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Maintaining constant speeds between 50 and 80 mph that require very little throttle openings I get a hiccup/cutoff/stutter. I have a feeling it might be because of fueling being so lean it swings to non combustion for a split second.
Am I the only one getting this?
I do have the EJK but this only happens with the eco light on...when I think the ejk has no effect.
 

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Maintaining constant speeds between 50 and 80 mph that require very little throttle openings I get a hiccup/cutoff/stutter. I have a feeling it might be because of fueling being so lean it swings to non combustion for a split second.
Am I the only one getting this?
I do have the EJK but this only happens with the eco light on...when I think the ejk has no effect.
I do know that when I am in a parking lot doing 10-20, I get this constantly. I feel like my bike is going, "Vroom... vroom... vroom..." constantly... kind of surging.

It drives me absolutely crazy.
 

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I can feel it once in a while too. Not something I noticed in the past but now that the weather is hot and humid as hell... Sometime it depend where I get gas too. Higher octane the better... or at least try a new station.

At low speed I short shift and it fix the problem. But I don't really feel any issue cruising in top gear at 70-80 mph?

Ive been trying to get EJK to work on some O2 sensor offset for a while. Poor guy has been hammered with work. In cold weather its fine for me.
 

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I can feel it once in a while too. Not something I noticed in the past but now that the weather is hot and humid as hell... Sometime it depend where I get gas too. Higher octane the better... or at least try a new station.

At low speed I short shift and it fix the problem. But I don't really feel any issue cruising in top gear at 70-80 mph?

Ive been trying to get EJK to work on some O2 sensor offset for a while. Poor guy has been hammered with work. In cold weather its fine for me.
Yeah top gear seems fine even at lower speeds, and any speeds over about 50mph there is little to no stuttering in any gear at all really. Just super annoying cruising at a general traffic pace, and having your bike constantly surging.

The problem really amplifies itself when riding two up, even the missus commented that the bike seemed to be surging. Yamaha just says its normal to run that way, and is a quirk of a 3 cylinder engine. I told them I dont like what they refer to as their version of normal. As my version and experience of what is normal seems to differ a little from theirs, it isnt the first motorcycle I have owned...........and I hate how dealerships treat you as if it is.

But apart from that little niggle, the engine is a complete gem.

What do you refer to by sensor offset Marthy?
 

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Try to upshift one gear up. 4K rpm sometime is a B%%=. Plenty of torque down low.

The O2 sensor keep the AFR at a solid 14.7:1 doesn't matter how you tune it, the ecu take over it close loop. The EJK was able to offset that value to make it 13.8 by example. The bike will run much better. Might cost you few MPG but it will run great. I talk them into making it adjustable so ypu can still leave it oem on long ride and keep some range from the small fuel tank.
 

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Hahaha I know what you mean about 4k rpm. That is the bane of my rpm range. 4-5k rpm is where all of the surging takes place.

Good thing that immediately following that 4-5k rpm range, is 6-12k..........meaning power wheelies. No surging during power wheelies lol.
 

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I have the flash and get a slight stutter sometimes at highway cruise speeds, and I have an O2 optimizer connected to my PCV, as well as Auto Tune. The bike flamed out on me yesterday down shifting coming to a stop. First time ever. Running low octane fuel.
 

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I have the flash and get a slight stutter sometimes at highway cruise speeds, and I have an O2 optimizer connected to my PCV, as well as Auto Tune. The bike flamed out on me yesterday down shifting coming to a stop. First time ever. Running low octane fuel.
Why are you running low octane fuel? Compression ratio of this bike requires 91+
 

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The only stutter I've had was mostly cured by taking up the slack in my throttle cable. Playing in 2nd gear on Lime Creek Road (think Tail of the Dragon twisty) - I would get a stutter when engine braking into a corner totally off throttle. Basically I was playing with the throttle to be ready to power out of the corner - but the computer was picking it up as on and off throttle. The problem (for me) was in how abrupt the first touch of throttle was. A G2 throttle tamer helps a lot with making the first half of the throttle smoother - and it adds a little bit of faster rush after the halfway mark. I've also sent my ECU in for a reflash which will make it even smoother, and reduce the engine braking. What can I say - I guess I'm a 2-stroker at heart...
 

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Mine was doing the same with the Stoltec flash and EJK controller every now and again going in and out of ECO mode. Ended up disconnecting the O2 sensor for good after fiddling with it for a bit, fuel mileage is a bit worse but the bike runs so much smoother while cruising and transitioning in and out of partial throttle.
 

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Mine was doing the same with the Stoltec flash and EJK controller every now and again going in and out of ECO mode. Ended up disconnecting the O2 sensor for good after fiddling with it for a bit, fuel mileage is a bit worse but the bike runs so much smoother while cruising and transitioning in and out of partial throttle.
Is disconnecting the O2 something anyone can do, regardless of mods, or does it require certain things to be present?
 

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Is disconnecting the O2 something anyone can do, regardless of mods, or does it require certain things to be present?
If your bike is stock I would leave it alone, not going to gain anything by disconnecting it. I have not heard of any negative impacts outside of worse fuel economy when it is done on a modded bike, the electrical connector for it is behind the right hand footpeg - takes 5 seconds to unplug. Mine would still be connected if it did not interfere with partial throttle response, without it plugged in I am totally happy with the results - going through corners and having the bike transition in and out of the lean fuel map was noticeable for sure.
 

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I have the flash and get a slight stutter sometimes at highway cruise speeds, and I have an O2 optimizer connected to my PCV, as well as Auto Tune. The bike flamed out on me yesterday down shifting coming to a stop. First time ever. Running low octane fuel.
Doug I don't think it's the fuel. This has happened to quit a few people now when downshifting. The whole bike just shuts down. Almost caused me to get rear ending last time it happened to me. It's done it twice now..
 

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Doug I don't think it's the fuel. This has happened to quit a few people now when downshifting. The whole bike just shuts down. Almost caused me to get rear ending last time it happened to me. It's done it twice now..
I have the same problem and mine is completely stock and on A mode at 1500 rpms just playing with the throttle it will stall. Told the dealer and they told me I can't ride it like a 4 cylinder. I think they don't know jack....
 

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Mine was doing the same with the Stoltec flash and EJK controller every now and again going in and out of ECO mode. Ended up disconnecting the O2 sensor for good after fiddling with it for a bit, fuel mileage is a bit worse but the bike runs so much smoother while cruising and transitioning in and out of partial throttle.
^^^This.

The ECU tries to compensate to achieve a 14.7:1 A/F ratio whenever the ECO indicator is on. This is a pretty major swing from closed/open loop operations, so if it bothers you, this is the best course of action. Recommend you disconnect the battery while disconnecting the O2 to clear the memory and learned values.
 
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