Here's the saw coming apart for measuring the port timing.
The MS261 is here!!
- Thread starter blsnelling
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Very interesting bottom front AV mount. It should prove very interesting getting the handle back on.
The upper spring does not look to be replaceable. It does have an internal cable that limits its travel.
The upper spring does not look to be replaceable. It does have an internal cable that limits its travel.
the westspartan
Addicted to ArboristSite
That would be fun, except the 441 I did is in NYIt responded tremendously. I was very pleased with it.
You can send that 576 to me
I'll run it for ya against that 441.
That bump in the corner of the intake port is to hold the bottom ring end in.
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Port timing is as follows.
Exhaust 103° ATDC
Transfers 121° ATDC
Intake 73° BTDC
Blowdown 18°
Squish without gasket .020" on three sides, .018" on the intake side.
Porting timing without gasket.
Exhaust 105° ATDC
Transfers 123° ATDC
Intake 76° BTDC
One interest point...the transfers are sloped much more than normal. They start opening at 121° ATDC on the intake side and angles to 136° on the exhaust side.
Exhaust 103° ATDC
Transfers 121° ATDC
Intake 73° BTDC
Blowdown 18°
Squish without gasket .020" on three sides, .018" on the intake side.
Porting timing without gasket.
Exhaust 105° ATDC
Transfers 123° ATDC
Intake 76° BTDC
One interest point...the transfers are sloped much more than normal. They start opening at 121° ATDC on the intake side and angles to 136° on the exhaust side.
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I'm thankful that we have a brand new toy to tinker with.
I'm thankful that we still have a Free Enterprise marketplace that facilitates creativity and competition and the freedom to shop around and choose whatever product we want to buy.
When the fat lady sings, the only colors that really count are red, white and blue, not orange nor popsicle.
God Bless America By Kate Smith
http://www.youtube.com/watch?v=r26_CSzk3Xw
I'm thankful that we still have a Free Enterprise marketplace that facilitates creativity and competition and the freedom to shop around and choose whatever product we want to buy.
When the fat lady sings, the only colors that really count are red, white and blue, not orange nor popsicle.
God Bless America By Kate Smith
http://www.youtube.com/watch?v=r26_CSzk3Xw
Trigger-Time
Addicted to ArboristSite
That piston is wild looking!
TT
TT
Standard fare for a strato saw. They are strange indeed.
Thankfully, I had no plans to do a popup on this saw. The crown is ony about .110" thick above the top ring.
Nice to see the Germans are getting a sense of humor! :hmm3grin2orange:
:hmm3grin2orange:
porsche965
Addicted to ArboristSite
Pretty darn exciting if you ask me. Dealers don't even have these on their shelves and here is one in Ohio being disected!
Don't get more cutting edge than this!
Thanks Brad.
Don't get more cutting edge than this!
Thanks Brad.
Pretty darn exciting if you ask me. Dealers don't even have these on their shelves and here is one in Ohio being disected!
Don't get more cutting edge than this!
Thanks Brad.
Who needs a stinkin' warranty!:hmm3grin2orange:
In this pic you can see how progressive the transfers are front to rear. I think I understand what they're doing here. By opening the intake side first, the pressure is higher on initial opening, and all of that pressure is directed to the back of the cylinder, and then progressively moves forward. I'm thinking this is an attempt to more positively purge the exhaust from the cylinder. Instead of opening the transfers all at once and "blasting" the exhaust out, it's being pushed out from the back forward. Make sense?
Here you can see where I've marked the skirt edge, and then where I intend to make the port. I'm only leaving 1-1 1/2 mm of coverage.
This is a better shot to show you the bulge in the intake that holds the lower ring end in.
This is a better shot to show you the bulge in the intake that holds the lower ring end in.
Tzed250
Addicted to ArboristSite
In this pic you can see how progressive the transfers are front to rear. I think I understand what they're doing here. By opening the intake side first, the pressure is higher on initial opening, and all of that pressure is directed to the back of the cylinder, and then progressively moves forward. I'm thinking this is an attempt to more positively purge the exhaust from the cylinder. Instead of opening the transfers all at once and "blasting" the exhaust out, it's being pushed out from the back forward. Make sense?
That is standard two-stroke scavenging. That is why they are called loop scavenged. Up the back, over the top, and down the front.
.
I've just not seen it near this accentuated this much.
porsche965
Addicted to ArboristSite
You aren't right! But that is what makes the best "The Best"
That comment goes for all the Out of the Box Guys of AS.
Erick
Addicted to ArboristSite
I was kinda looking forward to running that thing in factory form on Saturday, but somehow I knew it wouldn't make it more than a couple day's without being molested. 
