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Discussion in 'Norton Commando Motorcycles (Classic)' started by Atlas Commando, Apr 15, 2018.

  1. MexicoMike


    Jan 31, 2010
    If it's a concern you could always drain the tank and then pour that into your closest car's tank. I bought a new in '08 FG fastback tank from Burton's Bike bits. They said it was made with ethanol-resistant resin but I Caswell-coated it before filling it the first time anyway. No signs of any problems yet.

    I have always used 87 octane in my Commando with no sign of detonation using factory-spec timing setting. As noted, performance-wise , higher octane fuel than the engine needs won't do anything but lighten your pocketbook.
  2. Craig

    Craig VIP MEMBER

    Dec 20, 2005
    I went down to local bike shop last week and got a 5 gal. can of 114 octane racing gas ... the boys say pure gasoline none of the corn stuff, put a half gallon in with some pump high test trying to get around 100 test ... starts and runs fine but weather still not cooperating, looks like next week will be good FG tank seems fine so far .... also nice decal on can say contains lead , who knew
  3. Danno


    Feb 7, 2010
    Oh I don't know, I guess the same reason I like to throw money away on leaky old British twins when I have a fast, comfortable, perfectly reliable motorcycle that takes me all over the country and I have less stuck in it than either of my two Nortons. I must be outta my mind.
  4. RoadScholar

    RoadScholar VIP MEMBER

    Dec 28, 2008
    A very good point. I had 5 gallons of drunken 89 that I kept too long for my generator, but I live about 1.5 miles from one of two Massachusetts fire fighting academy's. So, I called them, they burn stuff up al the time, I figured that gasoline would be something that they practiced with. They didn't want it! Go figure.

    It took almost two years for it to evaporate.
  5. MikeM


    Jun 1, 2011
    I drained the tank for the first 3 years I had it running. Everytime I got home, I drained the tank. Got tired of doing that and finally picked up a steel repop tank. Its not perfect but I no longer have to drain.
  6. Atlas Commando

    Atlas Commando VIP MEMBER

    Feb 27, 2018
    Thanks for the info MikeM. It sounds like draining will protect the tank, long enough to find a steel tank if I decide to keep the bike longer term. Present plan is to ride it a few hundred miles and then find a worthy owner who can enjoy making further improvements.
  7. elefantrider

    elefantrider VIP MEMBER

    Apr 6, 2013
    What about Sta-Bil storage additive? Does that work to prevent deterioration of the fiberglass tank?
  8. ewgoforth


    May 23, 2010
    I've been running a '72 fiberglass interstate tank on my 1973 850. Try https://www.pure-gas.org/ for stations that have alcohol free gas, they have the octane rating on msny stations too.They also have cellphone apps. I almost never put alcohol in my tank.

    On long trips I ride until I'm low on gas then find my nearest alcohol free pump. Easier to do with an interstate tank though. Also since I have an 850, 89 octane is all I need. I've seen a few alcohol free pumps that dispense 87, but most are 89 or more.
    Last edited: Apr 18, 2018
  9. Danno


    Feb 7, 2010
    I don't think so. The new blue stuff is supposed to mitigate ethanol separation, but the only thing that protects old fiberglass tanks is to not pour any ethanol in them.

    Be happy you don't have a plastic-tanked Ducati. Ethanol makes them swell up so bad the mounting holes don't match. Alloy replacements are around $2500.

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