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Interesting Fuel Stats.


Grum

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Hi All.

For many years I've logged a large number of  fuel runs on an XL Spreadsheet going back to my 2004, 2007 RWB, 2009 and my current 2014 8gen. The interesting thing here is I only ever ran the 2004 and 2007 on Premium Unleaded either 95 or 98ron, the 2009 was a mix between Premium and Standard 91ron. My 8gen has only ever been fed on Standard Unleaded 91ron, which is what the bike is designed for anyway.

 

2004 - Averaged 5.29 Litres per 100k's (Premium Unleaded Only)

2007 - Averaged 5.25 Litres per 100k's (Premium Unleaded Only)

2009 - Averaged 5.06 Litres per 100k's (Premium and Standard Fuel)

And the Winner Is...........:cheerleader:

2014 8gen  - Averaging only 4.32 Litres per 100k's (Standard Unleaded 91ron Only)

 

(All of the averages are based on many tank cycles and none are city riding, virtually all my riding is country, long distance and with a fair amount of twisties thrown in.)

 

Just goes to show what a big improvement Honda has made to the 8gen fuel economy AND Using Premium Fuels is a waste of money. (I'm not entering an argument as to whether Premium Fuels offer better cleaning agents OR not!)

 

Merry Christmas and Happy New Year to all our readers, Safe riding for 2018 AND remember - Stay upright, but if you can't, then go lay down with someone nice!:blush:

 

Cheers.

Grum :beer:

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Ya know, Could be we ride harder when we're younger....  just saying.....  Cheers!

 

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17 minutes ago, Pjcliffo said:

Yes it does show a great improvement in fuel economy which could be due to many different advances and changes but it shows nothing about premium fuel as you have not used it in gen 8. Cheers

 

Ah Peter you caught me out!!!! :blush:.

 To be completely honest I have done a couple of tanks of Premium through the 8gen just to prove the fact it achieves nothing as far as economy is concerned. The VFR's do not have an anti knock sensor so they cannot automatically advance the ignition timing to take advantage of the higher octane thus improving performance. Nothing is achieved by blowing extra bucks on Premium fuel for a VFR.

Cheers and hope ya still loving that Arrow Exhaust.

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10 minutes ago, Pjcliffo said:

Yep still loving it, worth every cent. What fuel consumption did you get on the premium?

 

Ok, here's a couple for you - 309k's on 98ron got 4.77ltr/100k, 424k's on 95ron got 4.32ltr/100k. However my best economy and this involved a mixture of hilly and flat roads was 407k's got 3.94ltr/100k using Standard 91ron. Even my 2009 which I would occasionally run Premium fuel on never showed any economy improvement over the 91ron.

Cheers.

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3 minutes ago, Pjcliffo said:

I thought my street triple with arrows sounded great but the vfr is a different but very beautiful song.

Excellent.

Cheers.

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Thanks for the stats Grum.  To what do you attribute your 8th gen's better fuel efficiency?  Also, is your standard octane in Australia 91?  Or do you guys have a different rating system?  Here in Florida it's usually only 87 as you can see in the pic below.  I usually fill up with the 93 V-Power.

 

img_1230-jpg.39399

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MY experience is that VFR's run terrible on premium fuel and great on regular fuel, especially regular fuel without welfare ethanol in it.  My 8th gen. does get significantly better fuel mileage then either the 5th or 6th gens., under the same riding conditions, that I've owned and the 8th gen. runs better, especially at lower rpm's.  Some have said the top end speed is slightly lower but I'll never know as I have no need to go that fast.  

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43 minutes ago, GatorGreg said:

Thanks for the stats Grum.  To what do you attribute your 8th gen's better fuel efficiency?  Also, is your standard octane in Australia 91?  Or do you guys have a different rating system?  Here in Florida it's usually only 87 as you can see in the pic below.  I usually fill up with the 93 V-Power.

 

img_1230-jpg.39399

The United States uses a different octane measurement. Our 87 octane ((R+M)/2 ) is equal to 91 RON in Australia and New Zealand. So his regular gas is our regular gas. 

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10 hours ago, GatorGreg said:

Thanks for the stats Grum.  To what do you attribute your 8th gen's better fuel efficiency?  Also, is your standard octane in Australia 91?  Or do you guys have a different rating system?  Here in Florida it's usually only 87 as you can see in the pic below.  I usually fill up with the 93 V-Power.

Hi Greg.

There's a lot of changes to the 8gen to help fuel economy, lighter weight, lighter electrical loads (LED headlights), different cams, different throttle bodies and no doubt some re tweaking of the EFI system.

 

Our Standard Unleaded Fuel is 91ron which I believe is equivalent to your 87aki (anti knock index) fuel. Just as economist above stated.

Our Shell V-Power is Premium 98ron, (the most expensive!) which equals your 93 rating.

 

So the bottom line here is you're probably burning holes in your wallet by using the 93 V-Power when your 87 or 88 would be fine in the VFR. - Check your American Owners Manual and see what the recommended minimum Octane fuel is.

 

I am amazed by the number of VFR owners I've met in Australia that are convinced they need to run their VFR's on Premium Fuels, for all sorts of interesting reasons - Ahh yes, the power of advertising!!! When I purchased my first VFR in 2004 the dealership said to run it on Premium, didn't think twice back then, I'm a fair bit older and a little wiser now! 

 

Cheers. 

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4 hours ago, Grum said:

Hi Greg.

There's a lot of changes to the 8gen to help fuel economy, lighter weight, lighter electrical loads (LED headlights), different cams, different throttle bodies and no doubt some re tweaking of the EFI system.

 

Our Standard Unleaded Fuel is 91ron which I believe is equivalent to your 87aki (anti knock index) fuel. Just as economist above stated.

Our Shell V-Power is Premium 98ron, (the most expensive!) which equals your 93 rating.

 

So the bottom line here Greg is you're probably burning holes in your wallet by using the 93 V-Power when your 87 or 88 would be fine in the VFR. - Check your American Owners Manual and see what the recommended minimum Octane fuel is.

 

I am amazed by the number of VFR owners I've met in Australia that are convinced they need to run their VFR's on Premium Fuels, for all sorts of interesting reasons - Ahh yes, the power of advertising!!!

 

Cheers. 

 

My owner's manual recommends "86 or higher".  It also says "Use recommended octane number.  Using lower octane gasoline will result in decreased engine performance."  I'm skeptical as to whether or not the 8th gen's engine, with its 11.8:1 compression ratio, would really deliver optimum performance with only the minimum recommendation of 86 octane.  If the manual says using lower octane (85 presumably) will result in decreased engine performance, doesn't it stand to reason that using 91 or 93 octane would result in increased engine performance?   The manual does recommend "86 or higher", not 86.

 

I was curious so I did some quick research into what minimum octane is recommended for some other Hondas, here's a list below with their respective compression ratios and minimum recommended octane.  I wonder why all those engines except the 8th gen recommend a minimum of 91 octane - what is so special about the 8th gen's engine that it won't derive some benefit from the higher octane?  Maybe someone can do a dyno run with their 8th gen using both 86 and 93 octane fuels and post up the results.

 

CBR 1000RR 12.3:1  91

CBR600RR  12.2:1 91

7th gen VFR1200 12.0:1 91

8th gen VFR800 11.8:1  86

S2000  11.1:1 91

 

 

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28 minutes ago, GatorGreg said:

My owner's manual recommends "86 or higher".  It also says "Use recommended octane number.  Using lower octane gasoline will result in decreased engine performance."  I'm skeptical as to whether or not the 8th gen's engine, with its 11.8:1 compression ratio, would really deliver optimum performance with only the minimum recommendation of 86 octane.  If the manual says using lower octane (85 presumably) will result in decreased engine performance, doesn't it stand to reason that using 91 or 93 octane would result in increased engine performance?   The manual does recommend "86 or higher", not 86.

 

Hi Greg.

My manual states 91ron or higher, so you should be fine using your 87. There is virtually NO difference in the calorific value (energy content) between Standard and Premium octane fuels. The advantage is with high performance engines that DO have anti knock sensors the ignition timing can be advanced further without the potential of knocking or pinging (detonation) so this creates  better power or effectively better economy. HOWEVER the VFR's as already stated don't have anti knock sensors so they can't take any advantage of the higher octane fuel, that's why there's no benefit.

The manual statement of 86 or higher simply means the higher you go you get a greater safety margin for pinging knock (detonation). Going lower than the recommended octane is not recommended as this would likely induce detonation a nasty pinging sound, this definetly decreases combustion efficiency and if really bad do serious engine damage.Try your bike on the 87 octane I'm sure you won't have an issue. Ask some of your VFR friends see what they reckon.

You are contradicting yourself a bit by stating "The manual does recommend 86 or higher,  not 86"  You could say 86 is recommended but not any lower!

 

Cheers

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US uses an average of the MON and RON for their rating which is why the number is lower for the exact same fuel.

 

Because of the 8 to 12 octane number difference between RON and MON noted above, the AKI shown in Canada and the United States is 4 to 6 octane numbers lower than elsewhere in the world for the same fuel. 

 

https://en.wikipedia.org/wiki/Octane_rating#Anti-Knock_Index_(AKI)_or_(R+M)/2

 

As for anything less than 5.5L/100km consistently... all I can think is that must be babying it a lot more than me!

 

651405.png

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13 hours ago, Bent said:

MY experience is that VFR's run terrible on premium fuel and great on regular fuel, especially regular fuel without welfare ethanol in it.  My 8th gen. does get significantly better fuel mileage then either the 5th or 6th gens., under the same riding conditions, that I've owned and the 8th gen. runs better, especially at lower rpm's.  Some have said the top end speed is slightly lower but I'll never know as I have no need to go that fast.  

 

In my experience, my 4th gen didn't care at all what fuel I put in there, including crap grade tractor gas once while I was stuck way out in the middle of nowhere.  But my 8th gen seems to be much more discriminating.  At hooligan RPMs most folks probably would never notice but cheap gas grades really hurt low RPM performance.  It was a difference I could both hear and feel.

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+1   with one exception....

 

I once pulled over at a gas station in Germany, running on fumes...

Close to Luxemburg, the home of cheap gas,  on offer was E85, so I thought is was 85 octane...

(we normally have 95, 98, 102 octane)

 

Euuuhh no.

 

it was 85% ethanol  

which I found out soon enough, stuttering and spluttering..... :491:

 

 

So no, RC36's donot enjoy ALL fuels....

 

 

:goofy:

 

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12 hours ago, Grum said:

You are contradicting yourself a bit by stating "The manual does recommend 86 or higher,  not 86"  You could say 86 is recommended but not any lower!

 

Haha, yeah my point is that they don't just say the "recommended octane is 86, period - end of discussion".  They say "86 or higher".  Therefore, I tend to read it as "recommended octane is greater than or equal to 86, with 86 being the absolute bare minimum to achieve acceptable engine performance" :tongue:

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7 hours ago, GatorGreg said:

 

Haha, yeah my point is that they don't just say the "recommended octane is 86, period - end of discussion".  They say "86 or higher".  Therefore, I tend to read it as "recommended octane is greater than or equal to 86, with 86 being the absolute bare minimum to achieve acceptable engine performance" :tongue:

 

So what's ya plan Gator? Are you going to give a good quality reputable brand 87 octane a go in your bike or not?

 

The same can be said for all the millions of cars out there designed for standard fuel. Petroleum companies would love you to believe their higher octane Premium Fuel will perform miracles for you, they make more bucks from the Premium fuels.!!!!!

Performance will not be increased on a VFR by Higher than needed octane fuels

Cheers.

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I ran 87 octane exclusively this year after re-read my owners manual and noticed that 87 is all it needs. I haven’t experienced any degradation of performance or any pre-detonation at any RPM. 

 

Last year, after I made the switch from 93 to 87 octane, I kept track of my fuel mileage and it was unchanged.

 

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2 hours ago, economist said:

I ran 87 octane exclusively this year after re-read my owners manual and noticed that 87 is all it needs. I haven’t experienced any degradation of performance or any pre-detonation at any RPM. 

 

Last year, after I made the switch from 93 to 87 octane, I kept track of my fuel mileage and it was unchanged.

 

 

There you go GatorGreg. Exactly as expected, stop wasting your money. That's how the Economist's make their money! Smart purchasing :wacko:

 

Cheers.

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On 11 December 2017 at 3:29 PM, adprom said:

As for anything less than 5.5L/100km consistently... all I can think is that must be babying it a lot more than me!

Hi adprom.

Most likely the difference is that, all my riding is country stuff, no stop/start city riding at all.

I do admit that at the ripe old age of 61 my testosterone levels are probably much lower than yours, but there are specific roads I know where the fun police normally don't frequent where I do tend to stretch the throttle cable a little!

I'm don't consider myself to be a slow rider, then again I'm not fast, it's a bit of know when to hold em, know when to fold em if you know what I mean.

On a side issue has Honda sorted out those Maintenance discrepancies for the 2017 owners manual you hi-lighted some time back? Perhaps you could update that thread, it carries a lot of interest.

Cheers

Grum. 

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OK, so the issue here it that there is NO SUCH THING as Premium fuel. Fuel comes in various octane ratings & there are generally 2 used in the world just to confuse people. MON in the American influenced world & RON in the rest of the world. MON87 roughly equates to RON95. The higher the number the more the fuel when mixed in the correct AFR resists detonation, this is normally linked to compression ratio, and as a general rule the higher the compression ratio the higher the octane rated fuel required.  BUT

 

The BUT being most manufacturers confusingly state the engines static compression ratio, this is if you set the piston to BDC, then closed the valves & forced the piston to TDC. But as we all know, valves are never closed except at ignition time. So what you really need to know is the DYNAMIC compression ratio & for most well tuned engines designed to run on normal octane fuel (MON87-RON95) that will be around 10.5-10.9-1 ratio. Even the CBR1000RR & various other 1000cc sports bike quoting 12+ or 13-1 ratios only manage 10.x dynamic compression due to valve overlap to allow maximum rpm's to carry power higher up the speed range.

 

The upshot of this is that "premium" or rather higher octane fuels can NOT produce more power or better mpg, the energy content of a set volume of fuel is fixed, so regardless which you inject the amount of power out is more a factor of the AFR than the fuel octane. In theory if our cylinders were working perfectly at the ideal 14-1 AFR then they would burn 0.0000273cc per cylinder per cycle. MPG or MPH is a determined to a large extent by the engine speed, acceleration & riding style plus load applied to the vehicle. So a bike travelling at a constant speed below 50mph will have significantly better mpg than one reaching 100mph & back to 30mph randomly on a track, mostly due to revs and speed of acceleration.  You can run your own numbers, but efficiency is a combination of power required & where any engine sits in the rev range relative to the road speed required. So a big engine at idle can often be more efficient than a mid sized engine below/above peak torque rpm, where as a small engine running at peak torque rpm will often be more efficient than either of the others, but then you won't have much speed or power in reserve.

 

On my euro tours, I often got 200miles from 17L of fuel or 53mpg, at motorway speeds commuting to work I can't get 170miles from 19L, or 40mpg (UK gallon=4.546L), on a track day I can push that close to 30mpg, due to running in low gears at high rpm all the time. So run some numbers for a VFR at say 5000rpm constant & 11000rpm constant & you will find that whilst fuel flow at higher rpm is reduced due to cylinder filling time reduction, the amount of fuel applied is only slightly less, depends on the volumetric efficiency of the engine in each rev range..

 

 

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