what do you do
Road Warrior
Joined: Oct 2012
Posts: 1,371
Likes: 46
From: In the foothills of southwestern NC - US of A
If you've got an EFI bike, buy a Power Vision tuner, and create two MAPs using autotune basic...one created using your usual 9[x] octane, the other for 89 or 87. If you then find yourself in a situation where your preferred octane isn't available on a long trip beyond your usual range, you can spend a whopping 5 minutes on the side of the road or in the gas station parking lot to use the PV tuner to reflash your ECM from one MAP to the other and be on your way, until such a time that you're 9[x] octane is available once again...this is just one of the many beauties of the PV tuner...
=8^)
=8^)
Ultimate HDF Member
Joined: Apr 2014
Posts: 6,322
Likes: 2,500
From: Tennessee
Just fill it up with what's available and go....
My Dyna has 10.5 to 1 compression and quite a few other performance mods and I have had to fill with 89 octane on numerous occasions, it's never caused any issues.
Y'all worry too much!
My Dyna has 10.5 to 1 compression and quite a few other performance mods and I have had to fill with 89 octane on numerous occasions, it's never caused any issues.
Y'all worry too much!
Seasoned HDF Member
Joined: Aug 2011
Posts: 11,814
Likes: 5,120
From: SW Ohio
Put fuel in it and ride it. Try not to lug the engine and don't sit and idle for long periods if you can help it. Without going into boring detail, lower octane fuel detonates more rapidly then higher octane. The hotter the ambient and engine the temp the greater chance for detonation and/or pre-ignition. If using low octane fuel bothers you, NEVER travel to Alaska or deep into Mexico. I've put fuel in my Dyna that was one step above moose **** because if it's between that bike taking it on the chin and me walking; I ain't walking.
Last edited by Campy Roadie; Jul 9, 2014 at 04:40 AM.
Seasoned HDF Member
Joined: May 2008
Posts: 21,132
Likes: 12,693
From: South Carolina
Don`t confuse Detonation with Pre Ignition, they are not the same thing...
Last edited by Dan89FLSTC; Jul 7, 2014 at 11:19 AM.
6th Gear
Joined: Jul 2014
Posts: 13
Likes: 0
From: Ottawa
Pinging will pound the snot out of your crank pin over time. If you're using octane booster, do not use the stuff for racing but use the stuff for street use. The racing stuff has a little nitro in it. Not good for engine longevity.
But I have filled with lower octane on my old 10.5:1 2001. plenty of times but I would never turn down 91 or better whenever it is available. It never hurt anything.
But I have filled with lower octane on my old 10.5:1 2001. plenty of times but I would never turn down 91 or better whenever it is available. It never hurt anything.
Road Master
Joined: Sep 2007
Posts: 778
Likes: 4
From: Opposite Side of the Planet
Yes...this...
Seasoned HDF Member
Joined: Aug 2011
Posts: 11,814
Likes: 5,120
From: SW Ohio
https://www.hastingsmfg.com/ServiceT...reignition.htm
I didn't dig too deep into the subject for fear that the OP's original question would be hijacked. I changed my original post so it wasn't ambivalent.
Last edited by Campy Roadie; Jul 9, 2014 at 04:41 AM.
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Seasoned HDF Member
Joined: Sep 2009
Posts: 25,306
Likes: 2,443
From: Eastern NE
If you're super-low on fuel...use it. Otherwise, while out riding, look for fill station w/Premo somewhere down the road. I sometimes like to plan a stop at a few local fill stations carrying 95 octane...find them & plan accordingly.
