What did I do wrong? Scored 490

[Nutball]

Yes, I have Klotz benol in the 32:1 mix.

 

[Nutball]

Still running strong after 1/2 gallon. Looks like the benol is starting to fill in the scoring. I haven't been too nice to it, lots of long chunking, ripping, and noodling cuts in big wood in place of using my 2188 with a 32" bar, so that heat should help bake in the castor gum. The polished exhaust port doesn't seem to have picked up any carbon yet even though the piston is black.

 

[Nutball]

Actually it has 1 gallon through it, I forgot I'm using a 2 gallon can.

I was checking the tune today, tried tuning my rpm to 13,200. I couldn't really hear a rev limiter, it would reach 13,200, clean up a bit from a severe 4 stroke sound to a much smoother sound. I never tried exceeding 13,200, but even 1 turn richer didn't seem to slow it, but did truly make it richer which was noticeable by the increased torque in the cut, and with enough richening, 4 stroking in the cut.

Just pointing out how rev limiters are either very subtle and hard to hear, or something strange is going on.

 

[LouCi4er]

I thought that 490 was around 13000 limited but i could be wrong.I checked mine,I had it tuned by ear and had set it at 10,900( i set it rich intentionally for break in),then i checked it with a tach and set it to 11,600 but it still 4 stroking heavy,it doesn't clean up under load.I have the impression that i might have a faulty tach( a cheap one) so i ordered another one which should be here tomorrow or the day after tomorrow.Will see.

 

[Nutball]

Well, it's likely rich if it doesn't clean under load, but make 5 cuts, they can 4 stroke a lot till fully warmed up, I 'm sure you know that already. Anyway, mine's modified, so it more easily revs high I guess. I'd assume you could still lean a stock one enough to reach 13,000

 

[LouCi4er]

Well the tach arrived.I had the saw set at 11.160,four strocking heavy under cut.I leaned it to 11.800-12.000,it runs a lot stronger there,it holds around 8.500-9.000 rpm under cut.I left it at 12.000 but i read in the Emission Carburetor Adjustment, Walbro WT-1009 from Echo that the 490 WOT rpms should not exceed 11.400 and it makes me thinking.