Two stroke fuel ratio

[Johnkv]

I'm sure this discussion is here somewhere I'd appreciate if someone could direct me to it or give me your thoughts on the following....  I run a 500i ,I usually run 50:1 with aspen 4 mixed with hp ultra. I've seen many teardowns on YouTube about lower crankcase bearing not being lubricated properly at 50:1. I understand this could be opening a huge can of worms here but would there be anything negative about running my 500i at 40:1 instead? Stihl will allways push 50:1 just looking for an honest opinion from you. Thanks. 

[Mick Dempsey]

Just run it as recommended by the manufacturers. 50.1 or an alkalyte fuel for two strokes.

[spudulike]

With a fully synthetic oil, 50:1 should be all you need for a well running machine. You could use 45:1 as a bit of safety and depending on how you make up your mix and the accuracy of that method but if you use too much, you may end up with too much carbon build up so 50:1 should work as the manufacturer intended or 45:1 if you want that little more safety.

A little note, for Gods sake don't say that 45:1 weakens the mixture as we have discussed this at length and don't want to hear it all again. I would rather go down the fish based responses again......perhaps I should have said for "Cods" sake!!!!

[Johnkv]

3 minutes ago, spudulike said:

With a fully synthetic oil, 50:1 should be all you need for a well running machine. You could use 45:1 as a bit of safety and depending on how you make up your mix and the accuracy of that method but if you use too much, you may end up with too much carbon build up so 50:1 should work as the manufacturer intended or 45:1 if you want that little more safety.

A little note, for Gods sake don't say that 45:1 weakens the mixture as we have discussed this at length and don't want to hear it all again. I would rather go down the fish based responses again......perhaps I should have said for "Cods" sake!!!!

What about a semi synthetic?

[pleasant]

14 minutes ago, Johnkv said:

What about a semi synthetic?

The same- if it's Stihl, then 50:1

[spudulike]

Yup, 50:1 is all you need but I tend to give it 45:1 as that is what I do and rarely run much for any prolonged use now.

My choice but 50:1 is all you need and don't use it after storing it for weeks, the fuel destroys the oil over time.

[Johnkv]

1 hour ago, spudulike said:

Yup, 50:1 is all you need but I tend to give it 45:1 as that is what I do and rarely run much for any prolonged use now.

My choice but 50:1 is all you need and don't use it after storing it for weeks, the fuel destroys the oil over time.

How much oil for a 5 litre can for 45:1?

[Johnkv]

Would it really matter that much between 45 and 40:1 ease of mind for a tiny bit more oil? 

[Mick Dempsey]

Why bother asking if you ignore the advice?

[Dan Maynard]

Wrong question really, you should ask whether it matters between 40 and 50. Yes it does. Don't over think it, thousands and thousands of hours of chainsaws have run 50:1 perfectly fine, that's why Stihl recommend it. I'd go with that rather than some bloke on YouTube.

 

(I run 50:1 myself)