What kind of fuel? - Harley Davidson Street Forum - Street 500 and 750
User Tag List

 10Likes
Reply
 
LinkBack Thread Tools
post #1 of 37 Old 07-08-2014, 04:37 PM Thread Starter
Junior Member
 
Join Date: Jul 2014
Location: Granger, IN, USA
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
(Thread Starter)
What kind of fuel?

I'm getting conflicting information as to what kind of gas to put in my new Street 750.

The dealer told me to always put in premium, however the manual states "87 (91 RON)" which would be standard gasoline. The HD website however says "Recommended 91 octane or higher fuel (R+M)/2." (See Street 750 | Liquid-Cooled | Harley-Davidson USA )

So what is the appropriate fuel for my new Street 750?
Sherri likes this.
DonM is offline  
Sponsored Links
Advertisement
 
post #2 of 37 Old 07-08-2014, 05:02 PM
Senior Member
 
Livin On's Avatar
 
Join Date: Nov 2013
Posts: 548
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 226 Post(s)
Either or. Recommended just meand optimal performance but you wont get the pings. You'll be fine with 87 don't worry. Now many do run 91 just because its a smaller tank, better MPG's. Its up to you...
Livin On is offline  
post #3 of 37 Old 07-08-2014, 09:08 PM
Senior Member
 
Street500owner2's Avatar
 
Join Date: Jul 2014
Location: Chicago Illinois
Posts: 204
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 82 Post(s)
Quote:
Originally Posted by DonM View Post
I'm getting conflicting information as to what kind of gas to put in my new Street 750.

The dealer told me to always put in premium, however the manual states "87 (91 RON)" which would be standard gasoline. The HD website however says "Recommended 91 octane or higher fuel (R+M)/2." (See Street 750 | Liquid-Cooled | Harley-Davidson USA )

So what is the appropriate fuel for my new Street 750?
That's a good question, when I was at the dealer I told them I only burn premium gas in all my motorcycles. In fact I only burn premium gas in my lawnmower, weed whips and leaf blowers too. Most premiums here (Chicago land) have additives in them to help clean fuel injectors which the streets are fuel injected. So therefore, I'll stick with the premium gas and pay the few extra cents more.
Street500owner2 is offline  
 
post #4 of 37 Old 07-08-2014, 10:04 PM
Senior Member
 
gears's Avatar
 
Join Date: Apr 2014
Location: NW Indiana
Posts: 121
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 66 Post(s)
The 750 is 10:1 compression, and the 500 is 11:1 compression.
I suggest the highest octane available.
Sherri and wke002 like this.
gears is offline  
post #5 of 37 Old 07-08-2014, 10:23 PM
Super Moderator
 
bbally's Avatar
 
Join Date: Apr 2014
Location: Grand Junction, Colorado
Posts: 485
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 177 Post(s)
The octane debate.

Premium does not really mean anything better.

Octane is representative of the level at which the gasoline will ignite under pressure with no spark. Commonly called pre-ignition. No octane level is better than any other from a gasoline quality standard. So octane has to do with the engine compression and the altitude you live and drive at. I run 87 in all 4 of my bikes. Vrod to the buell.

I live at 5000 asl so no chance of pre-ignition with that octane here.

The 750 at sea level will not pre-ignite with 87.

Won't hurt anything but your wallet to run 91 but in many cases it is not necessary.

Just don't use 91 because it is said to be premium. It is actually worse than lower octane since they add alcohol to change the ignition pressure.
Livin On and SWDan like this.

USMC '79-'85 Sgt.
1st Mar Div, 1st FSSG Det A in the Stumps
Malo periculosam, libertatem quam quietam servitutem
PGR Rider



2016 FLTRXS
2015 XG 750
2003 VRSCA

1982 GS1100GK
bbally is offline  
post #6 of 37 Old 07-09-2014, 05:32 AM
Senior Member
 
Street500owner2's Avatar
 
Join Date: Jul 2014
Location: Chicago Illinois
Posts: 204
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 82 Post(s)
Quote:
Originally Posted by bbally View Post
The octane debate.

Premium does not really mean anything better.

Octane is representative of the level at which the gasoline will ignite under pressure with no spark. Commonly called pre-ignition. No octane level is better than any other from a gasoline quality standard. So octane has to do with the engine compression and the altitude you live and drive at. I run 87 in all 4 of my bikes. Vrod to the buell.

I live at 5000 asl so no chance of pre-ignition with that octane here.

The 750 at sea level will not pre-ignite with 87.

"Won't hurt anything"but your wallet to run 91 but in many cases it is not necessary.

Just don't use 91 because it is said to be premium. It is actually worse than lower octane since they add alcohol to change the ignition pressure.
A very good point that you bring up, but companies like Mercedes-Benz recommends that you only burn premium in their automobiles if you do not, you void the warranty on the engine. In fact, right in the instruction manual it will say if you have to put anything except premium in the car only put as much gas in the car to get you to the next gas station to fill up with premium only.

With that said, there must be something premium does that the other two octanes don't do, that Mercedes-Benz feels that you will destroyed their engines if you don't use it, It voids out the warranty! Food for thought.
Street500owner2 is offline  
post #7 of 37 Old 07-09-2014, 08:40 AM
Super Moderator
 
bbally's Avatar
 
Join Date: Apr 2014
Location: Grand Junction, Colorado
Posts: 485
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 177 Post(s)
Quote:
Originally Posted by Street500owner2 View Post
A very good point that you bring up, but companies like Mercedes-Benz recommends that you only burn premium in their automobiles if you do not, you void the warranty on the engine. In fact, right in the instruction manual it will say if you have to put anything except premium in the car only put as much gas in the car to get you to the next gas station to fill up with premium only.



With that said, there must be something premium does that the other two octanes don't do, that Mercedes-Benz feels that you will destroyed their engines if you don't use it, It voids out the warranty! Food for thought.

Pre-ignition pressure is important. And high performance high compression require it.

But the label premium is just to get people to think it is better or more powerful. Neither of which it true.

USMC '79-'85 Sgt.
1st Mar Div, 1st FSSG Det A in the Stumps
Malo periculosam, libertatem quam quietam servitutem
PGR Rider



2016 FLTRXS
2015 XG 750
2003 VRSCA

1982 GS1100GK
bbally is offline  
post #8 of 37 Old 07-09-2014, 09:14 AM
Senior Member
 
Join Date: Dec 2013
Location: Too far north
Posts: 261
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 144 Post(s)
Garage
Both my Sporty and my Street Rod supposedly require minimum 91 octane according to the manual. There is about $.35+ difference here between 87 and 91. However, the other benefit of running 91 is that where I buy gas, 91 is non-ethanol, whereas the 87 and 89 are 10% ethanol. Now I don't know if there would be any negative effects of running ethanol gas in my bikes, but it does wreak havoc in small engine equipment such as mowers, chain saws, etc.. Cars made these days do not seem to be affected if driven daily, but my old classics are another story since they are stored over the winter. Ethanol gas and long term storage do not complement one another for sure.

Enough rambling... if it were me, I would use 91, preferrably non-ethanol if available.
stude is offline  
post #9 of 37 Old 07-09-2014, 10:11 AM
Senior Member
 
Street500owner2's Avatar
 
Join Date: Jul 2014
Location: Chicago Illinois
Posts: 204
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 82 Post(s)
As per the HD Owner's Manual....for years....it has stated to use a minimum Octane Rating of at least 91. This is due to HD using a med/hi compression ratio and that the engine is air cooled, the higher Octane Rating will decrease pinging, also, especially critical on the newer fuel injected bikes like the Street 500 & 750, Premium Gasoline contains additives that lower grade gasoline doesn't have that help keep the injectors and fuel filter clean.

The information listed above is from one of Harley Davison’s mechanical engineers that I talked to. So, for the extra $1.40 more for a tank of gas in the Street: Is it really worth to cheap out? Stay with what is recommended by the manufacturer and you’ll be safe.

Last edited by Street500owner2; 07-09-2014 at 10:47 AM.
Street500owner2 is offline  
post #10 of 37 Old 07-09-2014, 11:04 AM Thread Starter
Junior Member
 
Join Date: Jul 2014
Location: Granger, IN, USA
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
(Thread Starter)
I wouldn't say I'm trying to cheap out, I just want to make sure I'm buying the correct octane for the bike. In theory, using higher octane that recommended is actually causing your engine to produce less power and use more gas.

My car requires 91 octane by the manufacture. The problem is the conflicting information given by Harley. The manual given with my bike states 87 octane, the website 91 octane, and the dealer 91 octane. If it really is 91 octane they should update the US manual.

For now I've just been using 91. The bike has been running fine and just hit 175 miles (Not bad for a week of ownership.) I'm glad to hear that a HD mechanical engineer recommends 91, it puts my mind at ease.

Last edited by DonM; 07-09-2014 at 03:09 PM. Reason: typo
DonM is offline  
Reply

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Forum Replies Last Post
Street fuel mileage stude Harley-Davidson Street General Discussion 34 12-26-2015 11:26 PM
Report your fuel mileage stude Harley-Davidson Street General Discussion 33 08-28-2014 08:32 AM
Transparnet Fuel Tank Mod Looks Awesome Yusef Street Appearance & Modifications 5 04-16-2014 11:54 AM

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome