Here's what I know to be true Matty.
I leave speculation to others.
It's lunch time here.
My 288 is an open bearing on the pto side, no nutin... with crank and cases together. Not much else there.
Better materials of high quality usually improve performance in sever applications involving heat and vicious possibly corrosive, caustic, acidic or degrading (changing) fluids.
Heat just speeds up the process most times.
Cold is whole nuther thing.
Outright friction wear, and combating it, is a science of complete composition control of the correct materials applied accordingly in the correct environment. All BS... just replace it.
Buna is a no go on 20%+ eth gas.
10% eth is a slippery slope with it in fuel systems involving natural or synthetic rubbers.
I run eth pump fuel in my OEM Stihl saws with AM fuel lines... the good ones... they need replacing every year or three. Saws that go out get all OEM everything if it is customer requested. Everyone is informed of what you pay for.. like most places. The carb diaphragm in my saws get soaked in twosmoke oil every time I do fuel lines. Yours would get replaced with your choice of parts available today, new. Eth makes impulse lines hard over time.

Rarely change them on my Stihl saws but I don't cut with dull chains. Does the opposite to fuel lines... they melt in the wet or the tank and hardened outside the line... dry rot as the material is dehydrated. Just keep replacing the line/o ring/bushing or buy the newer lines/o ring/ bushing and don't store with eth fuel period.
Storage is a period of none use for three weeks in this environment here at my stable. Fuel caps and seals seem to be affected very little. I have an idea why but this was about facts.
I'm sure all these old Husky saws could use O ring updates to better materials appropriate for the task at hand. Buna does compress better than most if you use oversized ring thickness. Not always wanted or welcome in certain applications. Others it may be an improvement.
Buna rings are OK imo on fuel with ten percent ethanol or less if if the tool is used on a regular basis. All my equipment is stored with aviation ll100 with or without oil mixes... VP oil is my choice for long term storage and the mill saws... storage is longer than one month.
Tools in storage here come out ready... serviced before storage. I have zero issues with stuffs at start up. Store it with eth and you replace the fuel system.
Husky is all new to me.
O rings have never been an issue... I see few husky saws.
Friction is a *b-word.
If your rubber is exposed to oil, gas, diesel or liquidcoal, methanol or other fuels like JPL stuffs... make sure you have the right "rubber" for the right environment and operating conditions as well as temps.
Remember Columbia?
Some material might be bad in the cold or the heat. Manufactures make choices for reasons based on lots of factors
I'll go away now. The sun is out and these logs don't move themselves.
Afternoon everyone
