New Chain Question

[busastrom]

First I wanted to wish everyone a late happy Thanksgiving.

When I was replacing my back tire this evening, I was taking a look at my chain and noticed that the length was at the limit (12.5 inches) so I know it needs to be replaced. My question for you all comes from what I started the bike up on its stand.

Everything seems to be working great except when I hit the throttle hard. I hear this small bang from inside of the engine and again as soon as I let up on the throttle hard. If I do a slow run up and slow run down, no bang. Now I know this could be a lot of things but could this be the chain missing on the engine sprocket since it is at the edge of tollerance? From what I could tell, it was around where the sprocket in the engine is located (maybe that is wishfull thinking)


Thanks for any ideas.

 

[kromdom]

since you have already determined that the chain needs to be replaced, my vote goes to changing it soon. then see if the "bang" goes away. best of luck.

 

[Dozerdriver]

Is the chain adjusted properly... try riding it and see if the noise is still there. It could be the teeth not going into the chain just right but not sure. Seems you should inspect the front sprocket for wear if it is that. Good luck..

 

[dnstommy]

Isn't that banging the chain skipping? I had the same issue at the track on a new chain. After I tightened it, no more noise.

 

[mike1180]

My guess is the chain.
Replace it and see if it is still there.
JMO

 

[Mythos]

My question for you all comes from what I started the bike up on its stand.

If you ran the bike in gear on a pivot stand there would be no load on the suspension/swingarm at all and a rhythmic clunk/jerk would be normal. The chain would be at its loosest with the suspension wide open.

If you ran it on a spool stand, I would imagine that would be the same as riding on the street. Seems funny that it does not clunk when you ride. If you are all out of stretch on the chain, I would replace it anyway.

 

[Frank Jones]

Is there a shock absorber (cush drive) in the drive line? the noise could be from this.

 

[Tufbusa]

Sounds to me like the cush drive may be your problem. Put it up on the stand, leave the tranny in gear and turn the wheel back and forth. Watch the sprocket hub to see if and how much movement you get. If there is any movement in the hub, pull the wheel and inspect the cush drive rubbers!

If your chain is worn out and you've never replace the rubbers, I'd guess they need replacing whether this is your "Clunk" problem or not.

 

[GoldenChild]

on a stand thereis no load so tranny will make clunk,2 piece stock locker will bang.repace chain and sprockets if at limits..lmk when ready alwaysgot a great chain sprocket deal going.

 

[BIKE DUDE]

Do you know how loose the chain would have to be to skip over the front sprocket.??? Highly unlikely unless you've NEVER adjusted it. JMHO I'd look elsewhere for the noise but I agree with GoldenChild that the drive train with no load on it would be apt to be a little bit clunky and considered normal.

 

[busastrom]

Ok sounds good. I will go ahead and ride it tomorrow and see if the clunk is still there. I have always watched the chain to make sure it was not too tight/loose. Since we are so close to the end of the riding season, I will probably just replace next year.
Ill let you know how the ride goes tomorrow. Thanks all for your input.