87 Octane A.K.A., Unleaded Regular
Cruiser
Joined: Feb 2014
Posts: 168
Likes: 6
From: Parker, CO
My tank holds 6 gallons, price difference between regular unleaded and premium will say is 30 cents. 6 x 30 = $1.80. Price of my new Harley $20,700. I will spend the extra $1.80 everytime I fill up.
Seasoned HDF Member
Joined: Jul 2007
Posts: 6,336
Likes: 67
From: SW Minnesota
The '09 TC96 engines, which watchguy has (based on his sig pic), has a compression of 9.2:1 . TC88's have 8.9:1. It wasn't until 2012 that the compression went to 9.6:1 on the 103 engine. 2014's have 9.7:1, with the twincooleds at 10:1.
Road Master
Joined: Mar 2013
Posts: 1,151
Likes: 14
From: Seattle
A couple of weeks ago I put in a tank of non-ethanol 87 and my bike didn't like it...started pinging. Next tank I went with 92 non-ethanol and the pinging was reduced but not gone. 3rd tank with 92 and I'm back to no pinging. Maybe that first tank was bad? I think I'll keep some octane boost with me from now on, but I'll stay away from the 87 if I can.
Road Warrior
Joined: Sep 2013
Posts: 1,926
Likes: 193
From: ohio
Neighbor accidently put 87 in his 12 limited, said it pinged horribly, scared the .... out of him, his bike is stock, but like stated above, maybe $1.80 a tank savings not really worth the risk. I can tell the difference in different gas stations , popping on decel ect.
Oh, goodie! A fuel thread! Seriously, Bikerlaw has it nailed...the other things to be aware of is one fillup of fuel means nothing...need to do it for a while...the first fillup contains a lot of the fuel that was in there.
I am in the habit of filling with 91 octane higher zoot fuel whenever I have the choice...Chevron with Techron is my first choice then Shell, Mobil, Unocal, and everything else after that...I'll run some Sea Foam thru, and some Startron, just for ducks...but if your bike runs good on the cheap stuff, yeah, do it, I'm not so certain that I, and everybody else running expensive stuff thru our bikes, aren't throwing our money away...
For me, I get peace of mind out of it, just like changing my synthetic oil every three thousand miles. The scientists will tell you that's a waste of money, time, and effort...but then again, I'm not a scientist...
I am in the habit of filling with 91 octane higher zoot fuel whenever I have the choice...Chevron with Techron is my first choice then Shell, Mobil, Unocal, and everything else after that...I'll run some Sea Foam thru, and some Startron, just for ducks...but if your bike runs good on the cheap stuff, yeah, do it, I'm not so certain that I, and everybody else running expensive stuff thru our bikes, aren't throwing our money away...
For me, I get peace of mind out of it, just like changing my synthetic oil every three thousand miles. The scientists will tell you that's a waste of money, time, and effort...but then again, I'm not a scientist...
Grand HDF Member
Joined: Aug 2014
Posts: 4,726
Likes: 1,787
From: Toledo ohio
Look at it from this prospective. One of the guys posted the benefits of the detergent in premium fuel. Good point. Figure this. 5 gallon tank,, 10 cents more per gallon. 50 cents is cheap insurance for detergents and higher octane.
Stellar HDF Member
Joined: Jun 2007
Posts: 2,178
Likes: 600
From: SoCal.....I'm only here for the weather
I run the best gas I can. If I can't find premium I will run mid-grade. A fill-up of 5 gallons will only yield a difference of 50 Cents or so. Why even consider this when gas prices will vary day to day. What you paid for premium yesterday is what you will pay for regular today. If you're gonna' sweat a 50 cent difference on a 200 mile tankful then you probably have bigger problems to think about.
Just my .02.
Just my .02.
Cruiser
Joined: Aug 2014
Posts: 199
Likes: 0
From: California
Just about to say the same thing...91 for me.
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Stellar HDF Member
Joined: Dec 2009
Posts: 2,035
Likes: 8
From: Western Canada
you're right
09 T.C's are in fact 9.2-1 not 8.5 as I said.
Seasoned HDF Member
Joined: Aug 2011
Posts: 11,814
Likes: 5,120
From: SW Ohio
Let's see all those "I run 87 octane in my bike and there's no difference!" posts. That way when you try and sell your bike here, everybody will have a heads up
It's not just compression ratio that warrants the use of 91 or better, cylinder/head temps (higher on air cooled engines) and ignition timing. Can you get away with it? Sure, for a while. Colder ambient temps do reduce one element of the equation, but not all. Running low octane fuel in hot weather is asking for it. I know, I know; you live on the border in Yuma and it's 130 degrees F at 0600 hours and you've never run anything but 87 octane cut with water 50/50. Never had the first problem and the bike 380,000 miles on it. I call bullshit; that or you're deaf. I've ridden a Harley all over this continent and have had to use low octane fuel because there wasn't anything else (the Rockies, Mexico, Canada and northern Alaska). There is a difference.
A couple of guys have hit it on the head with some very good points, but here's the best one. A guy spends good money for a Harley, presumably he did a little research and found that it requires premium fuel; then he bought it. Now, after the deal is consummated he wants run fuel that isn't recommended but "lowers operating costs" because he saw a post on the internet from a guy who knows a guy who's 1st cousin is a bigwig petrochemical engineer at an oil company that he can't name. Anyway, this guy says that gasoline is gasoline and they're just selling you the same stuff no matter what grade you buy.
Run what you want in your machines. I buy and sell used bikes and one of the FIRST things I look for is signs of false economy legacies; that includes internet forum posts.
It's not just compression ratio that warrants the use of 91 or better, cylinder/head temps (higher on air cooled engines) and ignition timing. Can you get away with it? Sure, for a while. Colder ambient temps do reduce one element of the equation, but not all. Running low octane fuel in hot weather is asking for it. I know, I know; you live on the border in Yuma and it's 130 degrees F at 0600 hours and you've never run anything but 87 octane cut with water 50/50. Never had the first problem and the bike 380,000 miles on it. I call bullshit; that or you're deaf. I've ridden a Harley all over this continent and have had to use low octane fuel because there wasn't anything else (the Rockies, Mexico, Canada and northern Alaska). There is a difference.
A couple of guys have hit it on the head with some very good points, but here's the best one. A guy spends good money for a Harley, presumably he did a little research and found that it requires premium fuel; then he bought it. Now, after the deal is consummated he wants run fuel that isn't recommended but "lowers operating costs" because he saw a post on the internet from a guy who knows a guy who's 1st cousin is a bigwig petrochemical engineer at an oil company that he can't name. Anyway, this guy says that gasoline is gasoline and they're just selling you the same stuff no matter what grade you buy.
Run what you want in your machines. I buy and sell used bikes and one of the FIRST things I look for is signs of false economy legacies; that includes internet forum posts.