2 cycle gas mix ratio

[waterpirate]

When I went full tilt husquavarna I only run the pre mix stabilized fuel. Since the switch I never looked back. It is pricey, but if not using it as a pro It is well worth it IMHO. No fouling, no mixing, no worries about over winter storage, cuts down on pm, and they always start and run well. Chainsaw and weed whacker.
Eric

 

[idahovette]

@waterpirate ,haven't been at it too long, just started with my Bride's little rototiller and my old McCullough 610....Works good so far

 

[Grit dog]

You don't need a motorcycle license here in MT, but I think I do have to register it, which is a bummer, since the older lady who gave it to me has since moved, and I have neither a title nor a bill of sale. That could be interesting, so right now, I'm just hoping I don't get pulled over. I'll post a pic or two here when I think about it.

Aaron

MT requires motorcycle licenses. But not scooters I believe which is typical about everywhere.
Yes short story is oil is 300% better now than in 1978. As evidenced by 2-3k oil changes are now 6-10k oil changes.
I’m sure even cheap off brand 2cycle is a lot better. And good stuff, I never mix richer than 40-50:1. Been using Amsoil Saber as kind of a test for a few years now. A quart goes a long ways in the weed whipper and leaf blower. Even with 5 acres in the PNW jungle.
Saber and Outboard Pro claim 100:1 ratio is safe.
I’m up to around 70:1 and haven’t stuck a piston yet. I run about 8-10gal of premix through the small engines a year.
My sleds run happy at a calculated 50ish:1. Always check them at first as it was a problem sometimes being lean on oil setting from the factory for emissions requirements.

 

[Grit dog]

And then the “rich” guys show up to the party!!
Canned 2 stroke gas? I suppose if you only use a quart or 3 a year… but holy hell they’re proud of that stuff.
I do agree on the shelf life and stability being far superior to even pure gas from the pump though.
But I’d need a second job to use that stuff….
Plus I’m generally just morally opposed to paying 5-10x what something is actually worth when the effort to save $10 or $10000 is minimal.
Though I do the same thing but I just go get 100LL 5-10gal at a time from (any) airstrip. Same thing but better because …lead. It’s good for a couple years minimum. Saves draining and running dry all the small engines. Also makes generators start reliably after sitting for however long. The emergency powers out gennys get reg gas if I’m hogging on them during a power outage but drain that out in the spring and drop a gal or so of Av gas in em, = starts first pull when it’s raining sideways at 1am and the lights go out.

 

[78C10BigTen]

Any body run the quart "canned " 40:1 or 50:1 gas in chain saws or other small mix engines?

I use the off the shelf premix fuel oil in my husq rancher 455 chain saw cus im to lazy to make mix lol

 

[idahovette]

OK @Grit dog that works for you.....BUT I'm old and I don't have the time or inclination to waste it, mixing and cleaning up the mess for what little of this stuff that I use. This exactly @78C10BigTen

 

[Grit dog]

OK @Grit dog that works for you.....BUT I'm old and I don't have the time or inclination to waste it, mixing and cleaning up the mess for what little of this stuff that I use. This exactly @78C10BigTen

I should quote this for Funny Stuff from the Internet thread!
I acknowledged the small quantity justification. I get it.
But you being a lifelong mechanic AND retired, your busy schedule and it being a “mess” is absolutely hilarious!
fWIW the shelf life in those cans is seriously impressive. I got an unopened can of Craftsman premix with a cabinet and the fluids in it from an estate sale. (Best deal ever, I’ve probably used $200 worth of stuff from that $30 purchase. Have t bought black Rustoleum spray paint in 5 years!!). Also got some cool unopened vintage oils and stuff.
Thst rusty can of premix had to be OLD. At least 5 years as the old lady said that was how long ago her husband had passed away. Opened it up, smelled good and worked just fine in the leaf blower.

 

[Ricko1966]

Well here's another for what it's worth,oil displaces gasoline so a 50:1 mix contains more fuel than a 25:1 mix,so you may run a little rich. Whether or not it's enough richer to cause any problem as to plug life or washing the oil of the cylinder wall,IDK I'd be more tempted to run 32:1 if I wasn't going to run what was recommended. But really I think I'd just run what was recommended.

 

[Grit dog]

Well here's another for what it's worth,oil displaces gasoline so a 50:1 mix contains more fuel than a 25:1 mix,so you may run a little rich. Whether or not it's enough richer to cause any problem as to plug life or washing the oil of the cylinder wall,IDK I'd be more tempted to run 32:1 if I wasn't going to run what was recommended. But really I think I'd just run what was recommended.

Definitely splitting hairs there. There’s more variable in moderate temperature and altitude changes. That same motor is running about 3% richer on fuel in KC than sea level and that’s only 1000’ altitude and there would be zero difference in jetting recommendation below say 3000’.
And 25:1 is pig rich on oil in any 2 stroke I could ever imagine.
Before oil injection we used to run sleds at 30-40:1

You’ll never seize it due to lubrication but she’ll be a slobbery mess on the outbound end!
If one just wants to be ultra safe and doesn’t mind the smoke, mess (not the mess making a can of premix…lol), extra oil use and greater propensity for oil fouled plugs, have at it. But just like us humans, 50:1 is the new 32:1….lol.

 

[Memaloose]

I use the canned premix 2 stroke fuel now as I only have one weed eater anymore but it ain't cheep.

 

[AaronW]

wow, look like we ended up with quite a discussion here. I hadn't thought of getting some gas at the airport. I live within spitting distance of our small one here locally. I'd be interested to see if that makes the mpg on the moped even better.

Aaron

 

[Grit dog]

wow, look like we ended up with quite a discussion here. I hadn't thought of getting some gas at the airport. I live within spitting distance of our small one here locally. I'd be interested to see if that makes the mpg on the moped even better.

Aaron

Doubt it will. It may even be a bit too high on octane assuming the scooter is designed to run on low test. And altitude further reduces octane requirements.
But it’s not “that” high (and we all know 110 will run fine in any old motor just leaving some performance on the table doing it but it will sure run cooler and smell good). 100LL burns roughly about like 95 octane R+M/2 although there is more to the correlation.
I use it only in select applications where I feel it makes sense for a reason (except last month when I mistakenly dumped 5 gal of it in the mower and it was windy so I didn’t smell it. But saw blue in the clear filler when it was getting full).
My 450 snobike. Loves the stuff. Lead is nice on them solid lifters and cam. And it wants 92/93 at a minimum anyways and it get run wfo high load for long periods so the slower burn helps with heat.
Everything else is just for convenience of not having to keep track of not having fuel go bad in seldom used stuff. Like here soon, I’d typically go put some in one tank of the squares and the old Jeep since they don’t get driven much or at all due to the seasons or no one around to drive them.

 

[WFO]

I run Maxima Formula K2 100% Synthetic at 32:1 with non ethanol gas in my Motocross bikes. Never a fouling problem. Plus, I'd much rather foul a plug than scorch a cylinder by going too lean on the oil.

Been running the same premix in my 2 stroke Lawnboy lawnmower.
It started up on the first pull this Spring, on its 36th season.
I mow about 1 1/2 of my 3 1/2 acres. Have a heifer that mows the rest.

 

[Trucksareforwork]

Yeah… I always just assumed that 50:1 is about manufacturers wanting to make environmental claims and not about engine health.

Kinda like zero weight crankcase oils these days.

 

[Grit dog]

Yeah… I always just assumed that 50:1 is about manufacturers wanting to make environmental claims and not about engine health.

Kinda like zero weight crankcase oils these days.

On the latter, yes in some cases, necessity in others. No one recommends a 0W0. And every engine is happy with 0weight at extreme low temps. But 0W20 or 30 is akin to the forever 10W30 that was a recommendation for decades in most vehicles.
Also nothing wrong with being safe on 2smoke ratios and I believe the newer 2s oils burn cleaner so reduced fouling even at “old” mix ratios.
But the fact remains, “old” mix ratios are largely a product of the lubrication properties of old oils.
Adding an extra factor of safety with richer oil ratio than necessary is just that. It’s a factor of safety for when things don’t go right, like fuel mixture leans out too much and also decreases the total volume of oil on every turn of the engine.