91 cc's Oh Yeah!!!!

[PogoInTheWoods]

Now there's what I'm after. Rev limiter - blinky red light - what other tips can someone give so I'll end up with a GOOD saw. Is the MS660 the best one?

The MS660 is the newest one between the 066 and MS660 and some would say a bit choked up stock by comparison. As for the 066's, there were basically three versions if I'm not mistaken (and I'll most certainly be corrected if I am). The original "flat top" which was essentially a big bore 064 and which also had a smaller crank than the later 066 and no de-comp. The "red light" which was the rev limited version of the "flat top", but with the larger crank (I think). Then the 'round top".

I'm rebuilding an older flat top from the ground up and can't wait to get it running, but it's presented some challenges along the way and I've made a few mistakes along the way as well -- which tend to be expensive when rebuilding a 90+cc saw! I have the smaller crank version and am not concerned about it at all, though they have been reported to be prone to breakage in their intended production environment, hence the larger crank in later versions ... anything later than X 33-917-065.

There are other variations of the 066 with slight differences like the Arctic version and and Aus version, etc., but the basics are pretty much the same across the board for the most part.

One bad-ass saw any way you look at whatever 066 version ya may have.

edit:

I'll qualify the above by saying the info provided is purely based upon my experience rebuilding my own 066 and has been gleaned from the IPL's and service manuals I've used to date...not to mention plenty of info from this site.

No experience with a MS660 myself, but Wiggs seems to have summed that up from a position of personal experience.:hmm3grin2orange:

 

[wigglesworth]

Late model 660's are turds. Plain and simple. They are gutless compared to the early 066's. They can be made into runners, but it takes some work....

 

[xxl]

Yes the late 660s are a bit restricted but a Dual port should help

 

[MCW]

The Australian delivered 660's aren't restricted but I feel sorry for you guys in the US under the EPA's thumb.

 

[xxl]

The US muffler sucks

 

[wigglesworth]

Yes the late 660s are a bit restricted but a Dual port should help

Yea, the mufflers are choked up, but that ain't the half of it. Smaller carb jets, less ignition timing and horrible port timing for a work saw.

 

[northmanlogging]

I hear tell of a ms661 in the werks or is that just a rumor? if its anything like the 461...:msp_w00t:

Although I think if I do go with a bigger saw I'm going all out with a ms880... the war dept ok'ed it as long as I clear enough profit this year...

 

[Nardoo]

I have seven of this series including a couple of strong modded saws from some knowledgable gents on this forum - the rest are Oz 064's, 066's and 660's. You know, they vary a bit but gosh, they all cut very well. Aside from the ported saws the most surprising powerwise is an early low hour flat top. It will outcut my 288 and 390.
Wiggs and Randy know about the best port timing on these saws and the Stihl designers did too apparently. I am thinking your EPA requirements have strangled later versions.
If you are wanting a saw with good power & easily available parts stay with a poly flywheel 066.

 

[excess650]

Nardoo finally mentioned the poly flywheel. The earlier versions used the aluminum flywheel, had the smaller crank ala 064, but had the best cylinder (non-decomp). IIRC, the "wrap" version sold in the states had the larger clutch cover and higher volume oiler.

 

[nstueve]

I'd need a saw porting pro to drop a knowledge bomb here, but I've heard the early flat tops were the most powerful b/c they had the most aggressive port timing..? I've seen 066 flat top pistons and cylinders go for $200-$300 on ebay but that is possibly b/c they fit in the 064 which is lighter than the 066.

There were also several different styles of air cleaners. The older flat top had a 2 piece air filter system in back and the newer 660's had one large plastic cover for the air filter box. Not sure if either has any advantage or disadvantage or if you can convert back and fourth or not...

 

[056kid]

Yea, the mufflers are choked up, but that ain't the half of it. Smaller carb jets, less ignition timing and horrible port timing for a work saw.

So is that why its so popular?

 

[wigglesworth]

So is that why its so popular?

You ever ran a red light 066?

 

[nstueve]

the intake boots aren't really the widest i've ever seen either...

Most of all these problems can be fixed by a good professional chainsaw modder... The real problem is why should you have to fix a new saw to have it run like you want.

 

[old-cat]

Well, according to the info so far, the one I rebuilt must be one of the best. Late? 066, polly flywheel, wrap handle, no red light. It seemed like the timing was a little slow.

 

[056kid]

You ever ran a red light 066?

I've run pretty much all of them but I know which one I can go to the store and buy today so that's the one that I have to use. And after its been ported I don't consider to be that much of a slouch.

 

[redoakneck]

I modded the muffler and put a dual port cover on it, put a .074 high jet in place of the stock .062 ($5), and changed over to the high output oiler. Also added an hd-2 air filter with an after market outer wears dust pre-filter.

Mine pulls a 24" bar with an 8 pin NO PROBLEM

 

[old-cat]

I modded the muffler and put a dual port cover on it, put a .074 high jet in place of the stock .062 ($5), and changed over to the high output oiler. Also added an hd-2 air filter with an after market outer wears dust pre-filter.

Mine pulls a 24" bar with an 8 pin NO PROBLEM

My customer has a 36" bar for this one but the chain is dull so I put my 24" bar/ full comp RS chain and 8 pin sprocket. It pulls it just fine and rips the chips out like crazy but it don't reach maximum. I put a 7 pin on it and it did much better! I can push that thing hard now and the rpms stay up to maximum power.

 

[redoakneck]

Mine has full comp RS and an 8 pin and it will hold 10K in the cut pulling up on the rear handle and the dogs dug in. It has 175 psi.

This was dry redoak wood, not the softest out there.

The muffler is really opened on mine, tached to 13,200 rpm

 

[angelo c]

Theres only one bad 066/660... The one thats on your bench and not completed yet. Slap a dual port muffler on any one of them and the differences are minimal. Who sharpened the chain would be the biggest difference maker.

 

[514mach1]

All these variables and downsides vs. upsides. I say just find a good 394 or 395 husky and end up very happy.