Anyone tried 87 octane in a Harley?

[Errtt]

Was thumbing in one of my Harley shop manuals and it states to use 87 or higher octane pump fuel. I always use premium. Probably not a good idea with a bike with some mods.
Just wondering if anyone uses 87 in their Harley.

 

[tommygunn]

Most of those bikes have pretty big, thumpy, high-displacement engines, usually compression related engine knock is the last thing I'd expect to be an issue.

Depending on the mods, short of advancing any timing that is, I'd probably say on any gas the thing should run fine, but I have no real experience with it.

A sport bike with high compression is something I'd be more concerned about feeding regular.

 

[ddrumman2004]

I run 87 octane in my 2000 Sportster 1200 I just took possession of. If it was to "ping" from low octane fuel, I would never hear it.
It runs great...I just wish I could get non-ethanol fuel for it...and my mowers, atvs.....etc...

 

[GT Mike]

The Sportster 1200s were ok for regular grade till 2004 when the compression was bumped to 9.5:1. I'm not certain about what the Big Twins ran for stock compression ratios. Since H-D engines have a rather large combustion chamber, fuel with too high of octane might actually reduce performance due to flame travel or lack thereof.
My buddy was running premium in his '99 XL1200C and on my advice he tried lower octanes. No difference in performance, and no pinging. Only difference is on a hot restart, it would sometimes backfire (older Sportys had dual-fire ignition) out the exhaust. Sometimes embarrassingly loud too. Only once in a great while would it do it on higher octane fuels.

If you're worried about running lower octane, try dropping it little by little and pay attention to how it performs. At 1/2 tank, fill it with midgrade for a final octane of 90 (assuming 91 octane premium), then next time you're at half a tank, fill it with 87 for a final octane of 88.5, etc. If you're to the point where you're running straight 87 with no pinging, stick with it. No sense blowing more money than you have to out the tailpipe, even though we're only talking at worst case about $1.50 difference per 5 gallon fill-up compared to premium grade.

 

[car54]

I noticed I could make my 2005 sportster 1200 ping with low octane while under high load, but only in the hottest of weather. unless I was idling for half an hour in traffic and then took off down the highway in 100F ambient, it wouldnt ping. I ran regular gas almost all the time.. if I was worried, I would go with mid grade. Then I got tired of the clunky gearbox, horrible handling and super heavy weight of the bike and sold it. best decision ever.

 

[Robenstein]

Originally Posted By: car54
I noticed I could make my 2005 sportster 1200 ping with low octane while under high load, but only in the hottest of weather. unless I was idling for half an hour in traffic and then took off down the highway in 100F ambient, it wouldnt ping. I ran regular gas almost all the time.. if I was worried, I would go with mid grade. Then I got tired of the clunky gearbox, horrible handling and super heavy weight of the bike and sold it. best decision ever.


A sportster is heavy ? I guess thats subjective but it only weighs about 50lbs more than a Bandit 1200 of the same year but an awful lot less than most fullsize cruisers.

 

[Errtt]

Well I got down to about a half tank last night and decided to top-off with 87 octane.
Got a little ping now and then when conditions were right. Guess I'll stick to premium.
Had to try it.

 

[cycleman]

Originally Posted By: Errtt
Well I got down to about a half tank last night and decided to top-off with 87 octane.
Got a little ping now and then when conditions were right. Guess I'll stick to premium.
Had to try it.


I always run premium in my 08 Heritage. That's what the manufacture calls for, so see no reason to change.

 

[car54]

Originally Posted By: Robenstein

A sportster is heavy ? I guess thats subjective but it only weighs about 50lbs more than a Bandit 1200 of the same year but an awful lot less than most fullsize cruisers.


My main bike is an sv650. Ive owned everything from a virago 250 to a hayabusa.. and the Harley sportster, while a fun bike just didn't handle like I expected. the biggest problem I ran into was the 12 miles of concrete roadway on my way to work, every expansion joint sent a jolt up my spine that hurt like mad. no other bike is as harsh.

 

[GT Mike]

car54, Your 2005 Sportster was required to run 91 octane minimum. It's no surprise you got pinging with lower octane.

 

[car54]

I know. My point was, it worked ok on 87 except in the toughest of circumstances.

 

[BigCahuna]

My '96 ex-cop bike had a sticker on the left lower leg that stated to use 87 octane gas, or higher in it. I'm pretty sure the PD that owned it before me used only regular in it. That's all I put in it, and it seemed to run fine. The only time I heard it ping was if I was riding in slow moving traffic for 10 minutes or more, then tried to accelerate hard. By me the difference between regular and high test is about 40 cents a gallon. That's $2 a tank' times however many tank fulls you run in a year. It starts to add up when you look at it. So if regular works fine, why run high test?.,,

 

[GT Mike]

Originally Posted By: car54
I know. My point was, it worked ok on 87 except in the toughest of circumstances.
My '06 was a bit more finicky about its fuel. I'd get pings on anything but the best quality 91 octane non-ethanol gasoline. I did have some mods (pipes, air cleaner, carb re-jet) that may or may not have changed its octane demands. Also, 2006 was the year they ran the Buell heads, which delivered 9.75:1 compression ratio.
This sort of made them the year of the freaks, since it was the only year that they were carbureted with the better flowing heads (and different cam grind). The '07 and later EFI versions were sluggish by comparison, probably due to the very lean map they were programmed with from the factory.
On the dyno, I was about 10 HP/15 ft. lbs. torque over what's considered stock RWHP. The dyno operator was quite impressed when he saw my numbers vs. my mod list, which was nothing but simple bolt-ons and a little carb tweaking.

 

[Errtt]

^ interesting as my 97 Sport has buell heads, shaved flywheel etc.
Top it off with a re-worked SE carb, re-worked intake, have it re-cam'd, SE pipes etc. etc.
Guess I'll have to stick to premium and just have fun with it.

 

[GT Mike]

You'd have to determine your compression ratio to make sure, but based on your mods, I wouldn't run anything less than premium just to be safe. My '06 liked a little race gas (Citgo 110 octane leaded) when it was really hot out. Ran much smoother under load compared to pump gas. Not to mention the strange looks when you leave Bike Night on a little Sporty and it smells like a drag car. Keeps 'em guessing.

 

[dja4260]

My 97 1200 sporty pings with anything less then 92 octane. I typically add a few cups of 114 octane race gas. It runs much better with it. It isn't stock however.

 

[kballowe]

My 2008 Fat Boy likes the 93 octane stuff. Intermittent ping on 91 octane.

Took the '09 Street Bob from St. Louis out and up thru Montana and into Idaho. Mostly two-lane roads with the only thing available - 87 octane. No ping. Got back to civilization and filled with 93 and there was a definite power improvement on the 93 stuff. I was surprised that it ran that well on 87.

 

[RatBikeRandy]

2000 FXD SuperGlide, carbureted.
The 91 octane is recommended - not required so I had to try the cheaper stuff. Runs fine on 87 unless I'm loaded down and under more load like mountain roads. It'll ping some then, so I run premium on those occasions.

 

[budrow79]

I've ran 87 every fill up in mine since it was new. It's a 2003 FLSTC. No problems in 45,000 miles.

I used 85 octane a couple times when I was down in the southen states on trips. It ran fine too.

 

[whip]

I almost always ran 87 in both of my Sportsters. Never had a problem.