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My 2014 FZ09 has developed the dreaded stuttering at just off idle while at a constant throttle. History, 2014 model bought new in 2014. Flashed by Vcyclenut in 2014 @ 5000KM. Akra pipe installed, AIS removed in 2017. Reflashed by Vcyclenut for pipe Apr 2019.

Other than the usual sensitive throttle (helped with the initial flash) I’ve had zero trouble with this bike since purchase. The initial stuttering was noticed during my last fall ride in 2018 at around 30,000km. While trying to hold a constant throttle (just off idle/closed position) I felt the bike stuttering as if it was missing, wasn’t too abrupt at the time. Absolutely no issues starting, idling, acceleration or decal. After that ride the bike was put away for the winter (battery removed). No issues during the first few rides of 2019 and then I noticed that same stuttering, again not too abrupt. During the next couple rides the stuttering became much more abrupt to the point it was dangerous. Felt like a complete engine/fuel cutout, again absolutely no issues starting, idling, acceleration or decal. Made no difference in any of the modes. No codes other the standard reflash ones which I cleared. All APS & TPS settings in diagnostic mode are well within spec. No adjustments made. Took to the internet and read a few complaints about similar issues. Replaced plugs (had already replaced at 20,000km), air filter and unplugged & checked all electrical connectors. Problem solved, bike was smooth as butter!! About 5 rides later, while I was on a bike trip down to West Virginia the stuttering begins. Again wasn’t too abrupt to start with but by the end of an all-day ride it was at its worst. Spent the next day unplugging all connectors and letting it sit for a couple hours. Problem solved, bike was smooth as butter for the rest of the trip. Took quite a while for the issue to come back this time but it did. Again no codes. This time I tried just unplugging the APS, issue disappeared for the next quick ride but came straight back on the second ride. Removed both APS & TPS to check, both within Ohm spec. That’s where I am now. Obviously something is resetting or defaulting once everything is unplugged which appears to solves the issue and then gradually in time goes out of spec but I can’t figure out what. Another interesting fact, when the airbox is off and I’m in diagnostic mode for either the APS or TPS I swear the throttle butterflies are snapping closed just before I’ve fully closed the throttle. Not sure if this is right or wrong.
 

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Did you fix your problem? I got the same thing, i'm going to clean the APS and TPS connector this weekend. Other than that I did : Airbox mod, flashed, full m4 exhaust, K&N high flow air filter, new oil filter and plugs, chain tension is good. I am lost and so close to selling this shitty bike.
 
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