Clunking on shifting and acceleration

spongehead64

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Does anyone else notice a clunky sound upon accelerating after shifting gears on a 2013 NC700X? I have checked the chain slack and it is within specifications. Could it be too much free play in the throttle cable so I’m actually letting it back off too far when shifting? Any advice would be greatly appreciated!
 

670cc

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Is the bike new to you or have you had it a long time? Did the symptoms you describe start happening suddenly?
 

670cc

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Again, did the symptoms you describe start happening suddenly?

Additional question: what is the engine RPM when you experience this “clunky sound”?
 

670cc

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Again, my question in post #4 was, what is the engine RPM when you experience this “clunky sound”?

I suspect you are experiencing normal behavior for this engine if it is under load at a low RPM, but you have given too few details for someone remotely to say if their bike behaves like yours. I’m even assuming your bike has a manual, not automatic transmission, as you have not said either way. With the limited information given so far, if the clunky sound bothers you I would simply suggest keeping your engine speed higher by shifting later during acceleration.
 

670cc

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It is a manual transmission. You may very well be right. Maybe I’m just shifting too soon!
Perhaps that’s it. The NC700 engine does not run smoothly under load below 2000 RPM. In the upper gears especially, the engine will thump and clunk, for lack of a better description, if it is loaded heavily below maybe 2500 RPM. This is not going to damage it, but if you want it to run smoother, keep the RPM a little higher when accelerating by delaying your upshift.
 

spongehead64

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I will check the chain slack again also. I looked at it a few weeks ago and it was fine. Maybe setting it to the tight side of the accepted range would help a little also.
 

670cc

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I will check the chain slack again also. I looked at it a few weeks ago and it was fine. Maybe setting it to the tight side of the accepted range would help a little also.
Loose side of spec is better for longer chain life. I would not set it to the tight side. The chain will wear more and make whining, singing noises.
 

spongehead64

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I will check it again and if it close to the high side then, I will leave it. You sound like you know this from experience so that’s good enough for me. I will just wind it up more before shifting and see if that helps!
 

TacomaJD

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I will check the chain slack again also. I looked at it a few weeks ago and it was fine. Maybe setting it to the tight side of the accepted range would help a little also.


As 670cc said, do not run a chain on the tight side, ever. Adjust the chain to where there is around 1.5" of play in it when pushing upward in the middle of the chain on the bottom side.

Wind that baby out, it's a motorcycle, not a go cart! You aren't going to hurt that engine revving it a little more....actually probably better for it than lugging it around. wind up to about 3500-4k rpms and shift through the first few gears, then you can shift a little earlier going into 5th and 6th provided you are carrying enough speed. See if that doesn't get rid of the clunking you are experiencing.
 

davidc83

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Check the chain for kinks....inside the front sprocket cover, there is a tab which sticks out from the cover, over the chain...kinks in the chain can make contact with the tab and cause a clunking sound when shifting and accelerating...if kinks in the chain, time to replace the chain...
 

Sandspike

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Check the chain for kinks....inside the front sprocket cover, there is a tab which sticks out from the cover, over the chain...kinks in the chain can make contact with the tab and cause a clunking sound when shifting and accelerating...if kinks in the chain, time to replace the chain...
I had that problem and it was caused b a single very stiff chain link. I found it by completely loosening the chain and checking every link till i found the very tight one. That kink will stand up and wack the metal bar that is just above the chain on the inside of the front sprocket cover. I think that curved bar is a safety device to insure that the chain cannot climb off the front sprocket so it is very close to the chain. Funny that the clunking only happened when maintaining speed or accelerating and on decelerating it would disappear.
 

Speedfilm

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It may be the nature of the engine vs ones with higher redline and torque curves. Old habits hard to break for me, I'm used to a crotch rocket powerband where my shifts occured just below there the power really comes on so no instant burst of torque when I nail the throttle. On the NC with its much lower powerband, I end up shifting right in the meat of the torque curve and it will surge forward as I release the clutch if I have the revs up to high.
 

Jphenry

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The shifting guidance in the owners manual for mph is quite low. Wring it out a little. The engine will thank you and you should have more fun...
 

Janus

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Or, shift when it says to and enjoy 70+ mpg

I have 71mpg over about 49500 miles

There's a certain thrill to be getting close to 80mpg on a full size bike. If you've never giggled on the freeway going 55 in a 60, you've never lived
 
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