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gasoline with 10% ethanol in my 1992 K75 OK?

keither

keither
I've just acquired a sweet little K75 with only 31000 miles and in excellent shape. It runs great and no porblems. I noticed in the shop manual that gas with ethanol is not recommended; do we have a choice? What additives can we use to keep the ethanol from damaging th fuel system? Maybe upgrades have been made available?
K75, Christmas cactus bloom, 027.JPG
 
SWEET!

You really don't have much choice any more. Not really a problem unless you let the bike sit long enough for the fuel to breakdown. If the fuel separates, it will attack and dissolve the rubber vibration damper that holds the fuel pump inside the gas tank. The gunk will get sucked into the pump and injectors and kill them. You should have no problem if you regularly ride it (something the previous owners might not have done with that low mileage).



:dance:dance:dance
 
Put some Stabil Marine fuel stabilizer in the tank. It has a fuel dryer that helps keep the ethanol in the gas from absorbing water.

David Sword
 
Use Stabil if storing the bike, otherwise ride it a lot. Check around there are a few places where ethanol free gasoline is available. You can look here for help: http://pure-gas.org/
PS: nice looking bike. Love the colour.
 
ethanol gas

SWEET!

You really don't have much choice any more. Not really a problem unless you let the bike sit long enough for the fuel to breakdown. If the fuel separates, it will attack and dissolve the rubber vibration damper that holds the fuel pump inside the gas tank. The gunk will get sucked into the pump and injectors and kill them. You should have no problem if you regularly ride it (something the previous owners might not have done with that low mileage).



:dance:dance:dance

Thanks for the info, dont worry, I'll ride a lot
 
As far as additives, our friendly local BMW store's parts department ran in interesting experiment. They mixed gasoline with the recommended percentage of each fuel additive they could find. Each mix got put in a glass jar, with about 1/4" of air at the top, and a nail was dumped in, then the jars were sealed with tape around the cap edge.

They wanted to see if any of the additives prevented rust with the idea that rust would only occur if separation of the gasoline and ethanol occurred. Only one stood out for a good reason. One other stood out for a bad reason.

Stabil wasn't awful, but some rust did start on the nail. SeaFoam was a clear looser - the nail was covered with rust and the mixture had rust flakes in it. They had one jar with just gasoline in it - it was clearer than the jar with the SeaFoam/gasoline mix. The one that seemed to prevent rust entirely was called "K100-MG" (www.k-100.com - I looked on the bottle in my garage.) I forget what the other additives were - but they were commonly available ones. The dealership stocks both the K-100 and the Stabil, but their suggestion to me was to use the K100.

Was this an unbiased test? Probably - the parts guy was pretty proud that they'd come up with it. Was it scientific - probably not as rigidly as I would like, but it did show some results, and the bad results were quite impressive, even more-so than the good results.

Will it help with the separation that damages the rubber components in the K bikes? Dunno - be interesting if someone has some to mix up with some gasoline and dump a bit of the in-tank fuel line into for a while, to see what happens to it (along with another bit in untreated gasoline for a comparison.)

It went in my tank when I wasn't able to ride for 7 weeks (slightly broken leg), and it's in my snow-blower and generator tanks. Can't say if it's doing anything good or bad since I have no A vs B comparison setup, but I'm hoping it's helping to preserve the gasoline in those tanks. I'm back to riding the bike enough that it isn't a worry right now..
 
Don,
Do you know if the Stabil used in the test was the regular red stuff, or the dark Marine Stabil? The Marine version is the only one with a drying agent and is made to help with ethanol problems in marine engines. The pink stuff is just for fuel longevity.

David Sword

As far as additives, our friendly local BMW store's parts department ran in interesting experiment. They mixed gasoline with the recommended percentage of each fuel additive they could find. Each mix got put in a glass jar, with about 1/4" of air at the top, and a nail was dumped in, then the jars were sealed with tape around the cap edge.

They wanted to see if any of the additives prevented rust with the idea that rust would only occur if separation of the gasoline and ethanol occurred. Only one stood out for a good reason. One other stood out for a bad reason.

Stabil wasn't awful, but some rust did start on the nail. SeaFoam was a clear looser - the nail was covered with rust and the mixture had rust flakes in it. They had one jar with just gasoline in it - it was clearer than the jar with the SeaFoam/gasoline mix. The one that seemed to prevent rust entirely was called "K100-MG" (www.k-100.com - I looked on the bottle in my garage.) I forget what the other additives were - but they were commonly available ones. The dealership stocks both the K-100 and the Stabil, but their suggestion to me was to use the K100.

Was this an unbiased test? Probably - the parts guy was pretty proud that they'd come up with it. Was it scientific - probably not as rigidly as I would like, but it did show some results, and the bad results were quite impressive, even more-so than the good results.

Will it help with the separation that damages the rubber components in the K bikes? Dunno - be interesting if someone has some to mix up with some gasoline and dump a bit of the in-tank fuel line into for a while, to see what happens to it (along with another bit in untreated gasoline for a comparison.)

It went in my tank when I wasn't able to ride for 7 weeks (slightly broken leg), and it's in my snow-blower and generator tanks. Can't say if it's doing anything good or bad since I have no A vs B comparison setup, but I'm hoping it's helping to preserve the gasoline in those tanks. I'm back to riding the bike enough that it isn't a worry right now..
 
I have also heard that ethanol doesn't separate like it used to when they first started using it in gasoline. Back in the 80's, I had a car that could NOT use gas with ethanol in it or else the rubber parts on the accelerator pump inside the carburetor would break down. I rebuilt that carburetor twice before reading an article in the local paper about what ethanol in gas could potentially do. I searched out stations that sold gas without ethanol, and the problem was solved.

Here in Minnesota, I burn ethanol gasoline in my airhead and oilhead all the time. The biggest downfall I've ever experienced is that my gas mileage is down a bit from using gas without ethanol. The bikes seem to run just fine, though, and I've not had any rubber bits break down.

Living in Texas, just ride that motorcycle and I would think you'll be fine.
 
When I am on the road and switch from pure gas to ethanol or back, as I ride off I feel a slight stumble, then some softness in throttle that goes away when the o2 kicks in, which is easy to feel from the slight surge that comes back.

Nothing dangerous, just can feel it.

Rod
 
When I am on the road and switch from pure gas to ethanol or back, as I ride off I feel a slight stumble, then some softness in throttle that goes away when the o2 kicks in, which is easy to feel from the slight surge that comes back.

Nothing dangerous, just can feel it.

Rod
 
Don,
Do you know if the Stabil used in the test was the regular red stuff, or the dark Marine Stabil? The Marine version is the only one with a drying agent and is made to help with ethanol problems in marine engines. The pink stuff is just for fuel longevity.

David Sword
Dunno what they used in the test - but what they were selling was the marine version.
 
That just happened to be where I found the MSDS. I would think it unlikely that he would falsify an MSDS, but I suppose requesting one from the manufacturer would be prudent. Interesting though, what we dump into our fuel tanks sometimes.
 
...snip... I noticed in the shop manual that gas with ethanol is not recommended; ....snip
View attachment 42565

To which manual are you referring? I have the Clymer manual and can't find an ethanol reference.

I read on one of the K-bike sites that the rubber fuel tank mount can degrade over time, so you might want to check that. I use ethanol, but have only about 30K miles on my bike. The mount was OK when I checked it a year ago. IIRC, the replacement mount has been upgraded to be ethanol resistant.

Hope this helps.
 
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