Your coworker is crazy. Ever let a lawnmower sit over winter then try to start it in the spring? Same thing happens to gas in a vehicle. Adding Stabil will alleviate some of those problems. Also, if a gas tank isn't completely full, moisture can form due to the cold and then the tank starts to rust. Always fun.

Either drain the gas, put in Stabil, or pay the consequences.. They dont make things like Dry Gas and Stabil for no reason, I would never let my bike sit for any length of time without using an additive to help keep it stabilized. It can break down and cause all kinds of problem described above.

Alot of it depends on how it's stored as well, if its outside, or in a garage, a heated envirnment ?

I think that your coworker may be a little off. If there is one common theme when it comes to winterizing it is that you need to add stabilizer.

is it worse in bikes and lawn mowers than it is with cars? people keep telling me how they let a car sit for a year and had no problems with it. or how they keep a 5gal container of gas in their garage for a year with no problems.

the guy that brought it up has a few 5 gallon plastic containers in his garage, its not heated. i doubt the containers are totally full either.

oh i ment to put this in th elounge not sure why i put it in kat talk ;p

First of all, let us differenciate between sealed and unsealed fuel containers.

All modern cars (since 1974 in the USA) have vapor-sealed fuel tanks, meaning it won't let air (or fumes) out -- hence the sucking noise you sometimes hear when you take off a gas cap on a car. Most fuel containers you'd keep at home for the lawn mower are the same way -- sealed.

Then we have unsealed fuel containers. Almost all motorcycles (there's supposed to be a change on this front with the new EPA regulations), with the exception being the California models (which have a vapor recovery system, but even that isn't totally unsealed, because the carb bowls still have contact with the air from the airbox, which is ambient air). Ditto with leaving a fuel container uncapped in the shed.

So, what happens in the sealed-system? The fuel itself can't evaporate, so it won't lose it's composition that way, leaving only biological contamination as an issue. Plus, the lack of air-exchange tends to keep water content of the tank down (back to this later). Bacterial growth can be a problem, but most car tanks don't take directly off the bottom, plus have extremely good filtering (multiple filters) between the tank and the injectors. And computers that will automatically compensate the spark timing signal to improve whatever is there. This isn't to say the fuel is the same as fresh pump fuel, just that it usually remains viable to some degree or other.

In the open-system, you have to deal with fuel evaporation (leaving paraffin wax residues and other residues, as well as losing the lighter compounds in the fuel mix), condensation from the newly introduced air (tank expands & contracts with heat/cold cycles, effectively cycling the air -- and humidity -- in the free space in the tank). And you now not only have the same bacterial growth issues, but you also have a new avenue of introduction of such bacteria/algaes/etc -- via the air moving in and out. The most harmful bacterial degeneration of gasoline normally happens at a water/gasoline boundary, where the bacteria & petrol-eating algae forms can exist in contact with both mediums. Thus, the fuel in this scenario is being attacked by multiple potential problems, resulting in a much faster degeneration than a typical car's gas tank or sealed fuel tank...

Given that information, you can figure the rest out for yourself.

Cheers,
=-= The CyberPoet

GAS GOES BADDDD!!!!!!!!

As stated above gasoline goes bad. It's better to be safe than sorry so that's why I use stabilizer. The question is now is using stabilizer detrimental to the quality of the fuel or long term engine parts? I only intend to use it if the bike sits for a season.

Gas does indeed go bad...

Usually it starts by hanging out with the wrong crowd... Doing a little drugs... And then a little peer pressure and it's in a gang that robs a small asian couple trying to make ends meet with their small grocery store... kills a cop while running from the robbery... And then ends up on death row, a murderer...

Fox had a special on it a while back... "The Gas that Goes Bad, and the Women That Love It."

Really... I kid you not...

I know that with GM vehicles, with key off, vent is on. Meaning that while the vehice is sitting, key off, that the fuel tank is venting to atmosphere.

STA-BIL. Know it. Love it.

As many times as I have taken off my carbs, USE A STABILIZER! GAS GOES BAD!
Cars are totally different than bikes, especially newer cars vs. older bikes. One has fuel injectors and the other has some DAMN carburetors. Be careful.

-Sam

Gas does go bad. I bet in a warm climate like AZ the gas will evaporate quicker leaving heavier components in gas and more problems. The other thing is bike carbs have small little jets, and gas turning to varnish quicker will be a bigger problem, since the jet opening is so small to begin with. Compared to a 73 pontiac with 400 CI enigne and its fuel jets in the carb. I have seen old cars start up after sitting for 8 months and the engine doesn't care that much. Bikes, lawn mowers, snow mobiles, not the same thing.

The US regulations require that the fuel cap for cars act as an one-way valve (permit air into the thank when the tank is under a certain amount of vacuum as fuel gets consumed), but not out. This is because venting of fresh fuel vapors from a single car -- say a '68 stang parked in the sun -- puts out more pollution than a dozen properly tuned cars running even without catalytic converters. Thus, if your '74+ GM tank is venting fumes when off, it means something is defective or the system has been modified somehow from US EPA-mandated requirements (such as adding an aftermarket replacement gas cap without the venting built-in). There is no system in GM's that unlock the simple spring-controlled gas cap vent on their various vehicles in response to the key position.

Cheers
=-= The CyberPoet

Your talking about the gas cap.
I am talking about the evap vent valve post charcoal canister.
GM has a spec that says a vehicle has to sit for 40 days without the battery dropping below a certain voltage. If the vent valve was energized, meaning it closed, for the 40 days, the voltage would not meet our spec.

While the vehicle is parked, the fuel system is not sealed. sure, the gas cap is sealed, but the vent valve is open.

I don't know which car you're thinking of (and you may know something I don't) -- the only GM cars I've owned were a '74 Nova (350 V8 ) and a '79 Cadillac Coup (425 V8 ). In both cases, the charcoal cannister was connected to the carb bowls (very similar to the routing on the California spec Kats) and not to the gas tank... unless there was another cannister I never found...

Hmmm...


Cheers,
=-= The CyberPoet