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Discussion Starter #1
So this noised has been slowly getting louder and louder. It comes from the output shaft on the transmission and can be heard from the opposite side of the bike like its radiating right through the engine. Here are some videos of what it is. It isn't normal chain noise its the knocking you hear. Let hear yoour thoughts.

This first vid is freehanding the tire going forward at first, notice when you go backwards there is no noise. I would believe this would rule out problem w/ chain sprocket


The second vid is in 1st gear. when riding the noise goes away when accelerating but gets much worse while decelerating. Also while braking the rear the noise goes away.

Thoughts comments? Reccomendations?
 

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sorry I cant help but I'm reminded of this ...:icon_lol:
 

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Possible tranny but I'm guessing not. Plenty of fools on here have run their bikes out of oil, coolant, Burned up clutches bla bla bla. But none of them have ever ruined a tranny.

Your knocking sound matches the timing of the chain noise perfectly. When you roll the tire forward, you put slack in the top part of the chain, same when you let of the throttle while moving. Either something is not tight with the chain guide or your chain is too loose and hitting something that its not supposed to. I can't say for sure but I'll bet you find your problem on the swingarm or somewhere the chain runs... not the tranny.
 

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Discussion Starter #4
When i first started to hear the noise i ruled it out to be the chain rubbing etc. my chain tension is dead on as well, and i'm meticulous with cleaning lubing. I'll also do another vid tomrrow on the timing of the chain. its looks like it is timed exactly with the chain but for the life of me turning it very very slowing, the intesity of the knock remained constant and was off from the chain contacting the sprocket. Tomorrow i will remove the chain from the front and see if it still makes a noise. It has progressively been getting louder over the last 4k miles. I also noticed if you put your ear to the clutch case you can hear the knocking through the cover(engine off of course) i'll let you know what I find. I'd rather not have to replace any hardparts, we'll find out tomorrow.
 

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Discussion Starter #5
sorry I cant help but I'm reminded of this ...:icon_lol:
Hahahahha, thats great! Typically if i have a vibration or small noise i dont' really fret much. This one however has been increasing in intensity so i figured i'll try and really get to the bottom of it. Going slowly around parking lots etc it so loud i can hear it with helmet and noise canceling earbuds in.
 

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When i first started to hear the noise i ruled it out to be the chain rubbing etc. my chain tension is dead on as well, and i'm meticulous with cleaning lubing. I'll also do another vid tomrrow on the timing of the chain. its looks like it is timed exactly with the chain but for the life of me turning it very very slowing, the intesity of the knock remained constant and was off from the chain contacting the sprocket. Tomorrow i will remove the chain from the front and see if it still makes a noise. It has progressively been getting louder over the last 4k miles. I also noticed if you put your ear to the clutch case you can hear the knocking through the cover(engine off of course) i'll let you know what I find. I'd rather not have to replace any hardparts, we'll find out tomorrow.
I didn't want to recommend removing your chain ( some ppl put like 5 quarts of oil in their bike cause they're not able to look at a sight glass to see if it's right) but since you've shown that you're not an idiot, I'd pull the chain and spin the output shaft and listen.

Only thing I can think of in the tranny is a bent shift fork but I think it would make noise in both directions. I'm going to remain positive and say it will be something easy to fix.
 

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One thing i noticed in the videos is that the bolt holding the sprocket on seems to rotate off center a little.. not sure what this means (shot bearings maybe) but I think this might be a symptom of the cause to the problem..

Dcope deff knows better then me though, but maybe he didn't notice what I noticed

good quality videos BTW
 

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Think about this: if the sprocket shaft (i forget proper terminology) is loose from something undoing itself, or more likely from a bearing failed, then that might be an issue. Considering that applying the brake stops the noise, this COULD support my theory... if applying the brake pulls the sprocket shaft (sprocket side) flush with other gears - from the chain yanking on it - then it might indicate a bad bearing.

Also, in reverse motion aren't there parts up into the clutch area, etc... that only function in forward motion? If this is true, it could explain why the reverse motion pulls the sprocket shaft back into place better (the same as when applying the brake).

The fact that you're not on the side of the road as we speak shows that, at any rate, your problem is minor... for now anyways. So maybe consider the/any shaft and the chance that a bearing has been spun. These bad boys are high-rpm units, so it wouldn't surprise a person at all if the tranny might burn a bearing or something.

How many kms on the bike? Perhaps use that as a deciding factor as to whether or not you should order new bearings/seals and get busy with the whole thing. I might be crazy and sounding like i'm BSing, but i think i have some valid points.

Good luck, and no matter what, you're okay for the most part because you can still drive it; meaning the parts might be small, mostly intact, and easily replaced. Hopefully...

Dave
 

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And about the sprocket nut being off-center... if a person takes off that bolt, they would see that the sprocket is centered regardless because of the splines on the shaft. The bolt is inconsequential.
 

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Discussion Starter #11
There is 28k miles on the bike, oil changes are done religously. I notice the bolt being slightly off center, but haveing the camera on the tripod throws out the theory that the sprocket is off center as you can watch it. ima get busy on it here in a bit and do some testing, i'll keep you updated.
 

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And about the sprocket nut being off-center... if a person takes off that bolt, they would see that the sprocket is centered regardless because of the splines on the shaft. The bolt is inconsequential.

I was basically saying what you said in the post below mine.. the sprocket bolt is attached to the shaft so if the bolt is slightly wobeling then the shaft is slightly wobeling which leads to my initial thought of shot bearings,, exactly your thought,, I just mentioned the bolt and not the shaft because the bolt is visible in the video
 

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The head of that bolt running out is expected. The way that shaft is produced almost guarantees the threads to have some runout. Not only radial but angular also. Don't make me explain this but the bolt head is a non issue.
 

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Discussion Starter #14
Found the problem

well i think i found what my issue was. Like my dad says, No sense in being stupid if you don't show it once in a while. Rather than biting my tounge, I would rather educate the community on my mistake. I pulled the sprocket off and put the chain aside. To that I found that there was some play between the sprocket splines and the output shaft splines shown here.

I've read other testimonies that when installing the driven front sprocket, it was noted that the sprocket seems to be slightly narrower than OEM and the sprocket bold/washer does not tighten down on the sprocket but rather on the output shaft. This allows the sprocket slight movement side to side. I would believe that this is also why the splines are worn so much, by allowing any movement it is letting the slap around and wear.

Side note: Is this correct amount of play for the trans in gear?

What my mistake was: When installing the Driven front sprocket,(mine is 45T) be sure that the longer shoulder is facing the transmission. On my sprocket, it is the side that has the part number, the tooth count, and the driven logo. I had all the information facing out. When I installed it, it looked like the chain was tracking straighter with it installed this way(which was obviously wrong). Also i'm not very satisfied with the wear of the splines. I'm going to attempt to find a washer with an ID that will slide around the splines and take up the slop from side to side so the sprocket bolt and washer hold it tight. I will also be replacing the front sprocket so it doesn't continue to wear or damage the output shaft splines. I figured i'd try flipping the sprocket and it was day and night difference. i hope someone that is installing a Driven sprocket can find this and learn from my mistake. Thanks Dcope for your help, as well as others that had input!
 

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I will replace the sprocket. What about all the take up in the trans, when in gear?

That is normal,, the 'take-up' is part of the reason why cars and bikes 'chug' when in low gears at low rpm's
 

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The tranny part looked good to me. You have backlash in 4 gears and a clutch till you get to that shaft. That amout of backlash on that shaft looks normal.
 

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Sorry, I've had small amouts of time to just say something quick but not really explaining.

Replacing the sproket, As the spline on the sproket has been wearing out... the noise from it has increased. So basically I said to replace the sproket cause I think its too late for a washer to keep your sproket tight. You need a good splind and then adding the washer, you shouldn't have any problems. I know you wern't debating that, I just wanted to say it in case someone else searches this post, they'll know that they need to replace the sproket, not just doing it just in case.

I don't like to boast when I'm right, but I'm sure you won't mind. This is a lot better than ripping out the motor and fixing the tranny.
 

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Discussion Starter #20
No problem man! I was hoping you would have chimed in on this one and glad you did. Its always that second opinion, and a well educated one at that, that makes troubleshooting a breeze. Thanks again.
 
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