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Questions about race gas


dburnexx

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So. While we are on this topic, I am running a 4mill crank. 110 rods. 68mm pistons with 19cc domes in a cool head and a cub cylinder. What octane rating should I be running? And what fuel/oil ratio would be recommended?

what is your compression and what kind of porting? according to the chart i posted earlier in this thread those domes on a stock engine, stock porting would yield about 183 psi at sea level. Increased stroke would raise compression. heavy porting could lower cranking compression giving you a false idea of octane needed. you will definitely need more then pump fuel unless your at a very high altitude.

 

Edit: realized it wasn't this thread I posted the dome to elevation chart so here it is. Untitled_zps10095a26.png

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24:1 gas-to-oil ratio in tx? You could take your head off and scoop oil out of the cylinders with your hand! haha

 

Seriously though, 32:1 or 40:1 will be just fine. I live in east central Oklahoma and I run 40:1 because of the summer heat and humidity. 40:1 is plenty in my part of the world.

 

Before switching to AV gas or race fuel I would suggest asking who ever built your motor and see what his opinion is? If your bike is running fine now, I wouldn't mess with switching fuel. You will probably only gain 2-3hp max I would assume and I don't think your butt dyno will be able to tell the differene. On another note, the smell of mixed race fuel gives me a stiffy!

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I'm in Wichita Falls tx. I believe 1000 feet or so above sea level. So would 110 octane be rite for me? And what kind of fuel oil ratio to mix at? Manual says 24:1. I was mixing 32:1.

u didnt say what your compression was at.
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Well the compression is at nothing rite now. If you look at the thread, "broken piston on right bank". That is my thread. That's the situation with my shee rite now. Had people telling me that the 93 octane fuel wasn't high enough in octane rating. So I was getting detonation. And in turn, that blew up my skirt. And I bought the bone used. I don't know who built the engine.

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didnt even look at that post or thread, thought you were just posting in reply to the topic of race gas. I'd be running 110 personally possibly a 50/50 mix but I would have checked my compression when purchasing it myself and would have had a good idea of what I needed. 19cc domes is a dead giveaway pump fuel is most likely too low octane. Also what do your domes look like now? Are they all pitted from detonation?

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Yes. They were pitted. This is my first shee. So I had no idea the following these bikes had lol. I'm going to rebuild it. Then slap a for sale sign on it. I've got 6 bikes in the garage. I can't afford to maintain them all the way they need to be. So I gotta thin the herd. Getting an 07 kx250f done too. And that will be for sale too.

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So. While we are on this topic, I am running a 4mill crank. 110 rods. 68mm pistons with 19cc domes in a cool head and a cub cylinder. What octane rating should I be running? And what fuel/oil ratio would be recommended?

 

 

Well the compression is at nothing rite now. If you look at the thread, "broken piston on right bank". That is my thread. That's the situation with my shee rite now. Had people telling me that the 93 octane fuel wasn't high enough in octane rating. So I was getting detonation. And in turn, that blew up my skirt. And I bought the bone used. I don't know who built the engine.

 

uhh the title of this thread clearly says "Questions about race gas" which is why we were answering your question......about using race gas.

 

We wouldn't know about your broke piston unless we were reading the thread titled, "broken piston on right bank" now would we??

 

So back on topic about RACE GAS it's pretty simple. If your compression is around 160-165 you may want to think about switching to a higher octane fuel to avoid deto.

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uhh the title of this thread clearly says "Questions about race gas" which is why we were answering your question......about using race gas.

 

We wouldn't know about your broke piston unless we were reading the thread titled, "broken piston on right bank" now would we??

 

So back on topic about RACE GAS it's pretty simple. If your compression is around 160-165 you may want to think about switching to a higher octane fuel to avoid deto.

If you would have read a few lines of THIS thread. He was asking ME what my compression was. I told him 0 because of a blown engine. And that he should read that to see what my situation is. So instead of you jumpin down people's throats, try reading a little bit before you start yelling at people.

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no, YOU need to re-read your own posts and the order the comments where posted in apparently.

 

 

So. While we are on this topic, I am running a 4mill crank. 110 rods. 68mm pistons with 19cc domes in a cool head and a cub cylinder. What octane rating should I be running? And what fuel/oil ratio would be recommended?

 

so i posted

 

what is your compression and what kind of porting? according to the chart i posted earlier in this thread those domes on a stock engine, stock porting would yield about 183 psi at sea level. Increased stroke would raise compression. heavy porting could lower cranking compression giving you a false idea of octane needed. you will definitely need more then pump fuel unless your at a very high altitude.
 

 

 

you replied yet again with no mention of a compression or saying your engine had 0 compression.

 

 

I'm in Wichita Falls tx. I believe 1000 feet or so above sea level. So would 110 octane be rite for me? And what kind of fuel oil ratio to mix at? Manual says 24:1. I was mixing 32:1.

 

i again asked you what your compression was cause you never stated it STILL!

 

u didnt say what your compression was at.

 

still at this point no mention of a broken engine. even after asked 2 times what your compression was but you come back with a smart ass remark like the this.

 

Well the compression is at nothing rite now. If you look at the thread, "broken piston on right bank". That is my thread. That's the situation with my shee rite now. Had people telling me that the 93 octane fuel wasn't high enough in octane rating. So I was getting detonation. And in turn, that blew up my skirt. And I bought the bone used. I don't know who built the engine.

 

So who should have read what? With comprehension skills like your own its no surprise as to why you have a blown engine. We are not mind readers but its obvious that even if we could read minds there is nothing in yours to read. You sir are an idiot.  Good day sir

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LOUD NOISES !!!!!!!!!!!!!!!!!!!!!!!!!

 

 

 

Edited by WINDYCITYJOHN400
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LOL

 

Now I think you're having trouble keeping track of who you're bitchin at. LMAO

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lmao Windy I know who you are referring to. Touche'

 

 

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