Stratto saw life

Maintenance supervisor

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Venturi size doesn't really matter in regards to the question at hand.
And bypass the strato ports defeats the purpose of them in the first place.
The small venturi draws a thicker fuel mix into the crank case which is then diluted by the strato charge in the upper cylinder , so yeah it does matter. The strato port doesn't dilute the mix until later in the firing cycle, essentially drowning the crank with a rich mixture (lubrication) until the strato charge is introduced.
Theres different size drill bits in the world ,so I'm not suggesting that people grab the hole hog out of their tool box for a intake bypass hole into the strato intake port , think needle bit. It doesn't affect the function of the strato effect other then a super small amount of mix dilution. Which is well documented in some of Alfeetcommand's videos in Husqvarna's design.
 
bwalker

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The small venturi draws a thicker fuel mix into the crank case which is then diluted by the strato charge in the upper cylinder , so yeah it does matter. The strato port doesn't dilute the mix until later in the firing cycle, essentially drowning the crank with a rich mixture (lubrication) until the strato charge is introduced.
Theres different size drill bits in the world ,so I'm not suggesting that people grab the hole hog out of their tool box for a intake bypass hole into the strato intake port , think needle bit. It doesn't affect the function of the strato effect other then a super small amount of mix dilution. Which is well documented in some of Alfeetcommand's videos in Husqvarna's design.
A motor has a specific air to fuel ratio it functions best at. Venturi size will alter carb settings,but not the required fuel to air ratio.
Anything that adds fuel to the strato ports defeats their purpose.
 
Bwildered

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The poster referenced does indeed understand how a strato motor scavenges. However, he doesn't understand how any reduction in fuel usage results in less lubrication going to the motor.
You have anything of substance to add?
I didn't mention anyone in particular, but please do continue.
 
czyhorse

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You are still dealing with a heavy piston that stresses the lower end more than a traditional 2 stroke and the fact they run hotter.
I swear I am not trying to start and argument? But a muffler mod should help with the heat right?

I have heard a lot of complaints because at least the Husky strato saws are all heavier. did they beef up the "lower end" to compensate for the "heavier" piston? The weight had to come from something they couldn't take away or they would have. How much heavier is this poor overweight piston?

because of the increased fuel efficiency Strato saws are here to stay so I would just like to get the maximum out of them I can rather then curse their inferiority.
 
bwalker

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I swear I am not trying to start and argument? But a muffler mod should help with the heat right?

I have heard a lot of complaints because at least the Husky strato saws are all heavier. did they beef up the "lower end" to compensate for the "heavier" piston? The weight had to come from something they couldn't take away or they would have. How much heavier is this poor overweight piston?

because of the increased fuel efficiency Strato saws are here to stay so I would just like to get the maximum out of them I can rather then curse their inferiority.
Muffler mod helps some, but not enough IMO to overcome running leaner than a traditional two stroke.
I haven't been around the new Husky.saws, so I can't say.
 
Motherboard

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I swear I am not trying to start and argument? But a muffler mod should help with the heat right?

I have heard a lot of complaints because at least the Husky strato saws are all heavier. did they beef up the "lower end" to compensate for the "heavier" piston? The weight had to come from something they couldn't take away or they would have. How much heavier is this poor overweight piston?

because of the increased fuel efficiency Strato saws are here to stay so I would just like to get the maximum out of them I can rather then curse their inferiority.
does fuel injection not work then, sure didn't work out well for the 500i, its reported to be an alcaholic and EDITED, is not a strato
as I thought, thanks @huskihl for pointing this out.
 
maowwg

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Wow! Thank you all for the ideas and thoughts. Amazing.

One thing that’s always confused me is that the carb settings I’m at with strato-saws are typically settling at more turns out than the traditional saws. I.e. over 2 turns out vs 1.5 to 2 turns our. Richer

If the strati-saws use less fuel why are the carb settings richer on average?
 
Slotracer577

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Wow! Thank you all for the ideas and thoughts. Amazing.

One thing that’s always confused me is that the carb settings I’m at with strato-saws are typically settling at more turns out than the traditional saws. I.e. over 2 turns out vs 1.5 to 2 turns our. Richer

If the strati-saws use less fuel why are the carb settings richer on average?
Since the Air fuel mix gets diluted with fresh air it has to be richer to make up for the extra air added by the strato system. They are more efficient as less fuel gets pushed out the exhaust without being burned. So less fuel is wasted and they are cleaner in regards to unburned hydrocarbons.
 
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Maintenance supervisor

Maintenance supervisor

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Wow! Thank you all for the ideas and thoughts. Amazing.

One thing that’s always confused me is that the carb settings I’m at with strato-saws are typically settling at more turns out than the traditional saws. I.e. over 2 turns out vs 1.5 to 2 turns our. Richer

If the strati-saws use less fuel why are the carb settings richer on average?
Depends on the saw manufacturer.
 
bwalker

bwalker

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Since the Air fuel mix gets diluted with fresh air it has to be richer to make up for the extra air added by the strato system. They are more efficient as less fuel gets pushed out the exhaust without being burned. So less fuel is wasted and they are cleaner in regards to unburned hydrocarbons.
That's not how a strato charged engine works. The fresh air side is only used to push exhaust out.
The carb settings are larger because the signal is to the carb is diluted.
 

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