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Discussion Starter · #1 ·
So I'm riding at about 35 or 40 mph when I hear a faint tapping; not real fast, like once every second or so. I pulled the clutch in to see if that changed anything but the noise continued. I then pulled the clutch as well as gave some throttle but I could not hear anything of the sound over the engine noise and road noise. By the time I made it home, it was a distinct clanging sound every time I let up off the throttle. It also made the sound whilst coasting. The engine has also seemed sluggish between 3500 and 4500 rpm as well but that may be unrelated. As it seemed to progress as I was riding, I thought I ought to take a look at right away. I could not replicate the noise with the bike up on the A stand. If you have any clue as to what this might be and how long I have and whatnot, I would greatly appreciate anything.



In summary:

Slow Tapping becoming clanging when I left up off the throttle.

Does it with engine off in free wheel.

Sluggish between 3500-4500 rpm.

Oil is clear and no Al filings.

No catastrophic failures noted.

38,800 miles, daily rider





Feel free to ask me questions I will answer them as best I can. I am currently thinking something in the final drive or post clutch transmission is loose but I can't pin it down yet. Thanks.
 

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Does it with engine off in free wheel.



As in when the clutch is pulled in? A rather unusual problem I've haven't seen mention of but it shouldn't be hard to pinpoint as you've already proved you've got excellent diagnostic skills in your post.



Let's see, what still moves under these conditions?



Possibly simple however I would not press the matter by driving it until I gathered more info. Pull up a microfiche of the drivetrain and print it out, take it with you with the bike on the stand.
 

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my first guess on the information provided is that the cam chain[one of its components]have gone south
 

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Discussion Starter · #4 ·
Bandit: If it were the cam chain why would I hear the noise with the engine off and the clutch pulled? If the engine isn't spinning the chain shouldn't be either right? Or could the engine have enough momentum to spin the cam when recently turned off? I must say that was also my first thought, but I looked at what some of the others had said and I can't quite make it all fit.



Marshall: What would you look at first? Or would you just keep looking until something showed up?



Also, I should have mentioned it sounded more like it was coming from the rear end than the engine, but as I couldn't replicate it on the stand, I was unable to locate the area exactly. I wonder if there has to be a load on the bike? Pull the rear brake while it's on the stand to simulate a load?



Also thanks
 

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This is way out of my area thus the reason I sugessted printing out a diagram. I've had so many bikes with clutches in different areas I can't recall this time of night.



Seems to me if you killed the engine and pulled in the clutch the crank would stop rotating in short order, that leave you with "after the clutch" to look at.



Stab in the dark is something related to the starter on back.
 

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Bandit: If it were the cam chain why would I hear the noise with the engine off and the clutch pulled? If the engine isn't spinning the chain shouldn't be either right? Or could the engine have enough momentum to spin the cam when recently turned off? I must say that was also my first thought, but I looked at what some of the others had said and I can't quite make it all fit.
sorry mate,iv reread your origional post,and i cant see that info[early morning here.lol]

i do not understand.....engine off,and clutch pulled in...do you mean ..coasting along with engine turned off,and the clutch pulled in
 

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Pull back the drive shaft boot and check the spline and bolt.
 

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Yeah, clutch or final drive/drive splines.



Personally, I would pull the rear wheel, differential and slip the drive line off the splines at the engine.



this is easy to do and it lets you check the u-joint, splines to engine, splines on the rear wheel to diff. and splines from diff to drive line. as well as rotating the diff by hand to feel if there is any binding or less than smooth operation.



If you don't find anything there, pull the clutch cover and check that next.



I've had more problems over the years with the first stuff then the clutch.

lost one diff, found some bad rear wheel splines, and one bad u-joint.

But that was on quite a few different cx/gl's over the years and a lot of miles.

plus on bikes with unknown maintenance from PO's.
 

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Discussion Starter · #10 ·
Quick update: my rear wheel spins when the bike is in gear but the clutch is pulled. If I apply the brakes, it pulls down on the engine before stopping the rear wheel. So now I'm thinking bad clutch? I am still going to do some kind of inspection of the rear end and drive shaft but it seems as though I am not getting separation between the clutch plates without some help. Red herring maybe? Just thought I would add that for you guys. I haven't had much time to look at it yet, I'm house sitting so I can't get into a deep project here.



Thanks



P.S. Shep, I don't know if the search function accepts onomatopoeia as valid terms or yields useful results. Nonetheless, a search will commence.
 

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P.S. Shep, I don't know if the search function accepts onomatopoeia as valid terms or yields useful results. Nonetheless, a search will commence.


I'm sure you can,"Bang" most words in
 

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With the bike in nutral and the engin off, do not use the clutch, what do you hear? Of course the bike has to be moving. Thought I had better mention that. Standing still you of course would not hear the noise the bike would make.
 

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With the bike in nutral and the engin off, do not use the clutch, what do you hear? Of course the bike has to be moving. Thought I had better mention that. Standing still you of course would not hear the noise the bike would make.


Don't do this for extended periods. you still have transmission gear movement without oil pressure.
 

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gotta be either the reardrive, driveshaft or the output shaft in the trans.... they are the only things that are moving with the motor off
 

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Just For S's and giggles, Jiggle your kickstand
Mine is knocking occasionally... I need a new spring. Almost forgot, jiggle the heat shields on the exhaust. mine were rattling there also...





Yeah, I'm a cornball
 

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Discussion Starter · #17 ·
Hmm loose pieces, didn't really think of that. Should be a quick check...yeah seems like everything is tight. I'm really leaning towards bad clutch or at least a loose something or other in the clutch assembly. Tomorrow when I get back to my own garage I am going to open it all up and see what's what. I thank all of you guys for the suggestions though. I've got plenty of potentials to go through. I'll let you know what I find.
 

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Andrew, I think you are probably on the right track with the clutch. That would lend a hint to the speed issue you mentioned. If it was going tits up (*sorry*) it would affect the power band. Higher revs, more torque. If the clutch was weak, it would not be able to keep up with the power band. Perhaps the clutch springs are bouncing around inside the casing? Busted?



Joel in the Couve
 

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if the motor is off... the clutch would be at a standstill... maybe something really simple... like a screw in the tread of your tire... clicks once a second as the tire rotates... justa thot
 

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Quick update: my rear wheel spins when the bike is in gear but the clutch is pulled. If I apply the brakes, it pulls down on the engine before stopping the rear wheel. So now I'm thinking bad clutch? I am still going to do some kind of inspection of the rear end and drive shaft but it seems as though I am not getting separation between the clutch plates without some help. Red herring maybe? Just thought I would add that for you guys. I haven't had much time to look at it yet, I'm house sitting so I can't get into a deep project here.



Thanks



P.S. Shep, I don't know if the search function accepts onomatopoeia as valid terms or yields useful results. Nonetheless, a search will commence.




from what is mentioned here, your clutch is dragging or never completely disengaging. This could be as simple as adjusting the clutch from both the bottom end (major adjustments) and at the handle (finer tuning)... If full adjustment will not completely disengage the clutch, It's time to dig out the knife and fork, and make sure those plates aren't worn to oblivion




There is also a bolt under the rubber boot at the motor end. It Locks the drive shaft to the motor, and you may have to spin the drive shaft to see it, Pry the boot back toward the rear of the motor, and make sure that bolt is there and tight... If It's missing, I call "BINGO"



Other Spurious thoughts: Biker Mike? Why would turning off the motor disengage the clutch if the bike is rolling in gear? Mine seems to stay in gear (indicating the clutch is working/spinning).



Joel, Broken Clutch springs bouncing in the basket would have a far more noticible effect on shifting etc. than just noise...
More likely, they are worn. (compressed) Honda gives a minimum length service limit and if they are under this, I personally would replace them with the stiffest replacements I could find. I don't mind a stiff handle, and prefer the positive lock up.



Putting the bike on it's center stand and spinning the wheel would confirm or negate the nail in tire theory.



Another thought Guess... While it's on the center stand, you might want to check the rear brakes for things banging around.



I also removed an exhaust the other day that had about a pound of rust flakes in the power box... If you have kids, I hope Jr. didn't put a ball bearing in there




I have found a mech's stethescope ( mine is a brass tube) invaluable in locating the source of mystery noises. I love these guessing game threads and from the sound you describe, I would like to add that it could be the Fan... being on a center stand, the fan is not loaded an unloaded by pressure changes from the bike's motion...



so now, back to the betting window 2$ on every horse in the race.





Anything visual come to mind with the search for onomatopoeia ? LMAO!



Edit: Darn! Cobrahm mentioned the lock bolt above... no bingo for me




Another Edit: Look in the airbox and under the side covers for loose stuff... and please let us know when you get this figured out
 
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