STP Gas additive, Trying to understand !

Discussion in 'Engine, Fuel and Exhaust' started by Honest Abe, Oct 14, 2010.

  1. Honest Abe

    Honest Abe Member

    So my bike has 21K on it, and recently completed the 20K service at the dealer, which included replacing the fuel filter.

    So I'm filling up and figure let me pour a bottle of this
    in the tank as I'm filling up. I ride away and as soon as the bike starts it feels smoother. The more I rode, the more I enjoyed my bike and how it did not have the rough idle and motor vibration. So the tank needs to be filled up again, and this time I figured we cleaned the fuel injectors...etc. We will just run with straight gas 91 octane from Union 76.

    My bike lost it's smoothness! Anyone had similar experience? I would love to have my bike run all the time with the STP in it. It is a much more enoyable ride, but concerned what damage it may do longterm to the motor....

    Any Ideas?
  2. Dr.Evil

    Dr.Evil Junior Member

    I thought that stuff had a ratio of one bottle to 10-15 gallons of fuel. Did you actually use a whole bottle in 4-5 gallons? If it reduced the vibration in the motor, then it ran more like a Goldwing? I would not like that at all.
  3. Honest Abe

    Honest Abe Member

    Yes I did use the whole bottle, I have been know to dump a whole bottle of seafoam in the Gas Tanks from time to time. But seriously ! it was not like a metric, or goldwing, but it was quick, responsive and felt more nimble. Less hesitation I guess... Just really liked how it ran.:D:)
  4. ultrat

    ultrat Senior Member Contributor

    I'm thinking it upped the octane rating mabe...
  5. Honest Abe

    Honest Abe Member

    Me like your explanation Ultrat. :)
    Even though it may say 91 Octane,
    gas quality could be poor, and I heard harley like higher Octane gas anyway...

    Try STP octane booster additive I will do. And Noticeable Improvement I hope to see. (Yoda Dialect used in case you notice not)!:s

    and if that does the trick, I will report back. You have got to try it to know what I'm talking about. I would even stick my neckout and say a 50% improvement in responsiveness and smoothness.
  6. Jack Klarich

    Jack Klarich Guest

    The only problem I see here is the engine may get used to this boost, and am wondering the long term action on the injectors. I used HD Duralt for years in my Evos, I am leary of any thing added to my gas any more tho there is too much junk in the gas now catch 22 IMO
  7. maine-e-axe

    maine-e-axe Junior Member

    Most injector cleaner's have alcohol in them and it is hard on the O rings in the injectors I was told.
  8. Jack Klarich

    Jack Klarich Guest

    Very good point, the newer o ring material is suppose to be user friendly with alcohol, I dont trust the off the shelf cleaner I have my doubts it works the way they say it does. We use CAT products @ work made by Run Rite, they work good as the cleaner is high concentrated Techron, tho as Hoople said in an earlier post too much can get past the rings and cause major problems JMO
  9. mouthful

    mouthful Active Member

    Across the country Ethonal is becoming common place up to 10% and hear say has it Uncle Sam wants to make it up to 15%. May be a little octane booster in the right measured dose per tank might become the norm for these high octane Iron Horses we all have such a passion for.
  10. NEWHD74FAN

    NEWHD74FAN Experienced Member Retired Moderators

    Using Gas Treatment in too high concentration may stress seals in the injection system, but in at proper level should not hurt. But it is not gasoline, so actual performance may suffer as it by quantity displaces the designed proper gas fuel mixture.

    Maybe there was an improvement, but more likely it is the contrast of poor gas...just because a station advertises 93 octane does not mean it is fresh in the underground tank. Better to find a good major fuel supplier that turns product quickly.