What 2 Stroke?

[Haironyourchest]

Stihl HP Ultra at 40:1 = never worry about it again (if your machines have not already been damaged - remove exhaust muffler and check cylinder bore for scratches)

[smithers1603]

Thanks for the info, I thought all 2 stroke saws where the same, I will have to start and read up on things before using them[emoji106][emoji15]

 

 

Sent from my iPhone using Arbtalk

[Joe Newton]

Stihl HP Ultra at 40:1 = never worry about it again (if your machines have not already been damaged - remove exhaust muffler and check cylinder bore for scratches)

 

 

40:1 is unnecessary.

[TimberCutterDartmoor]

40:1 is unnecessary.

 

[Haironyourchest]

Maybe, but can't hurt....

[spudulike]

I personally think that 40:1 makes sense as modern saws use less fuel, less fuel means less oil so if you pop more in, it will do no damage and may help the engine stay cooler, keep bearings in one piece and help stop seizure.

 

It is my personal opinion and is what I would recommend but what do I know:sneaky2:

[Stumpy Grinder]

A local saw docter told me to only use Husky oil in Husky saws as they run hotter and faster and other oils are not designed to cope. I reckon he could be right as I've a friend that has got through two engines in two years on a new Husky 550 using Stihl oil.

SG

[Haironyourchest]

A local saw docter told me to only use Husky oil in Husky saws as they run hotter and faster and other oils are not designed to cope. I reckon he could be right as I've a friend that has got through two engines in two years on a new Husky 550 using Stihl oil.

SG

 

 

Or maybe I should seek help for my meme dependancy....

[Joe Newton]

I personally think that 40:1 makes sense as modern saws use less fuel, less fuel means less oil so if you pop more in, it will do no damage and may help the engine stay cooler, keep bearings in one piece and help stop seizure.

 

 

 

It is my personal opinion and is what I would recommend but what do I know:sneaky2:

 

 

Fair enough Steve, you know I defer to your knowledge on anything 2 Stroke.

 

As I understand it though, high quality synthetic 2 stroke oils already have that factor built in. I've read that RL for instance would be fine running on a much leaner mix.

 

Otherwise someone accidentally mixing at 51:1 would instantly cook their engine.

[R Mac]

I run 50:1 as that's what both the saw manufacturer and the oil manufacturer suggest.

 

I heard a theory regarding running e.g. 40:1 that I'll share, not entirely convinced TBH although I guess it sounds plausible, I didn't think too much about it as I wasn't changing from 50:1 any way.

 

The Theory, If you mix at 40:1 rather than 50:1 there's less petrol present in any given amount of metered fuel being delivered to the saw, the amount of metered air remains the same so at 40:1 the fuel has a greater percentage of oil and a smaller percentage of petrol. If the amount of air remains the same but you reduce the amount of petrol the mix is leaner, so the saws runs leaner at 40:1 than at 50:1.

 

Like I say, not my theory, not sure I'm convinced either way and in any case I'm running 50:1 as that's what the manufacturer suggests. I'd be interested in your take on the theory though Spud.