Honda CB500X

Main CB500X Boards => Maintenance and Servicing => Topic started by: war2112 on February 17, 2019, 03:23:50 AM

Title: Recommended octane for 2013 CB500X
Post by: war2112 on February 17, 2019, 03:23:50 AM
Hello all,

New owner here of a 2013 model. I apologize if I don't see this topic posted before, but any advice on octane. The owner's manual recommends 86 minimum. I am wondering if regular is ok (87 octane in my state). I will by all means spring for the mid-grade or premium but maybe that is not the right path to go too high.

What is the sweet spot in in terms of octane rating?

I am a newbie so thanks for your input!

Wes
Title: Re: Recommended octane for 2013 CB500X
Post by: uku383 on February 17, 2019, 04:01:01 AM
87 should be fine. Higher octane numbers simply mean that the fuel is more resistant to pre-ignition from combustion pressure (different engines have different compression ratios - higher performance engines typically have greater compression, requiring higher octane fuels.). A higher number than stated in your manual will not be harmful, but a lower number risks pre-ignition and engine 'knock'.

Some people occasionally fill up with a tank of especially high grade fuel, simply because these more expensive fuels often have additional detergents added that can help with cleaning out your engine, but it's not strictly necessary.

Hope that helps.  :002:
Title: Re: Recommended octane for 2013 CB500X
Post by: Mister Paul on February 17, 2019, 11:26:06 AM
They're designed for standard fuel. The Internet is awash with people arguing the benefits of spending more on the fancy stuff, but it's not worth it.
Title: Re: Recommended octane for 2013 CB500X
Post by: war2112 on February 17, 2019, 03:05:03 PM
Hey guys,

Thanks very much for the advice! That's kind of what I expected. There is a reason why one should read the owner's manual and if that is what is recommended then good deal. Appreciate your real world input.
Title: Re: Recommended octane for 2013 CB500X
Post by: ThirtyOne on February 17, 2019, 07:00:17 PM
*Originally Posted by war2112 [+]
Hey guys,

Thanks very much for the advice! That's kind of what I expected. There is a reason why one should read the owner's manual and if that is what is recommended then good deal. Appreciate your real world input.

Yep. Just follow the manual...except for tire pressure recommendations. I think they say 42psi rear. I run my rear in the 36-38 range. 42 yields a very bumpy ride. It might help with tire longevity, but I'm wiling to trade some mileage for a significantly more comfortable ride.

(let the tire pressure debate commence  :008:)
Title: Re: Recommended octane for 2013 CB500X
Post by: war2112 on February 17, 2019, 11:07:32 PM
*Originally Posted by ThirtyOne [+]
Yep. Just follow the manual...except for tire pressure recommendations. I think they say 42psi rear. I run my rear in the 36-38 range. 42 yields a very bumpy ride. It might help with tire longevity, but I'm wiling to trade some mileage for a significantly more comfortable ride.

(let the tire pressure debate commence  :008:)


Thanks for the advice on tire pressure , ThirtyOne. I will be checking mine and adjusting as necessary.
Title: Re: Recommended octane for 2013 CB500X
Post by: uku383 on February 17, 2019, 11:49:27 PM
*Originally Posted by ThirtyOne [+]
Yep. Just follow the manual...except for tire pressure recommendations. I think they say 42psi rear. I run my rear in the 36-38 range. 42 yields a very bumpy ride. It might help with tire longevity, but I'm wiling to trade some mileage for a significantly more comfortable ride.

(let the tire pressure debate commence  :008:)

Yeah, but the suspension is so soft... I think that I have a cast-iron arse, 'cause I don't notice it, running 42... besides, isn't 42 the answer to life, the universe and everything? (groan - dad joke alert)  :008: :008:
Title: Re: Recommended octane for 2013 CB500X
Post by: ThirtyOne on February 18, 2019, 12:14:14 AM
*Originally Posted by war2112 [+]

Thanks for the advice on tire pressure , ThirtyOne. I will be checking mine and adjusting as necessary.

Sure thing. It's good to get into the habit of checking it regularly. Could be a warning if you have a slow leak because you've picked up something pointy that could cause a blowout. Handling changes dramatically with the right tire pressure as well.
Title: Re: Recommended octane for 2013 CB500X
Post by: EscCtrl on February 18, 2019, 12:49:37 AM
*Originally Posted by war2112 [+]
Hello all,

New owner here of a 2013 model. I apologize if I don't see this topic posted before, but any advice on octane. The owner's manual recommends 86 minimum. I am wondering if regular is ok (87 octane in my state). I will by all means spring for the mid-grade or premium but maybe that is not the right path to go too high.

What is the sweet spot in in terms of octane rating?

I am a newbie so thanks for your input!

Wes

I use 89, 90,or 91 which is midgrade in my area. The 87 and 88 in our area seem to have more than the max 10% ethanol. No need for 92 or 93 premium. It's overkill and a waste of money. I got my best fuel mileage on 87 nonethanol fuel, 72mpg calculated.
Title: Re: Recommended octane for 2013 CB500X
Post by: Lysdexic on February 18, 2019, 09:54:03 AM
Fuel here in Thailand seems to have a lot of ethanol, mine runs best on straight gasoline. Here that means high octane too.
Title: Re: Recommended octane for 2013 CB500X
Post by: Ron V on February 18, 2019, 03:20:14 PM
I ran mine on 89 for the first few years, now I have been running 87 more often.  If I had to guess, I'd say they sell less of the 89 and therefore it's likely older when you buy it and the 87 is always fresh.  So who knows how much difference there even is.  Owner's manual says it's fine and the computer makes up for everything anyway.  Lower octane actually makes more horsepower all other things being equal. 

I've run 85 octane as well, when I was at a station that had nothing else in the high altitude regions.
Title: Re: Recommended octane for 2013 CB500X
Post by: CodeSlow on February 18, 2019, 04:59:39 PM
Owner's Manual I have recommends Research Octane Number (RON) 91 or higher.  Here in the States, the octane rating shown on the pumps is the average of RON and Motor Octane Number (MON) shown as (R+M)/2.  The (R+M)/2 can be seen on the octane sticker at the pumps.  MON can be anywhere from 8 to 12 octane numbers lower than RON.

So, with a recommendation of 91 RON in the manual, that comes out to anywhere from 85 octane (on the pump sticker) to 87 octane or higher.
Title: Re: Recommended octane for 2013 CB500X
Post by: Hillie on February 18, 2019, 06:14:16 PM
I prefer US premium (91) and, if possible, ethanol free. It's a little more expensive, but worth it to me. My truck runs nicer with ethanol free and the bike sounds a little better too. Could be imagination, but I buy (fake?) peace of mind for a few bucks, so I think it's a good trade-off. :)
Title: Re: Recommended octane for 2013 CB500X
Post by: war2112 on February 18, 2019, 11:13:07 PM
*Originally Posted by uku383 [+]
Yeah, but the suspension is so soft... I think that I have a cast-iron arse, 'cause I don't notice it, running 42... besides, isn't 42 the answer to life, the universe and everything? (groan - dad joke alert)  :008: :008:

Hah, love it and I get the Dad joke! I am of that age. Hitchhiker's Guide to the Galaxy and also referenced in the X-Files being that Mulder's apt number was 42.

Good stuff!
Title: Re: Recommended octane for 2013 CB500X
Post by: war2112 on February 18, 2019, 11:17:55 PM
Thanks for all the input everybody. I notice a theme which is to definitely watch out for the ethanol content.
Title: Re: Recommended octane for 2013 CB500X
Post by: Hillie on February 20, 2019, 08:37:40 AM
Yes. I prefer ethanol free for all my vehicles. Sure, the manual says that up to 10% Ethanol is OK, but in my experience the ethanol-free stuff has been better.
Title: Re: Recommended octane for 2013 CB500X
Post by: CodeSlow on February 20, 2019, 03:34:11 PM
A difference between non-ethanol gasoline and ethanol gasoline is the energy (BTUs) they have.  A gallon of non-ethanol gasoline will have higher energy than a gallon of ethanol gasoline.

Ethanol has around 76K BTUs and gasoline has around 114K BTUs.
Therefore, in theory, pure gasoline should yield better economy than a blend of gasoline and ethanol. However mixtures of about 10% ethanol have around 112K BTUs so the difference in fuel economy might be negligible. 

Ethanol also has a higher oxygen content, which leads to lower emissions, less carbon deposits, etc. and the higher octane of ethanol allows gasoline of lower octane (possibly lower cost) to be blended with ethanol to produce the same final octane rating at the pump. 

I personally cannot tell the difference between the two fuels tank to tank, but if you feel it makes a difference then more power to you.  Use what works best for your bike, region, and your riding style.
Title: Re: Recommended octane for 2013 CB500X
Post by: SnowOwl on February 20, 2019, 04:31:22 PM
 :460:
Title: Re: Recommended octane for 2013 CB500X
Post by: Jonathan on February 20, 2019, 11:13:01 PM
*Originally Posted by CodeSlow [+]
A difference between non-ethanol gasoline and ethanol gasoline is the energy (BTUs) they have.  A gallon of non-ethanol gasoline will have higher energy than a gallon of ethanol gasoline.

Ethanol has around 76K BTUs and gasoline has around 114K BTUs.
Therefore, in theory, pure gasoline should yield better economy than a blend of gasoline and ethanol. However mixtures of about 10% ethanol have around 112K BTUs so the difference in fuel economy might be negligible. 

Ethanol also has a higher oxygen content, which leads to lower emissions, less carbon deposits, etc. and the higher octane of ethanol allows gasoline of lower octane (possibly lower cost) to be blended with ethanol to produce the same final octane rating at the pump. 

I personally cannot tell the difference between the two fuels tank to tank, but if you feel it makes a difference then more power to you.  Use what works best for your bike, region, and your riding style.

the big issue with ethanol is it's hygroscopic...a while back I fitted a fuel filter/water separater on my old VW aircooled. Amazing how much water it collected. Mind you, the bus didn't run for months at a time and I rarely topped off the tank, so it's hardly surprising...
Title: Re: Recommended octane for 2013 CB500X
Post by: EscCtrl on February 21, 2019, 12:48:10 AM
*Originally Posted by Jonathan [+]
the big issue with ethanol is it's hygroscopic...a while back I fitted a fuel filter/water separater on my old VW aircooled. Amazing how much water it collected. Mind you, the bus didn't run for months at a time and I rarely topped off the tank, so it's hardly surprising...

 :169:  :460:
Title: Re: Recommended octane for 2013 CB500X
Post by: andystracey on February 27, 2019, 12:48:22 PM
Very few, if any, motorcycle engines have a knock sensor detecting the exact firing time and adjusting the ignition accordingly. Most cars have this feature meaning using different octane fuel can affect the engines timing and ultimately its performance. As most bike engines have a fixed egnition time the fuel octane level is irrelevant and you are simply wasting your money buying high octane fuel. Note, ethanol content is an entirely different subject that I donít really understand but thanks to other comments on this thread I now know a great deal more.