Ultra 94 in the tank over winter | GTAMotorcycle.com

Ultra 94 in the tank over winter

JonnyWyshbone

JonnyWyshbone

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Somebody once told me it's a bad idea to leave high octance fuel over the winter(Im pretty sure person who told me was making a point about Sunoco/Petro's Ultra 94). He never did provide a reason as to why this was. Can anyone shed light on this? My 07 zzr600 states right on the tank 91 and over, so I figure by putting the 94 in all the time I was doin the bike a favor.:confused:
 
Whoever told you doesn't know what they're talking about.

Higher octane fuel only has a higher burning temperature so for high compression engines, you don't get knock.

Whether fuel is 87 or 94, leaving it over winter without fuel stabilizer is bad and can cause the gas to gum up.
 
I believe it was only due to the ethanol content.
Some people are very picky about certain stuff and I heard it was better to leave (I believe) shell's higher octane 91 as it is ethanol free.
As for the reason of no ethanol, I'm sure someone will chime in that knows a little more then me.
 
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There is a lot of misguided information regarding fuel, octane, ethanol etc. Fuels with ethanol are prone to develop condensation from heat cycles from being stored. Some fuels, possibly Petro's 94 may contain ethanol and maybe subject to this issue.

I've never had an issue with my lawn mower, snow blower or motorcycles after putting in fuel stabilizer when stored. Regardless of the brand. Just make sure the tank it full, the proper amount of stabilize is added and run through the system and you should be good to go.
 
braveheart said:
how is this related to insurance ?
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He's worried about insurance figuring out that he uses the wrong fuel in his bike --> high risk IMO
 
jay-d said:
Whoever told you doesn't know what they're talking about.

Higher octane fuel only has a higher burning temperature so for high compression engines, you don't get knock.

Whether fuel is 87 or 94, leaving it over winter without fuel stabilizer is bad and can cause the gas to gum up.
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I believe high octane fuel does not have a higher burning temperature. It has higher resistance to detonation.
 
matthew said:
I believe high octane fuel does not have a higher burning temperature. It has higher resistance to detonation.
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This is correct. Further to that, octane does not make hp. Case in point, mr12, generally regarded as a very powerful race fuel, is rated at 87 octane. Certain race fuels will do damage if left in the tank for even a few days. This does not apply to pump. Check vp fuels web-site for mor fuel info.
 
Another question along the same lines.

If you have a plastic gas tank i.e. Triumph Sprint, would it be advisiable to completely drain the tank?

I understood the main reason for keeping the tank full with stabaliser was to prevent condensation and hence rust in a metal tank, which would be a concern with a plastic tank.

I have always left the tank full and used stabaliser, just wonder if that's necessary.
 
ethanol in fibreglass (ie, boat) tanks can eat the resins away and cause major problems.

as time goes on, this has been spreading (to those uninformed) to include all gas in any tank
 
Some manufacturers have been having issues with plastic gas tanks - Ducati, for one.

I prefer to store over the winter with the tank bone dry and sealed, and in a climate-controlled environment. Can't have condensation or rust if no air goes in or out of the tank, and air doesn't go in or out of the tank if it stays close to the same temperature.
 
JonnyWyshbone said:
Somebody once told me it's a bad idea to leave high octance fuel over the winter(Im pretty sure person who told me was making a point about Sunoco/Petro's Ultra 94). He never did provide a reason as to why this was. Can anyone shed light on this? My 07 zzr600 states right on the tank 91 and over, so I figure by putting the 94 in all the time I was doin the bike a favor.:confused:
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They were referring to the ethanol in the fuel, not really the octane rating. Only Ultramar 91 and Shell 91 contain no ethanol, every other grade and brand DOES!

You do NOT want to store your bike over the winter with Ethanol based fuel. It degrades quickly and leaves behind a hard varnish that will make your injectors stick, clog the nozzles, etc. Once I stopped using Sunoco 94 over the winter and started using Shell 91, NO PROBLEMS! woot :)

Turbo gpz said:
This is correct. Further to that, octane does not make hp. Case in point, mr12, generally regarded as a very powerful race fuel, is rated at 87 octane. Certain race fuels will do damage if left in the tank for even a few days. This does not apply to pump. Check vp fuels web-site for mor fuel info.
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Yikes! I didn't know MR12 was only 87 octane!!! I better back off the timing advance when I give her a rip :)

-Jamie M.
 
I know it's an endless debate, but before I realized the OM suggested 91, I was using the cheapest swill. Can't imagine there wasn't ethanol in it. Never got around to winterizing the scoot since I was working on it. Didn't gas up for three months. Started twice for oil/coolant changes. Forgot about it. Started up with no problems in the Spring, even with a non-tended battery.

Maybe some blends pair the ethanol with another additive that causes problems when left to sit? My tank is some sort of plastic and the Burger is fuel-injected.
 
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Brian P said:
Some manufacturers have been having issues with plastic gas tanks - Ducati, for one.

I prefer to store over the winter with the tank bone dry and sealed, and in a climate-controlled environment. Can't have condensation or rust if no air goes in or out of the tank, and air doesn't go in or out of the tank if it stays close to the same temperature.
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+1
I drain it vent it dry then put it in the basement open.
 
Turbo gpz said:
Further to that, octane does not make hp. Case in point, mr12, generally regarded as a very powerful race fuel, is rated at 87 octane.
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This is not really correct. It's rated at 87 MON octane. The octane rating you see at our gas stations (87/89/91/94) is the AKI octane rating (RON+MON/2). It looks like MR12 is approx 98 octane AKI when tested against comparible regular fuels.

-Jamie M.
 
Before storage, I brought a bottle Sta-Bil to the local shell station and added it to the tank before my last fill. I then filled it as full as I could with V-Power (94?). At the time, the pump said that the highest grade contained no ethanol (up to 10% for the 87, and up to 5% for the 91).

When I got home, I topped up the tank with Seafoam.

Someone had mentioned in one forum or another that gas loses octane during storage, and that 94 will end up at around 87 after a few months. I added the Sta-bil and Seafoam in to resist any moisture or residual ethanol from the 87 octane I usually put in the tank.

Overkill? Maybe. But I don't think I'm harming anything.
 
V-Power is Shell 91?? No ethanol in that. Seafoam is probably all you need. The Stabil stuff is garbage when used in fuels that contain ethanol.

-Jamie M.
 
toysareforboys said:
V-Power is Shell 91?? No ethanol in that. Seafoam is probably all you need. The Stabil stuff is garbage when used in fuels that contain ethanol.

-Jamie M.
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Yeah - I couldn't remember off of the top of my head. 87 (10%), 89 (5%), 91 (v-power, none).

I was told that the marine version (blue) of the Sta-bil was better. It's what I used in combination with the 91, no-ethanol gas and the Seafoam.
 
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