Ethanol and Two-strokes...

T

tprnottp

New member
Question: Since the EPA has deemed it necessary to increase the Ethanol content of pump gasoline to 15%, what are you running in your two-stroke to compensate for the addition of ethanol???
In short, are you using a fuel additive along with your favorite premix lubricant, or have you switched to "pure" unleaded race gas???

Inquiring minds would like to know.

Thanks for the input,

TP
EC 300
 
I have two gas stations close by that sell 110 octane leaded gas at $5.79/gallon. I mix 2 gallons of it with 3 gallons of 93 octane unleaded.
 
I didn't think you could buy leaded gas at the pumps anywhere. I wish I could find that here.
 
In Oklahoma there are sill a few gas stations, usually one in every town, that sells fuel with no alcohol. I buy 91 octane and it works fine in both my 2 strokes.
 
I used to mix VP Red race gas 50/50 with pump premium, but it got too expensive and a hassle if I needed gas fast. The Starbrite Startron additive has worked great so far with pump premium. Biggest problem is the inconsistency and effects on jetting. Be careful in cold weather.
 
Startron additive is good, a 50/50 mix of 15% methanol pump gas with non- oxygenated (premium) gas is OK. Your octane rating should be high enough to prevent detonation. Actual methanol content is down to 7-8 %. You can also run a "castor based" oil. Maxima 927, Klotz Benol, there are many others as well. Castor based oils mix well with alcohol.
 
Most synthetics do as well, but the ethanol absorbs moisture from the air and causes some components to separate. Its worse with ester based synthetics like Redline. Castor based oils are very dirty.
 
Thanx for the link Clay.....I verified the info that was stated for one particular station near my location and now I know where I'll be purchasing ethanol-free fuel.
:cool:
 
mcnut said:
I have two gas stations close by that sell 110 octane leaded gas at $5.79/gallon. I mix 2 gallons of it with 3 gallons of 93 octane unleaded.
Click to expand...
Does the 93 have ethanol ? I don't want any ethanol.
The compression is @ 165psi. in my 300. I got some Sunoco 110 and I'm gonna try it straight. If that doesn't go well, I'll try 100LL from the airport. If it doesn't like that, I guess I'll stick to pump gas with Startron. :(

I've heard that the chances of 15% coming to market are slim. If it does, only new cars that are designed for it will use it. Stations will have to offer both 10% and 15% for many years. I'm thinking they're gonna put up a pretty big fight against that.
 
I would stongly agree with two of GMP's points that

1) the ethanol blend is very inconsistant, don't count on it having the same ratio of alcohol to gasoline as the sign on the pump says

and

2) the alcohol molecules in ethanol actually attract water very easily.

If you have to use ethanol consider using an additive and keep your fuel fresh as it goes flat very quickly. Of course the biggest problem with ethanol is you have to watch your jetting as ethanol burns leaner.
 
Brian VT said:
Does the 93 have ethanol ? I don't want any ethanol.
The compression is @ 165psi. in my 300. I got some Sunoco 110 and I'm gonna try it straight. If that doesn't go well, I'll try 100LL from the airport. If it doesn't like that, I guess I'll stick to pump gas with Startron. :(

I've heard that the chances of 15% coming to market are slim. If it does, only new cars that are designed for it will use it. Stations will have to offer both 10% and 15% for many years. I'm thinking they're gonna put up a pretty big fight against that.
Click to expand...

It is my understanding that the station selling the fuel must have a sign saying that the fuel contains alcohol. In OK the sign will say this fuel may contain up to 10% alcohol so it may be 10% or 1% who knows. Here the 100% gasoline stations charge about 10 cents more a gallon for "pure" fuel. As far as octane goes you only need a high enough octane rating to prevent detonation. There is no benefit to more octane if you don't need it. Different fuels can have more or less BTUs per volume the important thing is to get a consistent supplier that has fuel with high enough octane for your engine get it jetted for that fuel and stick with it.
 
GMP said:
Most synthetics do as well, but the ethanol absorbs moisture from the air and causes some components to separate. Its worse with ester based synthetics like Redline. Castor based oils are very dirty.
Click to expand...

Redline has always separated in the 2 stroke oil. I used to run is with VP c112 when I road raced a Honda RS250 in the mid 90's. When I opended the cases and would pull the crank, it was always bathed in oil like it should be. I would never let the gas set in the tank for more than a day. Other wise I would drain it back into the my 5-gallon jug and screw the top on. I would shake it real good before putting back into the tank to run.

I wasn't dealing with ethonal then, but I think the same thing applies to keep the water out and the oil mixed if you choose to use it. Personally I use Bel-Ray MC-1 because it doesn't separate.
 
lankydoug said:
There is no benefit to more octane if you don't need it.
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...and, I'm told, too high of an octane rating can result in hard starting and a (slight) loss of power and increased unburnt exhaust.
That's why I'm concerned that my bike might not like the 110. We'll see.
I don't mind paying more to stay away from ethanol.
 
Brian VT said:
...and, I'm told, too high of an octane rating can result in hard starting and a (slight) loss of power and increased unburnt exhaust.
That's why I'm concerned that my bike might not like the 110. We'll see.
I don't mind paying more to stay away from ethanol.
Click to expand...

High octane burns slower and usually requires more spark advance, higher compression or a leaner mixture or some combination of all of these.

If you don't have detonation problems and your bike runs good on 91 octane the way it's jetted why pay more per gallon? However if you have modified the engine to achieve higher cylinder pressures you may have no choice but to run 100 or 110 octane and you will realize the benefits when you do.
 
Stay away from AV gas unless you want to go thru trial and error re-jetting. Av gas octane isn't the same as pump gas octane. Check out a thread and posts' started on 2-26-08 under Fuel and intake/ 2 stroke. One of our members, Kim, asked some of the same questions. The short answer is pump gas is made for Chevies and Toyotas. It will work in 4 cycle bikes, but somewhere you need to add octane boost, startron stabilizer or mix with race fuel to work well in a 2 stroke( and not a bad idea in 4 strokes either).
 
Brian VT said:
To avoid ethanol.
The only options I have are Sunoco 110 or 100LL (AVgas).
Click to expand...

I agree that AV gas can be flakey when the weather/air density altitude changes and I would avoid any fuel with alcohol. It seems to me that Sonoco 110 is your best choice but I would not just try it and if it doesn't run right quit on it. It is different in octane and BTU than what you have been using so you will most likely have to re-jet and tune a little.
 
Actually Brian the 300 should not have a problem with detonation. The 250s run a bit more compression, mine is up around 190-195 PSI, and fine on pump gas. Ron at RBD told me 200 PSI is about tops for pump fuel. We have had this crap here in NJ for years now, nothing new. I agree on the AV gas, its a different animal with a completely different additive package, not like race gas. I've used it many years ago during the gas shortage of the late '70s as my dad worked at an airport, even in my '78 Fiat Spyder that was one of the last cars that ran on leaded gas. OK results but never tuned the jetting of the bike. If you can get the 110 I'd just do a mix with pump 93.

I'll do the race gas mix in the early spring enduros. Cold, sand, and winter fuel with ethanol can spell trouble if your not rich enough. The race gas takes some of the ethanol out of the equation. Otherwise I don't bother anymore.
 
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