there, and is taken care of in some Tuneboy tunes. The only downside is the richer tunes suck more gas. I notice the difference in mpg when riding at cruise, but they are essentially the same when riding in the "fun" mode. I usually keep mine with a more economical tune for longer trips if I need the range, and the richer tune for all other times.
 
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