Bad Gas

[Cracker Jack]

Last week I put gas in my IS and since I record all gas purchases, I noticed that the last time I bought gas was late November. that was almost 7 months ago!

Mine stays on a tender so I don't worry about keeping the battery charged. Since November, the bike has been ridden maybe three or four times but not enough to need  gas.

The bike started and ran fine as if it had been ridden the day before.

Would somebody who KNOWS tell me what are the symptoms/characteristics of bad gas. Did I have bad gas and did I do any damage to the bike by running it. I just filled it up and everything seems fine.

If I can be a little picky, I don't need any uninformed opinions from people who may not know any more than I do. In that case, I'll just form my own opinion. Only informed answers please. Thanks in advance.

[The emperor has no clothes]

Well now, informed opinions can be pretty subjective.  But I will tell you from my experience I've had gas in my standard for up to a year before with no bad results.
I'm curious why you log all your gas purchases ?

[Bighead]

If it runs fine you did no damage and run it til empty and refill

[Tfrank59]

I think if you had bad gas you'd know it for sure. It makes your engine run like crap. But if you're going to run your bike that infrequently through the winter you should probably treat the gas with seafoam. Just my 1.5 somewhat-well-informed cents

[Cracker Jack]

I think if you had bad gas you'd know it for sure. It ruins your engine. But if you're going to run your bike that infrequently through the winter you should probably treat the gas with seafoam. Just my 1.5 somewhat-well-informed cents

How do I know whether it's bad? Characteristics/symptoms?
How does it damage the engine? ???

[Tfrank59]

Well I heard a recent case where it ruined at least two engines on the bikes in a motorcycle group – they filled up at this one station and it crapped out their bikes motors. But depending on how the gas is contaminated, like if it's not just water, but dirt and stuff that didn't get filtered out down inside the tanks at the station, it reeks havoc throughout your whole fuel system. Here's a link to read and even though a lot of the stuff applies to fuel injected engines, just think about what it's doing inside of a carburetor as well: http://www.knowyourparts.com/technical-articles/bad-fuel-fact-or-fiction/

[Steel cowboy]

If you don't know the next time you might get to ride the bike, I would suggest using a gasoline conditioner such as Stay-bil, for ethenal fuels. You can also use non ethenal fuel, it will last longer and not draw water as much as ethenal fuel. If you run some Seafoam or similar fuel system cleaner it will keep your tank and carbs. In good shape. I would suggest looking in the tank for rust building up on the bottom, an indicator of problems to come. Water in your fuel system is your worst enemy.
Just starting the bike up and letting it idle only uses the low speed jets, you need to ride it above 2500 rpm's to get the high speed jets working too.

[Hook#3287]

Bad Gas, Yeah, after taco night at the pub

Are you questioning corn gas, old gas, contaminated gas?

What is bad for our bikes, may not be bad for other vehicles, and vise versa.

One day, on a ride, my group met at a breakfast place.  Three of us, me included, filled up at the station close by, at different times, w/o seeing each of us doing it.

We had chow and headed out.

At the next stop, about 5 miles, my buddy behind me honked his horn and told me my bike was smoking.  He was right, and it was smoking bad.

I couldn't think what was causing that amount of smoke.  I thought maybe I burnt a valve or something.  Never heard of that, on this board.

As I'm considering what to do , my buddies HD starts pushing out smoke.  What?

We have to go down the road, couldn't stay where we were and as we pull up to a parking area, another HD starts puffing smoke. WTF?

We start climbing around the bikes like a bunch of agitated monkeys, looking for leaks and who know what else, when we figure out we all got gas at the same place that morning.

We then figured the gas was the culprit and considered draining it out, but out on the road on a Sunday morning, where?

We decided to burn it up, after adding some gas treatment and it took two tanks to clear it out.

Not to be racist, or religist, or whatever, but a turban wearing individual did buy that station a while ago.

Turns out, some diesel was added to the stations gas tanks and the eastern cultured individual didn't do a thing about it, just kept pumping it out.

My understanding is it happened on Friday and he was still contaminating peoples vehicles on Sunday.  It's also my understanding several high end cars fuel injections systems were damaged and a few lawsuits have been filed.

Surprisingly, nobody burnt the place down, yet.

That was BAD GAS

[Hook#3287]

Oh yeah, I forgot.

It's CHEAP INSURANCE to use Stabul Marine, if your bikes gonna sit a while. 

[Paladin528]

My suggestion is that, when the bike sits for any appreciable time, turn the petcock to RES before starting it.  Run it on reserve for several miles then switch back to ON.  This will suck the water contamination into the engine first which will give you a problem in your driveway rather than on the highway.  If there is water, the bike will stumble and misfire and generally run like crap.  it may even stall and be difficult to start. it WILL eventually clear and actual gas will get to the carbs. If you do have water then the best course of action is to add a fuel additive containing ALCOHOL.  the alcohol will mix with the water in the fuel and allow it to remain in suspension in the fuel and be burned in the engine.  Run that tank DRY. then refill with good gas.

[Gryphon Rider]

If you do have water then the best course of action is to add a fuel additive containing ALCOHOL.  the alcohol will mix with the water in the fuel and allow it to remain in suspension in the fuel and be burned in the engine.

Also known as gas line antifreeze, which is designed specifically to absorb water in gasoline.

[Paladin528]

I wouldn't use the word "absorb" it mixes readily with water so as to allow it to burn in the engine without drowning it
But you are correct

[Paladin528]

You can actually do a simple test by taking some regular gasoline and adding a measured amout of water to it.  Shake the crap out of it and you will see the alcohol in the fuel separate out.  This can give you an indication of how much alcohol is in your gasoline if all of the liquids are measured.  so if you are ever curious, try it.

[falconbrother]

We're talking in huge generalities here but..  Most of the time "bad gas" won't hurt your engine.  Old gas just runs like crap till it won't run at all.  What I have observed is that it stays pretty workable for a while but, when it starts to go bad it seems to get worse in a hurry.  If I'm storing mine for more than a couple of months I drain the gas out of it, especially when the temperatures are subject to flux a lot and create water/rust in the tank.  I had an old 1982 Yamaha that I learned the hard way with.  A few minutes of prep can save a ton of cash and days/weeks/months of work.  I use stabil in my old motorhome and have never had an issue.  I drive it twice a month and run the generator.  Sitting for a long time is pretty terrible on gasoline motor conveyances.  The lot where I store my old motorhome is loaded with neglected rigs.   

[Gryphon Rider]

If I'm storing mine for more than a couple of months I drain the gas out of it, especially when the temperatures are subject to flux a lot and create water/rust in the tank.

This is the situation where it is important to keep the tank FULL of gasoline.  It's the moisture in the air that condenses on the inside of the tank, creating rust.  No air means no condensation.

[indybobm]

I'm a firm believer in adding a little Lucas Ethanol Treatment each time I fill up. I add about 1/2 ounce. You never know when your bike will sit for awhile because because of circumstances.

[Jess from VA]

For corn polluted Gas (sitting, or not). (a little goes a long way)

or


For all gas (in full tanks sitting for long periods)
 
The marine grade blue is much better (and costs more, but uses less per gallon) than the regular red.


Then, I always also add one of these two (more than called for, but not the whole jug).



or



And just adding it to the tank when you finally put the bike up is no good unless you run it fully through the fuel system, which means more than 30 seconds.  

And if I think I've got some crud anytime, or just a few times a season I run this. (strongest cleaner)



My closest non-corn fuel is 50 miles door to door, and I get it whenever I can, but I'm still around a gallon and a half light when I get home.

I have twelve 17yo carburetors that have never let me down or been touched (good thing because I might as well try to repair a Saturn Five rocket as a carburetor)

The idea of starting a long sitting bike on reserve is a capital idea.  
Maybe starting on ON, but going to reserve as soon as she's running? (and then paying attention)  

 

[Paladin528]

Water is heavier than gas so settles to the bottom of the tank.  Shaking it up sends that water into suspension.  Best to switch to reserve to suck the bottom of the tank first then switch over to ON.  If my bike sits for more than a day this is my process just in case.  I have never actually had water in my fuel to this point that I know of but being an aircraft Maintenance Engineer for 30 years as well as a pilot, I know the "dangers" of water in fuel.

[chiefrq]

Having had many experiences with stale gas, I can confidently say that mine is an "informed" opinion (although others might disagree). Instead of using additives, I switched to ethanol-free gasoline on all my machines. Whenever possible, I try to stop by small general aviation airports and fill up on 100LL aviation fuel. It has no ethanol and can sit for years without a problem. Aviation fuel costs about twice what you'd pay for regular gas (with ethanol) at the pump. I've never had a problem filling up at small arports. In addition, there's a free app for the iPhone called "Pure Gas." It will give you the locations of gas stations in most areas that sell ethanol-free gasoline. It costs a little more than most gas stations charge but it's well worth it in my opinion. Although I still fill up on regular gas (with ethanol) on occasion, I always be sure my bikes, ATV and other engines are full of aviation fuel before I leave them sit for any length of time- like during the winter. I believe aviation fuel will even clean carbs and smooth out an engine that's been running rough due to ethanol gunk. OK, so you pay a little more for ethanol-free but it's well worth it, in my opinion.

[Paladin528]

Lead will do far more damage than ethanol to your Carbs and valves etc.  100LL stands for Low Lead but it still contains lead.  I wouldn't put it in my bike

[Tfrank59]

good to know.  also a good tip you gave about occasionally using the stuff at the bottom of the tank by switching to reserve.

[Gryphon Rider]

Lead will do far more damage than ethanol to your Carbs and valves etc.  100LL stands for Low Lead but it still contains lead.  I wouldn't put it in my bike

I understood that leaded gas messes up the catalytic converter, not the carbs or valves, and 1500 Valks don't have cats.  It was unleaded gas that could damage valves seats on engines built sometime before unleaded gas was implemented.  As leaded gas became unavailable, you had to have hardened valve seats installed in your old car's engine.  Haven't had to think about this recently, and haven't just Googled it, so I am willing to be corrected.

[Paladin528]

Valve seats must be hardened to use unleaded gas.  Pretty much every engine built in the last 35 years meets that requirement. It will DESTROY an catalytic Converter in very short order.  that is because LEAD is a SOLID.  The heat in the catalytic converter melts that solid and it accumulates on the plates in the converter.  Very bad.  Problem is, it also collects on the valves and will gum up a carb pretty good as well.  It will also foul the plugs over time.
If you are old enough to remember running leaded gas in cars before the advent of fuel injection and unleaded gas you would remember how gummed up an engine would get.
AvGas uses lead still because ethanol has too low a vapour pressure and would cause vapour lock in the fuel lines at altitude.  That is essentially its only advantage over regular old MoGas.  You can run MoGas in an aircraft with the appropriate approvals but there are caveats that come with it.
Remember, Aircraft are subject to STRICT regular maintenance provisions including cleaning of the carbs.  Bikes...Not so much.

[Paladin528]

one other thing with AvGas.  Water WILL NOT mix with it at all.  If you get water in your tank it will settle to the bottom where it is drawn directly into your carbs and engine which has the potential to cause the engine not to start.  With Ethanol fuel 10% or lower the water will mix with the ethanol to some degree and run fine through the engine.
Remember that Aircraft fuel tanks are drained of water before every flight.