wyk

Quoted Figs from respective manufactures ...power head only ...

 

660 7.5KG

 

390 7.1KG

 

so not much in it really , Stihl a tad heavier.....

I don't have the weight on a 660 - but it isn't much more than a 390/385xp in my experience - just a boatload more vibration.

For felling all day, I would prefer a ported 390 for the AV over either, and the fact it weighs 2lbs less than a 394/395. On the ground, or as an occasional saw, it doesn't really matter much.

Bud of mine uses black light(UV) paint or ink, and covers it with clear nail polish or some sort of similar stuff if I recall. Hit it with the uv light and it shows up clear as day and doesn't look marked at all otherwise.

A circlip has come out at some stage and scored the transfer side, doesn't look too hot to me:thumbdown:

If ya ask me - it looks like it was put together without circlips in the first place...

I've drilled it just wondering if anyone had any success with any other mods with it

Advancing the timing makes a big difference as well.

It's a very poorly made, and likely unsafe to use chainsaw. Personally, I also would chunk it into a skip. I wouldn't even bother to give that to someone unless I happen to not like them much.

I'm missing pitch and gauge info in that search system!

It's Europe, Niko - stihl is 63, husky is 58 - always and forever

No doesnt impinge, port has been beveled, it has nothing to do with lubicating the ring oils in fuel mate it goes everywhere the fuel goes that tiny piece of metal is not gonna oil the ring anymore than any other part of the bore, compression ring doesnt touch it, thats still lubricated

So long as it doesn't enter the intake port, you're golden(and the port need not be beveled at that point). I was worried it was one of the 38's that had the tonsil where the ring rode on. Without it, the ring enters the intake port, which means it may wear or get caught without a bevel. The tonsil also keeps the oil on it, if the ring enters the intake without riding the wall, it will slick the oil on the bottom of it onto the intake port floor, which you would rather it be on the cylinder walls, really. But it seems your one avoids all that. Cheers!

Yep opened the baby right up, that nothing to do with keeping ring in check mate

Does the piston ring impinge upon the intake port on the model you have? If it does, and you've removed the overhang, make sure to bevel that port. It is not only to keep the ring in check, but also to keep the ring well lubricated.

Pretty much my thinking as well Wes, unlikely to have bad seals or pipes at this age!

Wish I could say the same about myself.

Forgot to add, on a new saw, sometimes the L screw setting can have that effect. Make sure the idle and L screw are adjusted well. Set the idle to where it's healthy, but not moving the chain, then turn the L screw open until it starts to stall, then back off 1/4 turn and blip the throttle to make sure it's responsive(a rich L screw can have the effect you are describing). Make sure the saw is still happy with the throttle, then go cut and see how she does. Make sure the H screw isn't too lean as well.

I hope you didn't grind out the tonsil if it had one on the intake side? That's to keep the ring in check.

If it's 4 months old and the fuel tank has more than a puddle in it when you are doing this - IE it is easily reproducible, you need to take her to a dealer for inspection under warranty.

Can you get us a video?

33.9mm inlet 33.7 exhaust - the skirt has a scalloped edge and isn't straight - I believe the Meteor one has straight edges and is a lot wider!

Wow, that meteor is huge. I'm gonna go clean up that cylinder now, I reckon.

I think I have one - you need the width across the skirt - the "chord" length I guess??

Pleez And thanks for that, bud!

I did one fir a milling Doctor on this site, there are things you can do.

 

On the one I did, it had very uneven uppers so I leveled and reduced blowdown time.

 

The ports can't be widened touch due to the width of the piston skirts so take the previous comments with a pinch of salt...sorry Eddie:blushing:

 

I think from memory, that the base gasket can come out but measure it!

I forgot to ask - does anyone have an 064 piston laying about can measure the diameter to the skirt edges? I have a feeling my ports may be a bit too wide on this HyWay to save it and use an o64 piston.

The 341 was a downtuned 361 (smaller carb, nothing else), completely identical otherwise. From memory 4 vs 4.6 hp. I could never understand the point; why would you have a 341 when it would leave you wondering about having more power? Surely not a few quid?

Marketing is finding new niches to sell products to. At it's finest, it is creating a niche that doesn't even need to exist, and then convincing a consumer that it is a product they must have.

Husqvarna are not immune. In fact, they have it mastered even better than STIHL with their 555 and 365xt as slightly detuned pro saws at the factory.

038 is funny as it has the piston ring stop pins on either side of the exhaust port plus the piston skirts aren't very wide. May not be much room to do any widening.

Modding the timing gives similar results to adding width. The only problem is you do so on a 38 at the sacrifice of possible torque if you open the exhaust earlier, and you lose some intake velocity adding timing there instead of width, which again is lost midrange torque. Having said that, just adding some intake timing and exhaust alone, with a decent muffler mod, and you will see a big difference throughout the entire power band.

Hi Wyk,

Yes it is synthetic ester, low ash , low smoke, high protection , so will it be ok?

I was told by someone a few years ago that decent mx oil is a very good quality oil to use in the saws,

Josh

 

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Says JASO FD on the back there, so prolly good stuff. It claims to be tank premix compatible, so should work fine. I can't say much more as I haven't used it myself, but others on some forums have said it works for them. Follow standard chainsaw mix ratios and you should be alright. I run all mine at 40:1.

The only caveat with SIlkolene is to make sure it is synthetic esther and not castor or kart or racing oil. Avoid castor in a chainsaw unless you tear it down often.

thats a nice bench well done :thumbup:

Thanks, Bud. Just don't ask me to move it!

Here's my first attempt at outdoor furniture:

Can I draw your attention to the heading of this thread?. "Semi pro saw choice". What I suggested is a semi pro saw. You seem to have suggested 2 pro saws. Are you finding this a bit difficult?

The MS391 you suggested costs the same as a 550xp and 555, and has a lesser build quality. The 555 is the better choice by far with more power and nearly 2lbs less weight. This, I am sure, you would find difficult to deal with. Without Stihl's policies that protect it's dealers with inflated prices on homeowner saws, the Husqvarnas are the better choice for the consumer. The OP included.

Some folks have asked me if I could explain what a saw does when it detonates. I happened to have caught it on video. Since this is a lil cheaper ECHO, I decided to run it a bit and show folks what to expect with severe detonation on a saw since I had little to lose.

SM,

You have a lot of great options in that price range. I would go to the local dealers and heft the saws mentioned to see how ya feel about packing such a thing.

I suspected the Scot would not return after his post, so I may put this point to you - the MS391 will sell for nearly the amount you quoted, yet is heavy for it's displacement(nearly the same weight as a 70cc professional saw), have less power at that price point, and with a plastic chassis VS magnesium. I would ignore his suggestion.

In the 50cc range: Echo 500ES(if you can find one, they basically sold out), Husqvarna 550xp's, 555's, 545's, Dolmar 5100 series, and the Stihl 261CM should all get the job done in that price range, go easy on fuel, be lightweight, and last a long time all being professionally built. The 555 is a particular bargain and is a 59cc saw to boot.

If I were you, I would go with whichever one of these you fancy that your local dealer has.