71:1 Ratio Fuel Mix

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Trigger-Time

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71:1 Ratio, thats the Ratio for this pre mix.
Anyone here tried it?

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IMO......and just, IMO oil are soooo much better today and the Synthetic
oils are even better. I have hinted about running a saw at 60:1 or 70:1
to see how long it will last........again IMO, with the oil today I don't think
60:1 will hurt a thing with Synthetic.....am I going to gamble my $900
MS660 on 60:1......you can bet your a$$ I'm NOT! I just think the oils
will do better than they are telling us. IMO 50:1 is not the edge of the
mix, they have a safety margin, I would think.

Oregon, is saying that there oil will do a lot better than 50 to 1
 
IMO......and just, IMO oil are soooo much better today and the Synthetic
oils are even better. I have hinted about running a saw at 60:1 or 70:1
to see how long it will last........again IMO, with the oil today I don't think
60:1 will hurt a thing with Synthetic.....am I going to gamble my $900
MS660 on 60:1......you can bet your a$$ I'm NOT! I just think the oils
will do better than they are telling us. IMO 50:1 is not the edge of the
mix, they have a safety margin, I would think.

Oregon, is saying that there oil will do a lot better than 50 to 1

Ya know, If I could step back in time and tell someone running a saw in 1955 that I mix gas at 50:1, they'd laugh at me. It seems that over time we are mixing less and less oil. first 20:1, then 32:1, then 40 or 50:1, the trend continues.......
 
Ya know, If I could step back in time and tell someone running a saw in 1955 that I mix gas at 50:1, they'd laugh at me. It seems that over time we are mixing less and less oil. first 20:1, then 32:1, then 40 or 50:1, the trend continues.......

Very true.........I'm now going OT In 1989 I started changing
the oil in my pickup every 12,000 to 15,000 miles. Sold it to dad with
over 200,000 miles on it.....its just a farm truck now.....motor wise
I put one timing chain in it.....it still dose not smoke, will use 1/2 quart
of oil in 15,000 miles (Dino oil)........bought a new pickup in 2005, I'm
now using a blend, went 500 miles first oil change, now ever 15,000 miles
Oil is SOOOO much better IMO
 
I think another reason they are staying with the 50:1 on
the Synthetic, afraid people will mix dino oil to what ever ratio
the Synthetic oil called for.........but like the little Oregon 1 gallon
mix, dose not tell the ratio.......just mix pack with 1 gallon of gas.
I would say 95% of the people will not try to figure the ratio.
(and most don't know how)
 
I have a lot more 2 stroke motorcycle experience than I have of chain saw experience.
I have a different understanding than some of the posts here.
Some people speak of rich lean as the mix ratio of the oil and gas.
To me rich/ lean has to do with the jetting (air/fuel)
Going from 50:1 to 40:1 leans the motor out. Less gas more oil – they burn different.
More oil might provide extra lube but oil burns hotter ( may cause a problem).

My last big 2 stroke (bs 89x79) ran fine on amsoil synth at 88:1. I know the bottle said
100:1 but with that big of a piston I wanted a bit more oil to protect the cylinder from
Rocking forces. I spent some time to properly jet the carb in for this ratio.
Ring and piston looked fine at the end of the season but got changed anyway.

My motor with a 79 mm stroke , at 7500 rpm the piston speed in feet per min was 3887.
A 65cc chain saw turning 12000 rpm has a piston speed in feet per minute of about
3220 (assuming a stroke of 41 mm).
 
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