Bike feels off

[Chestnut]

Last Tuesday I went for a longish ride and the bike was feeling a little off. Like the chain needed lube or something. Lubed when I got home, took her out later, still felt a little off. Later in the week I was rolling along in 2nd gear in traffic, and she kicked into neutral. Didn't think my hand was on the clutch, but was focusing on the cars around me, didn't do it again, so I went on my merry way. She's been shifting a little rough, but was due for an oil change. This past Saturday I did the 24k service, a couple valves were tight, but nothing else going on.
Now, from about 20-25mph, only in 2nd gear, I'm feeling a sort of pulsing. It's very noticeable. And unpleasant. Anybody got ideas as to what might be causing this?

 

[silverhound]

I would check the tires first for any abnormalities. Then get it up on the center stand or a lift and make sure both wheels are spinning freely. Could be bearings, could be brakes rubbing. That's where I would start anyhow. Hopefully not any kinda of a tranny issue. Anyhow see if those tests reveal anything.

 

[searsboy]

I'd check the chain for tight spots and make sure it's aligned properly.
Good luck.

 

[Old Can Ride]

Sounds like one of those things at will take time to figure out. Keep looking and checking everything.

 

[max cooper]

I would also check the tires for cupping . And of course tire pressure. I was feeling something out of the norm a while back too. The bike just didn't feel planted and tended to wander a bit on some surfaces. So I checked my tires. My front tire was cupping quite a bit. Shortly after, I picked up a nail in that tire. I ended up installing a new tire, same brand and model. The strange feeling the bike had disappeared. It feels 100% now. Just thought I'd toss that into the pot. Good luck.

 

[L.B.S.]

Odd that it seems to be only 2nd gear in which this is occurring, though. One would think that ruled out "the usual suspects" kinda thing, as far as kinked chain links, tires, and so on.

I keep having to remember with modern day bikes and EFI/ECU, throttle position sensors etc., etc., sometimes wierd stuff can be not mechanical per se; but also stray into the electrical spectrum for potential culprits. Like if there was some strange reason for the ECU to muck with the timing or fuel mapping at closed or partially opened throttle in 2nd gear for example. (not implying this, just speculating, sorry, chestnut )

Lord knows what it was that caused all my early angst with the infamous 6th gear thrumming thing at a precise rpm, that suddenly vanished one day.


Does it happen regardless of rpm or speed, but only 2nd gear? At a steady throttle input? Does it "feel" like it's a vibration from the engine or chassis? What happens if you pull in the clutch, or manipulate the throttle a fair amount? Does the pulse fade as the rpms go up or down?

 

[Chestnut]

It's only in second gear that I get the distinct pulsing. 20-25mph being the worst. Same speed in first or third, no pulsing. It feels like it's coming from somewhere in the engine, directly under me.
Had a good listen and found that the rear brake rotor is tweaked. Rubbing at certain points when I spin the wheel. So new rotor and accoutrements ordered this morning ($300+, ouch). Doesn't make sense that it would cause the problem this way, but will find out next week when the parts come in.

 

[SergeantChuck]

What about Fuel pressure regualtor? Anyone? I don't know this bike well enough but do we have one and can't that cause pulsing? Why it is only happening in 2nd is odd and should rule out the brake issue.

 

[SergeantChuck]

Odd that it seems to be only 2nd gear in which this is occurring, though. One would think that ruled out "the usual suspects" kinda thing, as far as kinked chain links, tires, and so on.

I keep having to remember with modern day bikes and EFI/ECU, throttle position sensors etc., etc., sometimes wierd stuff can be not mechanical per se; but also stray into the electrical spectrum for potential culprits. Like if there was some strange reason for the ECU to muck with the timing or fuel mapping at closed or partially opened throttle in 2nd gear for example. (not implying this, just speculating, sorry, chestnut )

Lord knows what it was that caused all my early angst with the infamous 6th gear thrumming thing at a precise rpm, that suddenly vanished one day.


Does it happen regardless of rpm or speed, but only 2nd gear? At a steady throttle input? Does it "feel" like it's a vibration from the engine or chassis? What happens if you pull in the clutch, or manipulate the throttle a fair amount? Does the pulse fade as the rpms go up or down?

I'm not a motorcycle mechanic and to be honest I always buy and extra maintenace package and let the dealer do most of it. I do the farkles myself. I do work on heavy equipment which although different is still similair. I like some of the things you have suggest although I always have a tendancy to jump the gun. The fact that it is only happening in 2nd at a specific RPM should rule out anything associated with brakes, chain, tires, sprokets, and roatational type items. I ahve seen similair things on heavy equipment and ECU (We call ECM) software was the culprit. I wouldn't be surprised if it was somehting along the lines of what you ahve stated.

I guess the best thing to do is replace the parts you have ordered and see if that fixes it. I hate to jump the gun on anything more complicated.

 

[Chestnut]

I think if the new rotor doesn't do it she'll be visiting the shop. Under warranty for another 30 days or so, might as well use it.

 

[L.B.S.]

I think if the new rotor doesn't do it she'll be visiting the shop. Under warranty for another 30 days or so, might as well use it.

Sometimes it's the weirdest things that can source out to be the problem, alright. That's of no consolation to the poor sod with the problem of course...

I would be pretty surprised if it was anything to do with the rear rotor though, but again, who knows. I think just about every bike I've ever owned has had come and go instances where the rear rotor has done the *scrape* *scrape* *scrape* thing hinting at a: "it's warped!" diagnosis via the wheel being just spun by hand, or slowly turned either coasting or walking the bike. None of them ever were, in the end.

Regardless, best of luck tracking down this pesky problem! Be sure to update if you can and let us know how things are going!

 

[buckshot]

Resetting the ECU might get rid of any electrical gremlins the bike has. I'm not sure of the whole procedure, but I do know you need to completely disconnect the battery for at least 30 minutes, then start it up with no throttle and let it run (no throttle) until the fan kicks in. I think the full procedure was posted on this board somewhere, but I have no idea where it got to.

 

[frozenpoet]

The old Honda's at the second gear problem. Not saying this is, but to test it is to be in second gear and run it low in the rpm then open throttle all that way till redline. If it stays in gear it's good, if it kicks into neutral you have a problem.

 

[showkey]

Resetting the ECU might get rid of any electrical gremlins the bike has. I'm not sure of the whole procedure, but I do know you need to completely disconnect the battery for at least 30 minutes, then start it up with no throttle and let it run (no throttle) until the fan kicks in. I think the full procedure was posted on this board somewhere, but I have no idea where it got to.

While there is no harm in this "reset procedure" there very likely no benefit.........there is no HONDA documentation that this procedure applies to the NC. This procedure dates back to older FI cars that had need for an idle learn feature. Part of the procedure was disconnecting the battery to clear codes and reset ECU.........this also does not apply to the NC. Codes are NOT cleared from memory by disconnecting the battery on the NC. This battery disconnect did clear codes on older models of car and bikes.

The old Honda's at the second gear problem. Not saying this is, but to test it is to be in second gear and run it low in the rpm then open throttle all that way ftill redline. If it stays in gear it's good, if it kicks into neutral you have a problem.

I do not think the original posting is referring to jumping out of gear?

 

[frozenpoet]

I do not think the original posting is referring to jumping out of gear?[/QUOTE]

It only did it once so it might not be a part of the problem as my cbr would do this every once in awhile, but while we're taking stabs in the dark...

 

[showkey]

Rolling long in 2nd in traffic ..........I discounted the jumping out of gear......my stab in the dark