New bike (2019), 31 miles. I put a Primary Drive 13 T counter sprocket on noticed it seems noisy. I searched past posts here and see it is not uncommon.
Chain tension on side stand: 1.5"
I put the new sprocket on the same way the original one was: the extended center towards the engine.
Original chain lube- not dripping wet, but has waxy coating.
Checked clearance; not rubbing anywhere.
Noise seems to come from rollers as they contact sprocket at the top.

Please advise

 

1.5" sounds about 1 inch not enough. I have an 09 model, compressed the rear suspension until the counter shaft, swing arm pivot, and rear axle were in line, adjusted for around 1/2" slack then released and measured the slack mid swing arm, around 2-1/2". Better loose than too tight. Chain will not come off.

 

Label on swingarm and manual says 1.4"-1.8" with bike on side stand. The video was taken with no weight on rear wheel and chain was dragging on the top of the swingarm.I could loosen it and try it.

Update: at 1.5" on side stand, the chain feels loose enough, but this morning I checked it while sitting on the bike and the chain was definitely too tight.

 

Also the factory sprocket probably has the rubber damping which helps to keep it quiet and the aftermarket sprocket does not.
The sound seems normal to me.

 

Yeah, more common chain slack measured as the manual dictates will range from around 50mm-65mm...2" to 2.5" or so...dependent on the sprocket sizes you are running. You have to measure at the exact point the manual dictates.

Also, the method of measuring chain slack on the side stand can be a problem. You must be absolutely sure the bike is not "settling" into any of its travel. The bike must be totally "topped out".

Many bikes have a small amount of "static sag"...only the weight of the bike compressing the suspension a small amount. It's best to set chain slack with the rear wheel off the ground. A small hassle but well worth the effort.

Also, the small 13T sprocket can cause the chain to rub the swingarm rubbing blocks more aggressively than the larger sprockets causing more wear and noise on the chain, sprockets, and rubbing blocks.

 

I don't trust any owner's manual on chain adjustment since I had problems with the Zephyr being too tight. Heck they may have cut and pasted that from a 100 G5 for all we know.

Doing the measurement with all the axes in line is about as close to exact as can be had. Once done then get the bike on the side stand or on a center stand, find how much slack mid swing arm and write it down. Then do it at that amount. I found around 2.5 inches to do the job and if you ever looked at the slack in most motocrossers they are probably more than that.

 

My chain was too tight like you said even after following the manual:

Thanks for the help. The chain is straight and the tension is right at this point so I'm not going to worry about it.

 

Tim, that sounds like a really small amount of slack, but I guess the '09 and later models just have different geometry at the links to allow that. Mine is an '06.

 

I set mine to 1.5 on a 2018 model. Make sure you don't have any binding links.

 

Did you recheck it with weight on the bike?