• Required reading for all forum users!!!

    Welcome!
    Register to access the full functionality of the GSResources forum. Until you register and activate your account you will not have full forum access, nor will you be able to post or reply to messages.

    A note to new registrants...
    All new forum registrations must be activated via email before you have full access to the forum.

    A Special Note about Email accounts!
    DO NOT SIGN UP USING hotmail, outlook, gmx, sbcglobal, att, bellsouth or email.com. They delete our forum signup emails.

    A note to old forum members...
    I receive numerous requests from people who can no longer log in because their accounts were deleted. As mentioned in the forum FAQ, user accounts are deleted if you haven't logged in for the past 6 months. If you can't log in, then create a new forum account. If you don't get an error message, then check your email account for an activation message. If you get a message stating that the email address is already in use, then your account still exists so follow the instructions in the forum FAQ for resetting your password.

    Have you forgotten your password or have a new email address? Then read the forum FAQ for details on how to reset it.

    Any email requests for "can't log in anymore" problems or "lost my password" problems will be deleted. Read the forum FAQ and follow the instructions there - that's what we have one for...

  • Returning Visitors

    If you are a returning visitor who never received your confirmation email, then odds are your email provider is blockinig emails from our server. The only thing that can be done to get around this is you will have to try creating another forum account using an email address from another domain.

    If you are a returning visitor to the forum and can't log in using your old forum name and password but used to be able to then chances are your account is deleted. Purges of the databases are done regularly. You will have to create a new forum account and you should be all set.

Around the world on a GS850G for a cause

  • Thread starter Thread starter shirazdrum
  • Start date Start date
I live in Uruguay, sorry my bad english.

I have always hear that gasoline in Brazil is not very good. what about to pour a bit of two stroke oil to a full tank or Diesel?
 
Ok i think the bike is ready. We took out the plastic spacers and replaced them with some aluminum ones .5mm shorter. I'm gonna take the bike out for a spin to see how the plugs look after a few miles. Stay tuned.
 
I'm meeting up with Eliseo in Uruguay on the 28th. The ferry from Buenos Aires turned out to be very expensive so i'm traveling overland to cross the river 250km north of Buenos Aires. Eliseo is a machinist and has a workshop in Montevideo so if anything goes wrong or the carbs need more adjustment, we can hack at it again in Uruguay. So one more day in Buenos Aires and will hit the road tomorrow morning for crossing the Plata river.
 
Hi RustyB
100LL has no ill effects on the bike that I know of, I ran my GS1000G on 100LL for about 4 years, and really could not tell the difference, that was seven or eight years ago, and when I pulled the bike appart for the rebuild, the moter was still running well.
No holed pistons or burnt valves.
I do find though that Avgas 100LL burns a lot drier than mogas, so a upper cylinder lube of sorts is a good idea, I just used to chuck in a half pint of engine oil with the fuel.
I never found it nessesary to re-jet or anything.
Being a poor flying student, throwing every last penny to flying, I used to take the fuel that they drained out of the fuel bowser every morning when they did the dips and checked for water.
Remember, my bike has done 375 000Km, of which, I would imagine around 60 000Km has been on Avgas.
I also live at 7500ft above sea level, where the air is a lot thinner, never had detonation.
Of course, always just do plug checks to be safe, I hope the nput helps in some way, but please don't take what I say as gospel or bet your motor on what I say. It is just mt experience.

Remember most of the general aviation aircraft and their engines were designed 30 or 40 years ago, and were built to run on 80/87 Avgas, 100LL has only been around 15 years or so.
All the Genreal aviation motors from Lycoming or Continental run 25 degrees static advance with no dynamic advance, as the rpm range is to narrow to justify dynamic advance, typically red lining at 2500rpm.
 
It was a million degrees outside so i'm leaving now for the test. Be back shortly.
 
Flyboy,

I didn't think there would be any bad effects from using 100LL, I just thought blending it with the B75 he is finding in Brazil, would make a nice down and dirty way of not having to re-jet His carbs.

thanks for the information on using engine oil as a top end lubricant. I never did find a definitive answer on that issue.

do you know how much, if any, ethanol is in 100LL?
 
The leader in fuel is Petrobras in Brazil, they have 3 different types of gasoline, the best and most expensive is the so-called "Podium" with high content of octane, but engine must be or exceeds 10:1 compression relation.
The second option is the gasoline called "Aditivada", which contains special additives for the domestic market with 20 to 25% of alcohol. This is not a good option for our old engines.
The last option is the "Comun" without additives, but I have no references to it.

In Uruguay I always use the gasoline called "super", but some years ago reduced the lead and this has bad fame on old engines for burned valves, therefore I add an additive of STP every full tank.
 
Last edited:
Dale, as far as I am aware, there is no ethanol in avgas at all, one of the reasons there are only three refineries in the world that produce the stuff.
One of the reasons that it is frowned upon to use mogas in aircraft is because the quality control is not as stringent as with avgas, so batches and supplies vary, whereas with avgas it is produced to very tight specs.
Also remember that the components certified for aircraft are still produced out of the same material, including rubber, that they were certified with 30 or 40 years ago, and those rubber hoses and components would not stand up to ethonol.
With the demise of avgas on the very near horizon, the manufactures are looking for alternative fuels, and testing with ethonol fuels has only just begun a few years ago, but it is purely testing, not in the commercial stuff.

Short answer, no, avgas does not contain any ethanol.

Typical formula
Alkylate~ 70 %
Isopentane~ 15 %
Toluene~ 15 %

Additives
Lead
Dyes
Scavenger
Antioxidant

In Brazil, All automotive pump gas, by federal law, must have between 20 and 25% ethanol added, even the premium blends...
 
Last edited:
I would go easy with the 100 Avgas, it burns hotter than car gas does. I used some 100LL that was free at the airport (overflow from Cessna tanks) when my first GS 550 was new, in about 1978. It ran great, but after about a half tank the spark plug's electrodes were melted down to little nubs, and the bike was misfiring very badly. This was with only a small percentage of 100LL in regular car gas. There were no other problems with carburetion or anything else, as the bike was nearly new, with new plugs and new gas the bike ran fine for another 100,000 miles.
If you can still find it, 80/87 should run better, I've used it in cars just fine, a lot of people do. I'm not sure about using it in the air cooled bike engines.

You should easily be able to jet for any reasonable amount of alcohol in car gas with a little trial and error.
 
Well sorry guys to keep you waiting. I went shopping :D. My windshield broke to pieces in Patagonia and after mending it with barbwires and such it was time for a new one. I found a new and very nice windshield for 90 bucks and jumped on it. (the pictures will be here soon)

The carb modification apparently worked. the plugs are in much better shape and more white stuff. But that's only 5 miles of testing. the definitive answer will come tomorrow night when i run for another 500km to Uruguay.

The gas in Argentina has a very little alcohol content if at all, so i can't blame the lean looking plugs on that. Eliseo is right about the Petrobras (The Brazilian chain), they do add alcohol to everything.

The alcohol is not really my problem as the alcohol flash point is around 55 where the gasoline is at -45 (the lower the more combustible). alcohol BTU per gallon is about 76,000 where the gasoline is at 114,000. So alcohol burns cooler if it does leave white residue that makes it look like that the mixture is lean.

That's why i worked my ass off to get the carbs with good gas to carburate a right mixture while i can see it rather than trying the same thing with ethanol gas.

So far it looks good, we'll know for sure tomorrow.

Chris
 
Chris, If you still have problems with the threading of the #3 plug, when you get access to a machine shop, have them put a helicoil in it. I have used this to cure the problem on a # of bikes over the years. John
 
Chris, you want LESS white. I believe the suggestion was to RAISE the needles to richen the mixture not lower them to lean it out more. It sounds like you lowered it.
 
Oh I thought he was already running the alcohol gas, that is just to come in the future... great :p

Plug 3 is loose threading in but doesnt cross and tightens up near the end. I cleaned it out best I could while it was apart... if he keeps it during maintenance stuff like this and only pulls it when its time to swap plugs he should be fine. My point was to make him aware of the issue to avoid making it worse.

pictures speak better than posts, if he put shims in I dont see how he could have adjusted it anyway but richening it... right?
 
Lots of cooks in the kitchen so don't want to confuse things further but the following are all reasonable methods to increase the richness of the mixture...

- Shim the needles by replacing the plastic washer on top of the clip with a washer stack roughly 1/2 as tall as the plastic spacer as installed from stock

- Open the pilot screws to as much as 3.5 turns from lightly seated

- Oil the air filter again. With a K&N you can spray oil right over the top of dirt on the filter and it won't hurt anything

- Move up one size on the main jets

Adding more oil on the filter is the easiest since the needles have already been shimmed.

Good luck and keep going...
 
Hi everybody, last news, while I was driving to work this morning, Chris call me on the phone for last minute instructions about the best route to the Uruguay border.
Im been with him last night after diner when I drop him in my mom?s house and we say good bye and wish him good luck, he is a great guy and we have a good time together.
Bye!

Adrian
 
Hi everybody, last news, while I was driving to work this morning, Chris call me on the phone for last minute instructions about the best route to the Uruguay border.
Im been with him last night after diner when I drop him in my mom?s house and we say good bye and wish him good luck, he is a great guy and we have a good time together.
Bye!

Adrian

Hola, Soy Eliseo y estoy esperando la llegada de Chris a Montevideo, Ayer le suger? que cruzara para Uruguay en el puente Fray Bentos . Tu tienes una idea de que ruta va a hacer?
 
Thanks for all your help Adrian, nothing against Argentina but I bet he is very excited to move on with the journey and see another country.
 
Back
Top