Bike behaving oddly? Wierd idle, running rich ETC

RubyRider

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Hello all!

Perhaps I'm being paranoid, but I noticed something off about my bike that may or may not have already been there. A friend of mine is moving out of state so he stopped by to say goodbye. He hadn'
t seen the new bike so I started it up for him. I revved it a few seconds after starting and it bogged down when I released the throttle and actually died. Started again and did the same thing just a little less aggresive and it started "Idling"? It was go up rpm then back then up and back down etc. The exhaust fumes were a little thicker than usual (I think) as well. He mentioned it might be running a little rich. I did replace the stock muffler with Radiant Cycles Shorty, However I was under the impression that it doesn't really later anything on the bike.

Am I being crazy? This is my first bike so I would love to get educated.

Thanks.
 

TacomaJD

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Definitely nothing to do with the exhaust change. Bad fuel perhaps? I would probably keep riding it unless it's too bad to ride safely, to see if it gets any better/worse, put some more fuel in it, etc.
 

TacomaJD

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Wait a minute...you say you revved it shortly after starting it. My 2013 NC sounds different each time it is cranked, for a few seconds, then goes to normal sound and idle. Can't remember if my 2016 model does it or not. It's like the ECU is programmed to start up in a rich cycle to warm it up or something, then after a few seconds, it leans back out to normal.

Also, if I start the bike and give any throttle input, it revs and idles higher for a minute then comes back down. Supposed to start them without any throttle input, especially if the bike is cold, until after 5-10 seconds have passed (even then it's not good to rev a cold engine very high).

If you walk out to the bike, start it, and do not touch the throttle and just leave it be.....does it still do it? If so, video it. I'm betting there's nothing wrong with it at all.
 

Doc True

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Does the fan come on when you start the bike? Some of these symptoms sound like those I had when the wire to the coolant temp sensor was cut
 

RubyRider

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Wait a minute...you say you revved it shortly after starting it. My 2013 NC sounds different each time it is cranked, for a few seconds, then goes to normal sound and idle. Can't remember if my 2016 model does it or not. It's like the ECU is programmed to start up in a rich cycle to warm it up or something, then after a few seconds, it leans back out to normal.

Also, if I start the bike and give any throttle input, it revs and idles higher for a minute then comes back down. Supposed to start them without any throttle input, especially if the bike is cold, until after 5-10 seconds have passed (even then it's not good to rev a cold engine very high).

If you walk out to the bike, start it, and do not touch the throttle and just leave it be.....does it still do it? If so, video it. I'm betting there's nothing wrong with it at all.
That's probably what is going on, as when I normally ride, I start it to let it warm up, let it sit and put on my helmet and gear. I tend to be paranoid when it comes to vehicles as I had a string bad luck when I was high school with vehicles.
 

Bcsmith

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Soooo RubyRider. When I got my NC I was instructed to never crack the throttle on a cold engine. Always warm the bike up completely first. If this is only a cold engine issue just steer clear of revving a cold engine.
 

670cc

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On a four stroke, fuel injected motorcycle, I can see no reason to ever rev the engine in neutral or with the clutch pulled in. What would be the point, except to make noise?
 

RubyRider

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Wait a minute...you say you revved it shortly after starting it. My 2013 NC sounds different each time it is cranked, for a few seconds, then goes to normal sound and idle. Can't remember if my 2016 model does it or not. It's like the ECU is programmed to start up in a rich cycle to warm it up or something, then after a few seconds, it leans back out to normal.

Also, if I start the bike and give any throttle input, it revs and idles higher for a minute then comes back down. Supposed to start them without any throttle input, especially if the bike is cold, until after 5-10 seconds have passed (even then it's not good to rev a cold engine very high).

If you walk out to the bike, start it, and do not touch the throttle and just leave it be.....does it still do it? If so, video it. I'm betting there's nothing wrong with it at all.
Coincidentally, my NC is also a 2013
 

TacomaJD

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I have a 2013 and it has a Yoshi exhaust on it, so I can hear the difference in tone easier on it when it starts up, but I rode my 2016 to work today (stock exhaust) and paid attention to it when I started it, same thing....deeper idle when started, then changes to quieter smoother idle after a few seconds. It's just something programmed into the computers on these bikes.
 

RubyRider

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I have a 2013 and it has a Yoshi exhaust on it, so I can hear the difference in tone easier on it when it starts up, but I rode my 2016 to work today (stock exhaust) and paid attention to it when I started it, same thing....deeper idle when started, then changes to quieter smoother idle after a few seconds. It's just something programmed into the computers on these bikes.
SO what your saying is.. I'm just crazy? lol. Thanks for the info.
 

Griff

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I think with any fuel injected motorcycle it is best not to interfere with its startup cycle and that echoes what is being said above. I start mine and let it run at its own pace for a minute or so until the tickover drops a little and then ride off. However I never give any engine a hard time when cold and will travel several miles before piling on the throttle.
 

DirtFlier

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I've once had that happen on my other bike (NT700V) when I had a brain fart as regards cold startup with Fi.

By the way, there is no reason to rev the engine while the bike is stationary. I taught MSF courses for 16-years and some male students felt a need to do that so I'd ask then "why are you doing that?" They never had an answer and probably felt that revving while stopped was a requirement for riding a motorcycle!
 

RubyRider

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I think with any fuel injected motorcycle it is best not to interfere with its startup cycle and that echoes what is being said above. I start mine and let it run at its own pace for a minute or so until the tickover drops a little and then ride off. However I never give any engine a hard time when cold and will travel several miles before piling on the throttle.
This is the first time I've had any experience with a running bike. My previous bike was a 2004 vulcan 750 that I was wokring on getting back on the road. It was carbed.
 

Olythom

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Quote -“By the way, there is no reason to rev the engine while the bike is stationary.”

My NC was a DCT and I had to learn very quickly that you don’t rev the engine at a red light, else the bike would jump out from under me... ;-)
 
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