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Sporty fuel stuff up

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  • Amberwhiskey
    Amberwhiskey
    4 years ago
    Brain fart time.  Accidently filled my 2016, EFI 1200 Sportster with 91 unleaded along with my wife's Street 500.
    The 500 can run on 91 but the Sportster's recommended fuel is 95 or higher.  The fuel light was not on but close so 
    I probably now have a mix of 4 litres of 95 & 13 litres of 91.

    Most of my riding is with my wife so my bike doesn't cop a hammering.  Would it be ok to carry on & top up with 
    98 as I use, say, each quarter of a tank & gradually get back to the proper fuel?  I would rather not mess about with 
    siphoning fuel but I could re-use it in my car.  Opinions?

  • HOG63
    HOG63
    4 years ago
    [Deleted]
    Hmm, seems there’d be no probs from the comments below. 
    Good to know. 
  • paulybronco
    paulybronco
    4 years ago
    Quoting Amberwhiskey on 03 Jun 2019 10:04 AM

    Brain fart time.  Accidently filled my 2016, EFI 1200 Sportster with 91 unleaded along with my wife's Street 500.

    The 500 can run on 91 but the Sportster's recommended fuel is 95 or higher.  The fuel light was not on but close so 
    I probably now have a mix of 4 litres of 95 & 13 litres of 91.

    Most of my riding is with my wife so my bike doesn't cop a hammering.  Would it be ok to carry on & top up with 
    98 as I use, say, each quarter of a tank & gradually get back to the proper fuel?  I would rather not mess about with 
    siphoning fuel but I could re-use it in my car.  Opinions?

    Just ride it , bet you wont notice the difference other than less klm to the tank full. 
  • Ratbob
    Ratbob
    4 years ago
    All good, won’t hurt the bikes. There are times in small country towns where all you can get is 91. I usually run 95 in my 110 TwinCam and often 98 if it’s all they have. All I seem to notice is that 91 burns up a bit faster, 98 lasts longer. 
    I’m with Pauly, I don’t reckon anyone could ride a bike and tell you what fuel’s in it, er unless it’s 110 Avgas. 
  • robnicko
    robnicko
    4 years ago
    just ride it and dont worry about it. It will be fine


  • mickle
    mickle
    4 years ago
    Wont hurt at all, someone in here ran their M8 on Diesel, didn't die.
  • Birtyyy
    Birtyyy
    4 years ago
    Quoting mickle on 04 Jun 2019 12:58 AM

    Wont hurt at all, someone in here ran their M8 on Diesel, didn't die.

    Seriously?!?!
  • mickle
    mickle
    4 years ago
    Quoting mickle on 04 Jun 2019 12:58 AM

    Wont hurt at all, someone in here ran their M8 on Diesel, didn't die.

    Quoting Birtyyy on 04 Jun 2019 01:08 AM

    Seriously?!?!

    Wasn't 100% diesel, he topped his tank up and continued to ride wondering why it was making weird rattles and noises, turned around
    to the dealership where they discovered the mistake. Drained the tank, fresh fuel and on his way again.
  • tussuck
    tussuck
    4 years ago

    My goodness your WAY overthinking this think matey.  Its just friggen petrol and your NOT going to blow up the bike with what you have done.

    Who said you needed to use 98 all the time in the first place as pretty much anything 91 and above is going to be fine given the compression ratios those engines run.  I would shy away from anything lower, BUT even then it would still work in an emergency, but you might get some slight pinging if the motor loads up too much.

  • JFE
    JFE
    4 years ago
    Quoting mickle on 04 Jun 2019 12:58 AM

    Wont hurt at all, someone in here ran their M8 on Diesel, didn't die.

    Obviously not a diesel car owner - you can always tell with the smell and slipperiness of the diesel bowser.
    Others are right 91 is no issue. Just don't make a habit of it if it's meant for higher octane fuel. And stay away from ethanol.
  • Amberwhiskey
    Amberwhiskey
    4 years ago
    Thanks Gents, ride on it is!  
    I'll keep an ear out for pinging & back off if needed but riding with the wife it leads an easy life.
  • mickle
    mickle
    4 years ago
    Quoting Amberwhiskey on 04 Jun 2019 08:41 AM

    Thanks Gents, ride on it is!  

    I'll keep an ear out for pinging & back off if needed but riding with the wife it leads an easy life.

    When it gets down a bit just top it back up, old mate in the servo once told (as he had no 95) half tank of 98 plus half a tank of 91
    and ya got 95.
  • beaglebasher
    beaglebasher
    4 years ago
    Be interested to know what is the actual difference between 91 and 98.  In scientific lay-mans terms.
    Cant be bothered googling it but if somebody can explain it that would be great

  • mickle
    mickle
    4 years ago
    Quoting beaglebasher on 04 Jun 2019 09:52 AM

    Be interested to know what is the actual difference between 91 and 98.  In scientific lay-mans terms.
    Cant be bothered googling it but if somebody can explain it that would be great

    I Googled it for you.
    Those numbers – 91, 95 and 98 – are the so-called ‘octane rating’ of the fuel. They’re all about the same in terms of the energy in the fuel. What octane really is, is an index of a fuel’s resistance to burning too early inside your engine – if that happens, it causes ‘pinking’ or ‘pinging’ (same thing), which is mechanically destructive at high revs and large throttle openings.
  • beaglebasher
    beaglebasher
    4 years ago
    Quoting beaglebasher on 04 Jun 2019 09:52 AM

    Be interested to know what is the actual difference between 91 and 98.  In scientific lay-mans terms.
    Cant be bothered googling it but if somebody can explain it that would be great

    Quoting mickle on 04 Jun 2019 11:03 AM

    I Googled it for you.
    Those numbers – 91, 95 and 98 – are the so-called ‘octane rating’ of the fuel. They’re all about the same in terms of the energy in the fuel. What octane really is, is an index of a fuel’s resistance to burning too early inside your engine – if that happens, it causes ‘pinking’ or ‘pinging’ (same thing), which is mechanically destructive at high revs and large throttle openings.

    Cheers for that mick.  Does that mean 98 will combust sooner or later than 91?
  • brash
    brash
    4 years ago

    it has more detonation resistance.

    Ride the bike with 91 until it runs out, avoid hot weather or lugging the engine under load. It will live. Non event.


  • Nutty
    Nutty
    4 years ago
    Quoting beaglebasher on 04 Jun 2019 09:52 AM

    Be interested to know what is the actual difference between 91 and 98.  In scientific lay-mans terms.
    Cant be bothered googling it but if somebody can explain it that would be great

    Seven. :-)
    Our retail octane numbers are RON (ping resistance) + MON (HP production) /2

    As we go up in retail octane numbers we get a little more HP out of the fuel...but...it burns slower. 
    This allows the ECU to throw a fair bit more spark advance at the motor at lower RPMs, in the correct engine configuration this can make more low-end HP and torque. 
    Anti-ping additives do SFA in the high RPMs because the pumping losses associated with big amounts of spark advance kill the HP. 
    98 makes good power in undersquare motors with short flame-front paths, in big-bore oversquare motors it kills HP at higher RPMs. 
    In 250 2Ts 95 will make more HP than 98...
    Haven't done specific fuel comparison dyno-pulls on HDs so can't comment there but generally massive bores and low compression love 91.
    I tuned my M8 on 91 octane. Made 90HP and 118Tq with the stock cam. I'm always out in BFN so it was imperative to tune on 91.
    Hope that helps.
  • tussuck
    tussuck
    4 years ago
    I run 91 Regular in my 09 Sporty and shes at 100,000kms with no issues.  Mind you I have a Thundermax with Autotune which helps things settle down into the different fuels etc.
  • beaglebasher
    beaglebasher
    4 years ago
    Quoting beaglebasher on 04 Jun 2019 09:52 AM

    Be interested to know what is the actual difference between 91 and 98.  In scientific lay-mans terms.
    Cant be bothered googling it but if somebody can explain it that would be great

    Quoting Nutty on 04 Jun 2019 11:21 PM

    Seven. :-)

    Our retail octane numbers are RON (ping resistance) + MON (HP production) /2

    As we go up in retail octane numbers we get a little more HP out of the fuel...but...it burns slower. 
    This allows the ECU to throw a fair bit more spark advance at the motor at lower RPMs, in the correct engine configuration this can make more low-end HP and torque. 
    Anti-ping additives do SFA in the high RPMs because the pumping losses associated with big amounts of spark advance kill the HP. 
    98 makes good power in undersquare motors with short flame-front paths, in big-bore oversquare motors it kills HP at higher RPMs. 
    In 250 2Ts 95 will make more HP than 98...
    Haven't done specific fuel comparison dyno-pulls on HDs so can't comment there but generally massive bores and low compression love 91.
    I tuned my M8 on 91 octane. Made 90HP and 118Tq with the stock cam. I'm always out in BFN so it was imperative to tune on 91.
    Hope that helps.

    Cheers Nut. That does help my understanding a little bit.    I  think???
    Never heard the terms undersquare or oversquare before. Whats that?
  • Ratbob
    Ratbob
    4 years ago
    Quoting beaglebasher on 04 Jun 2019 09:52 AM

    Be interested to know what is the actual difference between 91 and 98.  In scientific lay-mans terms.
    Cant be bothered googling it but if somebody can explain it that would be great

    Quoting Nutty on 04 Jun 2019 11:21 PM

    Seven. :-)

    Our retail octane numbers are RON (ping resistance) + MON (HP production) /2

    As we go up in retail octane numbers we get a little more HP out of the fuel...but...it burns slower. 
    This allows the ECU to throw a fair bit more spark advance at the motor at lower RPMs, in the correct engine configuration this can make more low-end HP and torque. 
    Anti-ping additives do SFA in the high RPMs because the pumping losses associated with big amounts of spark advance kill the HP. 
    98 makes good power in undersquare motors with short flame-front paths, in big-bore oversquare motors it kills HP at higher RPMs. 
    In 250 2Ts 95 will make more HP than 98...
    Haven't done specific fuel comparison dyno-pulls on HDs so can't comment there but generally massive bores and low compression love 91.
    I tuned my M8 on 91 octane. Made 90HP and 118Tq with the stock cam. I'm always out in BFN so it was imperative to tune on 91.
    Hope that helps.

    Quoting beaglebasher on 05 Jun 2019 08:16 AM

    Cheers Nut. That does help my understanding a little bit.    I  think???
    Never heard the terms undersquare or oversquare before. Whats that?

    If you imagine a piston going up and down a square engine is where the diameter of the piston equals the length of the stroke (up and down distance not added together) An under square engine has a stroke that is less than the bore. These are usually more low torque, high revving power engines. An over square engine means the stroke is longer than the bore, so more up down distance which typically gives you greater torque over power. You may have heard of engines that have been stroked, gives em more torque. Oops, just realised I’ve hijacked the post, no matter. Over to you Nut, hope I’m correct. :)
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