Huztl MS660

[frag-88]

Another mysterious thing about farmertec 660 56mm bore.
Saw 2 times start with reverse rotation of the crankshaft)))
I did not measure the compression after assembly, but without decompressor saw not really start ... The cylinder is 1 gasket Farmertec ...

 

[davhul]

If I read that right I don't believe it could start and run backwards. The recoil would have to exit front of the cover. It's a 90cc saw so you have to pull it like your trying to rip the rope out.

 

[frag-88]

It turns out that too early ignition. Saw factory in the opposite direction and the smoke coming from the air filter))

 

[Definitive Dave]

IMHO, a 9-pin rim has no business on a 600. In wood of any size, a 7-pin will work best.

I run a 10 pin on a few of mine but they aren't for firewood

 

[weimedog]

I like the 9 pin for the 56mm saw & 22 nch minus wood. All I have is hard wood and its got plenty of beans to pull that 9. I would recommend an eight pin if any one asked or if a person didn't have time to learn finesse....

 

[weimedog]

To those where it kicks back hard, might want to check to see if your fly wheel hasn't moved and or check the gap between the flywheel & the ignition. For a while on this thread there was a rash of flywheel/key way issues probably related to how tight the flywheel nut was tightened, but was a trend on this thread a while back.

 

[Racr350]

I run a 10 pin on a few of mine but they aren't for firewood

Damn...that thing must absolutely rip.

 

[davhul]

Racr what mix and ratio you like using

 

[Racr350]

Racr what mix and ratio you like using

32:1 with Amsoil Dominator. Never had a Scuffed Cylinder..

 

[davhul]

That's good stuff. I've been running e-0 90 with 40:1 Kl200

 

[Racr350]

That's good stuff. I've been running e-0 90 with 40:1 Kl200

Cant go wrong with Klotz products. Guess I forgot to mention fuel type...its 91 Ethanol Free.

 

[davhul]

I got a vid earlier and it runs good. I was happy. You might can hear it's far from stock and I was running a pretty aggressive chain. I'll upload when I get back later.

 

[Johnnybar]

It turns out that too early ignition. Saw factory in the opposite direction and the smoke coming from the air filter))

Guess you mean it fired BTDC, like the old hand crank cars and tractors that would break your arm if you weren't careful, and as a result kick started itself into reverse running? Curious how many parts of the recoil starter had to be replaced? Sounds like a "make sure your decomp valve is in perfect order" training film to me.

 

[davhul]

This is one vid I uploaded. It ran pretty good and held rpm as well. The tune held where ever I set it. Here it was at 12,300 and I could tell it was pretty fat but Later in the day i found it likes to be around 13-13,200 And still strokes good. I might run it tomorrow and put some more time on it then check compression. As you can see I short pulled it on the restart. You have to fully commit and should have the brake on.

 

[Racr350]

Looks like a strong runner and a hell of a noddler! That restart reminds me of my build. You definitely have to be aware of whats on the other end of that recoil when you pull. So your free rev rpm is a tick over 13k? Seems like thats what these buids like to run at. Id be interested in what the Piston Wash, i.e. Scavenge Pattern, and Plug color looks like after a hard run at that tune.

 

[davhul]

I didn't mind it being on the fat side that was the first real run and at 12,300. For the 2 cuts I did at low 13's I could tell it woke up. I'll find the high end of the tune once I run some gas through it. The other 2 saws I stopped the tune around 12.8-13 because that's all they wanted. I suspect I may leave this one in mid 13's and still sound safe.

 

[weimedog]

Yup, last two years taught me 12500, was fat, 12800 was safe for MOST of these MS660's, 13000 was crisp. Bling saw is at 13500. Had to put a carb on that could deliver enough fuel consistently to support that tune. Now have dark brown plugs on Bling Saw (not a standard 54 or 56mm build! ) at the 13400-13500 it is set at..on to the next set of mods. Need more transfer x-sectional area..

 

[davhul]

Do you plan on raising the band and dropping the cylinder to get it up around 190 psi? Have you thought about trying that mmws cylinder

 

[weimedog]

Do you plan on raising the band and dropping the cylinder to get it up around 190 psi? Have you thought about trying that mmws cylinder

Not on the 56mm cylinders, pretty much all I did with them 2 year's ago is clean up the ports. I guess that intake horn I got last year is a mod. To be honest those 56mm's are hard enough to pull over as it is. Even though I thoroughly understand the importance of compression & squish relative to efficiency....a man has to know his limitations. My 56mm "bling saw" is at .034 squish so it wouldn't be hard to take another .010 and wouldn't add enough to the free port to matter. "Bling" saw has turned out to be both useful and fun, even though its not "optimal" so I'm going to just run it for a while as is. On the 54's thats another story, as a few have come with .050+ squish and I have put them on the lathe to get them in the mid .020's . BIG difference BTW definitely worth doing along with a clean up & adjusting of the ports. An obvious difference. The good news is unlike the Husqvarna's, you can take a LOT off the base w/o making it too thin.

 

[davhul]

Sounds good. Which 54 has the squish down to mid 20? I'll have to check out that vid I bet it runs strong