Ethanol Is Bad For 2-strokes!!!

[Honda 250r 001]

This is what happens when you try to run 190 compression and a really ****ty low octane fuel.
I was flat tracking with my friend messing around in about 4th WFO, i was doin great until about the 5th lap when i took a break and the ol R wouldnt idle. I immediatly shut it off thinking it was about to seize. Waited 5 minutes and still wouldnt start back up. We pull started it and it made a scary noise when we got it started. So i pulled it home and this is what i found.

[1promodfan]

We've been trying to tell you about running pump gas with 190lb. of compression. Race gas cost more now, but in the long run you'll pay more by trying to be cheap.:blah:

[Honda 250r 001]

Originally posted by 1promodfan
We've been trying to tell you about running pump gas with 190lb. of compression. Race gas cost more now, but in the long run you'll pay more by trying to be cheap.:blah:

haha, yep im not blamin anyone but myself. I would have been good if i would have stayed with the premium 91 or 93. My plan is to drop compression a little, around 5-10 psi and run 91.

[IcutMetl]

It's been my understanding that 185+ is a real gray area for even premium pump gas. Mine tested out at 195-200 and I've had good luck so far with a 50/50 mix with 93 and 110.

[rrguy]

So why would you post ethanol is bad?

did you drink some? lol

[Honda 250r 001]

Originally posted by rrguy
So why would you post ethanol is bad?

did you drink some? lol

ethanol caused this. I ran premium 91 or 93 all the time until i ran this 10 percent ethanol and then she blew.

[rrguy]

there can be several contributing factors.

So what octane was the gas you ran with 10% evil ethanol?

Has the temp recently dropped?

Does the machine normal get run Wot like that?

Most people know when jetting or changing fuel on a 2 stroke if it runs way better, you best to see how lean it is if you want it to run long.

A quick thing about ethanol or alcohol

Alcohol is oxygenated so it will burn leaner. it also burns cleaner. Ethanol its self has an octane over 100, burns slower giving you more power if setup correctly. If you try to run any form of oxygenated fuel you need to compensate.

Also during colder weather most 2 stroke oil & alky can separate so you need to run a Castor oil.

I am not saying ethanol is the best fuel for 2 strokes, but when running any alcohol or different fuel you need to be aware of it characteristics. It seems to me you are using the logic along the lines people get shot, guns are bad?

[morse250r]

ya that ^

[86 Quad R]

was the octane rating the same for the ethanol blend that you were using at the time of the engine damage?

[Honda 250r 001]

Originally posted by 86 Quad R
was the octane rating the same for the ethanol blend that you were using at the time of the engine damage?

the ethanol at our pump is 87 or 89. and the premium i was running was 91 or 93 i canr remember. But i never had a problem with any seizing until dumping the ethanol in it. the ethanol at our pump is 10 percent concentrated.

[Ruf Racing]

Originally posted by Honda 250r 001
the ethanol at our pump is 87 or 89. and the premium i was running was 91 or 93 i canr remember. But i never had a problem with any seizing until dumping the ethanol in it. the ethanol at our pump is 10 percent concentrated.

I believe it was a coincident. Ethanol had no bearing on the outcome. Your compression requires more octane then the 93 you were providing.

[Honda 250r 001]

Originally posted by Ruf Racing
I believe it was a coincident. Ethanol had no bearing on the outcome. Your compression requires more octane then the 93 you were providing.

what ever the cause, i will never run ethanol in a 2-stroke again.

[86 Quad R]

good luck with that. i dont believe there is a station left that doesnt contain ethanol. at least in these parts there isnt.

[Honda 250r 001]

the premium here does not have ethanol in the fuel. Im planning on running that from now on, lowring the comp to 185 and calling it good.

[rustyATV]

I didn't see any signs of detonation pitting that you would get from too low of an octane rating, so I don't think that was the culprit.

Air/Fuel ratio for gasoline is about 14.7:1

Air/Fuel ratio for alchohol is about 9:1 (if I remember)

Without getting into specific gravities and what not, from that you can guess that you'll run way lean if you don't change the jetting.

[C-LEIGH RACING]

Didnt you just put that top end back on ??.

Any time you have gas with alky mixxed with it, the alky will cause the engine to run leaner, so in turn you need to put in larger jets.
That ethanol gas can be ran in a 2 stroke, you just need to understand what the alky is doing inside the engine. Things like, the 2 stroke oil your using, is it mixing with the ethanol, need to be sure of that.

What would have been nice, if you had changed those jets & did some testing just to make sure it was rich enough while running that mix.

Pump gas & just running without testing it ='s a messed up engine for sure, mater of fact, even a temp change the jets need to be changed.
A high compression engine can be ran on pump gas, but you would need to have the jets so big & it would be so rich trying to keep the piston cool that it would rob quite a bit of HP in doing so.

Remember this, a 2 stroke engine, it makes no difference who it was built the engine or quality it even if it was Sparks or CT Racing, it will run no better or last no longer than the knowlage that who ever is tunning on that carb has.

Carb man will make or break it.
Neil

[factoryX]

there are several states that have banned ethanol because of motor problems caused by ethanol. Hell, the shell stations here in bend oregon sell ethanol free premium, and my bikes have never ran better.:eek2:
Oh, now that global warming is fake we should see it go away.

[rustyATV]

I tell people all the time; you build the engine for the fuel, you don't build the fuel for the engine.

Goes way over everyone's heads.

[woodsracer144]

Originally posted by Honda 250r 001
ethanol caused this. I ran premium 91 or 93 all the time until i ran this 10 percent ethanol and then she blew.

dont mean to be mean but you using it wrong!

i would like to know what kind of set up and jetting you have in your carb... i know people that run this isn banshees and get more Hp then 110 race gas... its all in your set up... could you post a better pic as well? thanks

[woodsracer144]

Originally posted by C-LEIGH RACING
Remember this, a 2 stroke engine, it makes no difference who it was built the engine or quality it even if it was Sparks or CT Racing, it will run no better or last no longer than the knowlage that who ever is tunning on that carb has.

Carb man will make or break it.
Neil

Neil, you couldnt have said it anybetter! i've rode stock motors that pulled harder then a 310 because the carb was so far off on the 310! it was annoying as hell to ride the 310...