Did you try adjusting the chain for a tighter fit? I replaced mine at 30K. I will do chain and sprockets at 60K or earlier.

 

If the sound is at 4,000 rpm ***in any gear*** then the chain is not what is making that particular sound. It is more likely something like "crash bars" resonating or something within the engine.

Having said that your chain could very well be toast and making noise but that would be more bike speed related.


..Tom

 

Try pulling the chain back away from the rear sprocket. If you can pull it far enough to see any daylight between the chain and sprocket it's worn out. For best results replace chain and both sprockets as a set. The sprockets are worn also, you'll be able to see it plainly when holding the old and new together.

 

This is the best advice.

 

I replaced mine at 18k. The chain was making some noise (a clack?) when under load (streatching I suspect), the sprockets showed very little wear, but I replaced them as well. And for what it's worth, it really didn't pull away from the rear sprocket like normal. I agree with V-Tom, if it is a constant noise at that specific RPM, then I doubt it is the chain.

 

I'm siding with V-Tom.

While riding at 4K rpm, put your foot on your crash bars (assuming you have some). See if the sound goes away.

Cool note: If it does it a 4K, it will do it at 8K as well. Such is the nature of harmonics.

If that's the source, you probably have a loose bolt somewhere, or something is cracked. (I've had to beef up and re-weld my old Pat Walsh setup a few times because of a natural harmonic that fatigues the belly pan.)

If it's not crash bars, maybe it's something else you've bolted on.

 

Agree with above that chances are good something else is rattling. In addition to the crash bars, check cell phone/gps mounts (my cradle makes a noise at speed), engine bolt etc.

As for the chain, I replaced mine at 20k. It looked ok but got to the point it was too stretched out. My sprockets looked fine however I replaced them anyway

 

Should you add checking the chain slack? Maybe the chain just needs tightening?

Please correct me if I'm wrong but place a ruler under the chain between the two sprockets. ON THE KICK STAND...measure where the chain is on the ruler then push up to taunt. The difference between the two measurements should be between 0.8 - 1.2 " of slack (according to the owners manual).

 

In my experience, running a chain on the slack side won't cause any sort of whining noise. It will, however, cause a lashing effect if it is too loose. In any case, it can't hurt to check.

 

Front sprocket is the first to go, get in there to check it, and clean out front sprocket area too.

IMO it is better to replace a chain/sprockets (always do them together) at 18k than let it run, have it break, and take out your engine. It is also confidence inspiring to know you have new parts down there.

 

Yup sprockets are cheap, just adds a tiny bit more work is all. :smile2:

 

It's one of those things that sneaks up on you. At 18000 miles everything may feel fine. Put on new chain and sprockets and all of a sudden your bike has tons more power, rides like new.

 

I changed my chain and sprockets at 28k miles. Before that I did a 4000 mile trip and everything felt fine. It went to crap as soon as I was back with unevenly stretched chain. I changed out to a 530 chain and sprocket set. It has to be the best thing I have done to the bike. Kinda kicking myself for not doing it before the trip. Bike feels like new!

 

Re: sprockets, use 36lb-ft on the rear sprocket nuts as befits an M8 thread. The 43.5lb-ft factory spec is excessive and has caused stud damage.