Mixing fuel

okbeast · Aug 5, 2008

Well working a 7-5 job makes it pretty difficult to go anywhere to get race fuel during the week and be able to ride on teh weekends. I have found a few places that carry methanol and was wondering what the opinions of the builders is on this. There was a post on HQ awhile back but I don't think anyone ever had substantial yes/no evidence so I wanted to bring it up again. I've found a local place that also sells 118 octane for around the same price as 110 so I figured I could just mix the 118 and some 87 and be set, but figured i'd throw the question out there.

What I'm really looking for is a definate test proven answer, but opinions "yeah i've done it, and it works" answers are cool.

I have mixed both race fuel and pump gas and had good results, and also ahve a guy in our group that mixes 87 and methanol on a high compression bike and it runs fine.

Also what would be a result of mixing unleaded and leaded fuels, anything?

Bansh-eman · Aug 5, 2008

read through this.. there is everything you could need to know about race fuel right here

http://www.whitfieldoil.com/www/docs/171/vp-racing-fuel-

06banshee · Aug 6, 2008

I mixed VP c-12 with 93 octane pump gas and bike ran good and I ragged that old ported motor.Then I found av gas cheaper and 100octane so I just used that but yes Mixing worked good also just was way to far and to expensive.

dajogejr · Aug 6, 2008

QUOTE (bansh-eman @ Aug 5 2008, 04:03 PM) index.php?act=findpost&pid=7508read through this.. there is everything you could need to know about race fuel right here

http://www.whitfieldoil.com/www/docs/171/vp-racing-fuel-

I'm not going to give that site too much credit, based on some of these answers right here:

http://www.whitfieldoil.com/www/docs/171.2...cing-fuel-.html

For example...bigger bore needs more octane? So, someone that bores from .020 to .030 over should go put some race fuel in?
I'm not saying the statements are false...I'm saying they should be written and clarified a little better than the general/broad way they are written now....

badassbanshee479 · Aug 6, 2008

careful what ya read on the internet! alot of it is just peoples opinions!!

okbeast · Aug 6, 2008

QUOTE (badassbanshee479 @ Aug 6 2008, 06:24 AM) index.php?act=findpost&pid=7572careful what ya read on the internet! alot of it is just peoples opinions!!

Hence why I asked for real data if there is some...?

okbeast · Aug 7, 2008

Anyone else got opinions on this, goin to get a load of fuel tonight...

travis fulton · Aug 7, 2008

what cyl pressure u at now, blending fuels is ok if u know what u are doin! as high octane fuels are blended chemicles. if i know a few specifics i can help

okbeast · Aug 7, 2008

Cranking compression was 165 when I put it together. With cut 18cc domes and the squish I had I was thinking it would be higher, and it may have gone up some since I have ran it. I'm just being precautious running race fuel and will probably just pick up some 104 tonight.

Portking · Aug 10, 2008

I was told from Sunoco to have full mixture of two fuel the specifique gravity need to be the same. The Only one that completle mixes has methanol in it.

If this is true or the tail of a salesmen i dont know.

One thing i do know is that i've never mixed fuel you buy the right stuff for you motor. Why contaminated with pump gaz.

3 years cheetha 535 running on pure VP C12 never hade a prob.

One guys opinion not a fact. I would like to see some proof of this to.

koolguyson · Aug 12, 2008

QUOTE (okbeast @ Aug 5 2008, 08:47 AM) index.php?act=findpost&pid=7481Well working a 7-5 job makes it pretty difficult to go anywhere to get race fuel during the week and be able to ride on teh weekends. I have found a few places that carry methanol and was wondering what the opinions of the builders is on this. There was a post on HQ awhile back but I don't think anyone ever had substantial yes/no evidence so I wanted to bring it up again. I've found a local place that also sells 118 octane for around the same price as 110 so I figured I could just mix the 118 and some 87 and be set, but figured i'd throw the question out there.

What I'm really looking for is a definate test proven answer, but opinions "yeah i've done it, and it works" answers are cool.

I have mixed both race fuel and pump gas and had good results, and also ahve a guy in our group that mixes 87 and methanol on a high compression bike and it runs fine.

Also what would be a result of mixing unleaded and leaded fuels, anything?

You would need to tell us what you are running if you want an accurate answer on mixing fuel. Mainly what kind of compression and timing that you are running.

millertime · Jan 18, 2009

i downloaded a octane mix calculator.. i can't rember where i found it.. but if you google it you will find a bunch of them

njbanshee · Feb 7, 2009

Don't be cheap, buy the good stuff. You might save a little here and there but you will pay out the [censored] if [censored] goes wrong.

87sheerips · Apr 7, 2009

at 165psi, Ive ran 93 octane with no problems for years. Hell, my buddy was at 175 psi running 93 with no problems. I'm not saying that's the right thing to do at 175psi, but he had no issues. Ive talked him into running 110 these days, but at 165 Id just run some 93!

gloryforixseal · Jun 18, 2009

I too have also done this with one addition. I glued one fuel holder clip on the air filter to hold the fuel line above the brake rods. This keeps them from moveing around and getting rubbed on or worst cut.

bubba297 · Jun 18, 2009

IMO it's having a good oil that blends well. I have mixed 110 and 93 in our rider bikes for a very long time, and they would rattle the plugs out on straight pump gas. I like the addition of race fuel also for the added lead. Lead is a natural lubricant and sure cant hurt a 2-smoke. When premium gas was over 4.25 a gallon race fuel at $7.50 a gallon wasnt that bad LOL.

Radar · Jun 18, 2009

I've mixed 110 and pump gas but I was told by a builder to mix 110 with 87 octane to make sure it didnt have ethanol and never had a problem on a 170 psi Bike mixed 50/50.
I thought Methanol didnt mix right with Gasoline??? Otherwise maybe we could make our own cheap 50/50 " M 50 " fuel. Thought about it but was told Meth wont mix.

bubba297 · Jun 18, 2009

Todd, I have leaned down gas bikes with a little methanol before. There again I believe the oil has everything to do with that aspect. You just need to be as exact as possible.

For every 10% methanol added, an adjustment of 12.5% jetting to initially compensate. Of course for every altitude, humidity, temp, etc that value will be a little different. And also that will only hold up to a certain percentage.

Radar · Jun 20, 2009

That's why I was wanting to be able to do it was leaning down an efi bike just a tad with maybe a pint or qt of meth. Maybe we'll do it if needed. It would be cool to be able to jet a gas bike for say 25% meth and not have detonation and cheap gas mix or lean down a gas bike a little.

Buttermilk · Jul 9, 2009

Interesting topic.

I have some thoughts on blending fuels, but am by no means am an expert.

I did a test, uncontrolled, but a test non-the-less, on blending methanol and race gas. Simply blended a 50/50 mixture, volumetrically, of TT111 and methanol and let it set for 3 days. Looked like it blended just fine to my naked eye. I have not ran it in a quad yet.

Also, one reason the "experts" say that larger bores need more octane is simply that the larger bores take longer for the flame front to get to the outer edge of the bore, increasing the chances of detonation. Now, by larger, they really mean larger, not necessarily a simple over bore, but more along the lines of say going from a 66mm bore to say a 85mm bore, for example.

If you can get your combustion chamber to be very efficient and combust/burn the fuel at a very rapid rate, then you can run less timing, and have more compression with less octane requirements simply because the fuel will burn/combust before it has time to detonate. This is one reason you see increased compression ratios on modern street bikes, dirt bikes as well as atv's.

I've ran blended fuels before with no problems. I normally did this to decrease my cost of fuel.

One setup I had I could run 101 octane just fine. Motor had 210 psi cold cranking compression. Changed to a slightly different setup (different pipes, etc.) and still had 209 psi, but that motor detonated bad on 101 octane. Pistons didn't live through one race. Rebuilt with same setup and switched to 110 octane, and the motor ran for 3 years before I tore it down to do a different build.

I am considering running a 50/50 blend of gas/methonal on one of my quads, but may choose to run E85 instead (it's readily available from two locations near me).

Regards,

Rog