Running alcohol /methanol any experiance?

[nakomis0]

Well I'm toying with the idea of running Meth. From talking with a few guys and some research it sounds like its a matter of just changing a few jets.

But apparently a dyno with a sniffer cant read the fuel/air mix properly, and Keihen doesn't make the jets as large as I need to run so.. i need to drill the jets.

Has anyone done this, how hard was it to get the correct jets. We have access to a dyno, but it could be time consuming to do a run, then try and drill a jet and do it again.

So any info on your experiance would be good and maybe what jet sizes you ran.

The bike is a 400ex with the mods listed in my sig, the carb's a 39mm FCR

[MIKE400EX]

Large enough jets may not be the only problem. The internal passageways may need to be drilled out also (irreversible mod). Jetted correctly you might see a 15-20% increase in HP. Methanol consumpton will be about 2X gas, so don't wander too far from your truck. You'll probably need to put the stock - hotter plug back in. Be very careful about leaks and spills, you can't see it burn (raw gas usually burns black & sooty). It's a little more forgiving than gas when trying to get the jetting/mixture right. Check to make sure that any rubber, such as the fuel line and especially the carb float valve (needle) are not affected by the alcohol and become soft or swell. Havn't run any alky bikes/quads, just cars. Be careful and have fun.

Sorry for the rambling!

[aviator4]

MIKE400EX is close.. actually, all of the rubber seals and gaskets in your carb will have to be replaced - anything rubber that might come in contact with the fuel either in liquid or vapor form, Methanol will dissolve the quickly. Not to mention plastic/rubber intake manifold, fuel lines, bowl relief line etc...

a friend in our riding group changed over to methanol and didn't change out the seals. It ran fine the first ride out - second day it would run, but very lean we were all sitting around scratching our heads and THEN he told us about the methanol switch.. we coulda killed him... We took the bike home (this was a Raptor 660) and tore it apart, sure enough, one of the seals in the accelerator pump gave way and got sucked into the carb.

A few other things: methanol must be stored differently as it will absorb water. a "breathing" gas can won't work. An engine that runs on methanol should be flushed before any length of storage to prevent metal corosion, and the oil in the engine should be change MUCH more often to prevent alcohol accumulation. fuel stabilizers can't be used in methanol.

the good news is that it produces higher BTUs per pound of air. which means more POWER! :devil: and it vaporizes at a higher temperature, meaning it's somewhat safer to handle. Octane ratings for methanol fuels are generaly over 100.

On a side note here.. before we get too far, are you talking about Nitromethane, or methanol? - It just occured to me that we might be going in the wrong direction. I saw methanol in MIKE400EX'es reply and just kinda ran with it.

[nakomis0]

ya im talking meth,

and from my understanding if you flush with reg gas after each ride your seals and other rubber things should be ok.

its nice to hear the jettings forgiving. As far as drilling other passages that would suck.

I actualy just found a guy whos really into this stuff. He was saying he has 2 projects to do right now, but he said he would help me and get it running on it good, he said hes pretty cionfident he can do it, but most his work is on 2 strokes

[bradrenea]

I ran it in my 416 for a while. I tried drilling jets and it wasn't enough. Got them drilled out so much that the threads would snap off when screwing them in. Ended up running no main jet and filing the last inch or so of the needle down to about half the original diameter and it was about right.
I decided that the hassle of draining the fuel and running gas through it was not worth it to me. If you only rode on the weekends and had easy access to the meth it might be worth it. I had to drive forty miles one way to get the stuff and I have some trails and stuff at my house so I ride about every day. Draining the fuel and stuff got old fast.
I tried leaving it in there one afternoon. I got on it the next morning and fired it up and it would run and then die. Turned out it had drawn enough moisture over night that I had to drain the system anyway.
Really just depends how often you ride and if you can get the stuff easy enough.

[nakomis0]

Thats good info about the jets. I knoew I probably need about a 360-380 size main jet. and I know Keihen doesnt make jets anywhere near that size.

[Chef]

Why not call Sparks or FTZ or someone who has experience in running these bikes on alcohol? I know you can buy alcohol carbs from FTZ.

[bradrenea]

I just noticed in your sig that your running an FCR. I was using the stock Mikuni carb. If you go to CT Racing's website they have an Alcohol Tuning Tips page that I found to be helpful when setting mine up. I think it said on there to multiply your current jetting by 1.4 to get a baseline to start from when converting to alcohol. That wasn't even close with the stock carb for some reason but I am sure they would not have put it on there if it wasn't normally true. I had been given that figure by a couple other guys as well. There was also some other useful info. Its worth checking out.
Here is a link http://www.ctracing.com/alcohol.htm