Tight/loose spots new chain, sprocket, and bar.

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Vir1dis

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Hello, So I am having issues with tight and loose spot with my chain.
The bar, clutch sprocket, and chain are all new.

I notice the difference when I rotate the chain by hand, and as you can see in the pictures below the chain position can be the same (notice the gold links underneath the 'M') and have different tensions.
There is a fair amount of difference in the tension between the two.(The bar nuts had been tightened, so the bar is not moving)
The sprocket and chain are both genuine Husqvarna .325 and the bar is also .325.
Both the chain and bar are also both .063", all bought from my local Husqvarna dealer.

I also rotated the shaft but pulling the pull cord to check the shaft but didn't spot any bend , nor notice any moment in the shaft (not using any calipers, just by eye and holding things next to it as I spin it).
The spur sprocket has some moment as did the previous one approximately 1mm *see photos. Is this normal?

The saw is a Jonsered 2150
I hope I have included enough information

Thank you in advance.


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I hope you find the answer. I have a very old Husqvarna 50 that does the same thing. I'm pretty sure my crankshaft is bent. I changed clutch, sprocket and bar with another saw and it still does it. It still runs and cuts fine just makes tensioning the chain a little difficult.
 
I've had issues once in awhile where a new bar and chain are a little thicker. Check to see if the chain is dragging on the bar plates in a spot.
I just put some magic marker on the plates and see if they have drag marks.
 
I am not mechanically minded so this probably doesn't mean anything, but I rotated the chain to where there is slack and then I slowly pull the start cord, (thinking it will rotate the shaft) the chain tension was not affected by this.
 
If you haven't done so already, remove the chain and check to see if the nose sprocket rotates smoothly and consistently.
The nose sprocket moves smoothly and all the teeth seem to line up with the line on the plastic. (Tried uploading a video but it wouldn't work)
 

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Tighten the chain up proper and run it for awhile. If all the parts match and are new, it will be fine once the chain goes around a few times
Run it and see what it feels like in 20 minutes. I bet you will be surprised
OK I will try that when I get home later.
I was trying to fix the issue before I put any heat in the new chain.

Run it as in cutting stuff, or just run it at 3/4 throttle without cutting anything?

I will have to check again later to see if the distance of the tight and loose spots are consistent, but here are 2 examples from tight, loose, to tight again.
 

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Would you think that genuine Husqvarna could have the same issue? Because the sprocket is a genuine Husqvarna part I bought from a reputable Husqvarna dealer.
Husqvarna doesn't make their own sprockets, so where the dealer sources the rim would be important . Oregon generally makes the rim for husqvarna but thats not necessarily the case if you purchased it separately.
 

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