Problematic MS661

[chris zautner]

hd2

What filter is on a new MS880?

 

[big t double]

Hmmm.

your thoughts?

 

[redbull660]

tuning it out = LESS THAN max power.

fix imbalance = close to max power.

Max power = what degree of inflow and out flow is the best? Since ideal tuning is taken care of by the mtronic. So all that is left to do is to test various setups. One end of this spectrum is pretty much fixed...ie. the max flow mod. You can't really change that much. So you stick the max flow on and then start opening up the muffler til you stop gaining power. Then you have the ideal setup.

 

[Trx250r180]

Have you guys tried 50:1 like stihl recommends to take care of the bog ?

 

[blsnelling]

So you stick the max flow on and then start opening up the muffler til you stop gaining power. Then you have the ideal setup.

This saw makes the most power with as much opening as you can give it. Max power isn't what's going to make this saw run right.

This is a tuning issue, plain and simple. Something in the system will always be the bottle neck. Remove one and it will be something else. The problem here is that you can't tune the saw.

 

[blsnelling]

Have you guys tried 50:1 like stihl recommends to take care of the bog ?

No I haven't. I don't really consider that an option.

 

[blsnelling]

your thoughts?

If it flows enough for a 880, you'd sure think it's enough for a 661.

 

[redbull660]

well my testing shows it makes most power with huge openings on small logs and falls behind on large logs. I'm not going to pretend to understand why . But it does. And the fact is, is that you haven't THOROUGHLY tested it on large logs. So your statement of it makes the most power is somewhat false.

Which is why I know my muff modded 661 could get damn close to your ported 661 on a 36" bar 3 back to back cuts on a big ass log. But once you fix the imbalance...


1. the imbalance is the problem with your saw
2. max power = finding the right degree of opening up...that is hard and requires a lot of testing.

what you want to do is, say these mods are good enough and then tune the saw for the mods. The saw is tuning itself ideally all the time...you can't just say these mods are good enough. You have to actually FIND good mods that work with the ideal tune that the saw is finding. ...not what you THINK is good.

 

[big t double]

If it flows enough for a 880, you'd sure think it's enough for a 661.

I think the 661 filter is a little bigger too...no?

 

[redbull660]

If it flows enough for a 880, you'd sure think it's enough for a 661.

and that is another possibility...

661 filter (which is way bigger) may be ideal and your muffler mod may be too much. The max flow may actually not add anything to the system. It may balance your muff mod out. But it may not be ideal and produce max power.

With out actually doing a lot of serious timed testing. It's just a bunch of I think this is best, or it "felt" stronger, or "sounded" better, so it's the best.


serious testing... which you'll never actually do - and so here we are!

 

[blsnelling]

Which is why I know my muff modded 661 could get damn close to your ported 661 on a 36" bar 3 back to back cuts on a big ass log. But once you fix the imbalance...

You are hallucinating again. Go take your meds. I don't see your saw holding 12,500+ with a 36" bar buried in wood. You're talking WAY outside your realm of knowledge.

To further show you have no idea what you're talking about, this has no affect on WOT performance. It runs perfectly.

 

[Moparmyway]

saw holding 12,500+ with a 36" bar buried in wood.

Mine holds pretty much the same as those RPM's now Brad, the hardline bounces around between 11,500 and 12,500 ................I wont pretend to know everything here, I just know what changes were made to mine and what effects those changes brought about.


Before we go diving into rocket science guys, lets see how Brads responds to the Max Flow after he installs it and does the reset.

I think its a matter of the carb response time to vacuum in the intake tract. The Max Flow allows the vacuum to get back to atmospheric faster

 

[redfin]

I'm curious what elevations those with the "bog" are at?

 

[blsnelling]

RB, why are you striking out at me simply because I don't agree with your logic, or rather the lack there of? You have no clue what you're talking about when it comes to mods.

 

[Moparmyway]

it makes most power with huge openings on small logs and falls behind on large logs.

I think that is due to the carb compensating for the increased vacuum the HD2 creates

 

[blsnelling]

Mine holds pretty much the same as those RPM's now Brad, the hardline bounces around between 11,500 and 12,500 ................I wont pretend to know everything here, I just know what changes were made to mine and what effects those changes brought about.


Before we go diving into rocket science guys, lets see how Brads responds to the Max Flow after he installs it and does the reset

Exactly. We don't even know what the cause is yet. As usual, RB, you're again jumping to conclusions before you know the facts.

 

[Moparmyway]

I'm curious what elevations those with the "bog" are at?

I am usually under 300 feet elevation ............. sometimes right on the water

 

[chris zautner]

i'm at 312 ft where my 441 cm bogs

 

[blsnelling]

what you want to do is, say these mods are good enough and then tune the saw for the mods. The saw is tuning itself ideally all the time...you can't just say these mods are good enough. You have to actually FIND good mods that work with the ideal tune that the saw is finding. ...not what you THINK is good.

Seriously? Is that what you call having had two different cylinders and four different pistons in my saw, all for testing purposes. There's no need for you to lash out like this because of your own insecurities.

 

[blsnelling]

I'm curious what elevations those with the "bog" are at?

Only a few hundred feet above sea level.