Regular vs. Premium

OK so the great debate. Regular gas vs premium gas. Im running a two bros exhaust and the bike runs like crap on regular and a champ on premium. kid i know with a 2011 ninja 650r says that you dont need to run premium its just a waste of money. he has a yoshi pipe on his.

second note, should he run a PC on his bike or no? He says he doesnt have to and my local indy shop says otherwise. I need one for my bike regardless because I have rpm issues and he blames the pipe and no PC. Thanks!

 

Dunno about anyone else, but I've never put drop one of premium in my '99 and have had no issues at all. It does have the PC III, but I don't think that is a factor.

 

I'VE ALWAYS LET MY EAR AND WRIST DECIDE whether or not I'm gonna run premium fuel in any given engine.



My ST will loft the front tire on WOT in first gear on 87 octane, first and second at WOT on 93 octane and first second and occasionally third on 90 octane no ethanol gas.


I here detonation when using 87 octane in my pickup truck so I run midgrade in it and it runs fine.


My wifes van doesnt seem to care what you put in it, it runs fine so she uses regular.


All of my lawn equipment get the no-ethanol gas reguardless.


Run 2 tanks of each and let the bike decide. the rings and pistons you save will be your own!


.25 price difference x 6 gallons usual fillup is only 2 dollars 50 cents. Is an undetonating motor worth that???? I think so.

 

My '99 runs great on Regular...love it! Preignition/pinging/detonation is the damaging issue octane mitigates. If your bike runs poorly on regular, run premium.

 

Run what you want.

Without answering you question, here's a bunch of unsolicited babble. lol

If your bike is going to sit for any length of time, or if it takes you longer than 2 weeks to go through a tank of gas, you should certainly consider running a higher octane. Fuel will actually start to lose its octane rating in as little as 2 weeks. Absolutely use a fuel stabilizer if you have to do winter storage.

(If I was as lucky as Concours and could find a station around here that was ethanol free, I'd fill everything I could with it. You're a lucky man to have that).

Premium burns more efficiently, therefore it runs hotter.

No name brand gas is the exact same gas as the name brand. The difference is what type and how many additives, detergents, etc. are added. In simple terms, Sunoco, Shell, Mobil, Joe's Gas & Go all pull up to the same refinery and get the same gas. But then they move to the next station and that's where the additive is put it. Shell may have some proprietary formula, as does Mobil. But Joe's Gas & Go does not. So your 93 Octane from Joe's may not actually burn as clean and thoroughly as your 93 from Shell.

Untreated fuel (especially ethanol) will wreak havoc on your system. I fucking hate ethanol.

 

l had a looong discussion about this on another forum after l did some testing using different octane rated fuels and we all sort of come to the conclusion that unless your bike has been tuned to run on high octane fuel, just stick to the regular 91/95 oct stuff, with 98 octane l had less mpg, also the end of the pipe started sooting up with no extra power or easier starting (if anything the reverse happened) my bike is a Gen 5 and l'm in Aus, but l think the same would apply anywhere:vtr2:

 

I am not sure if the same thing is happening outside Europe - but over here, national taxation rules mean that oil companies are incentivised to use at least 5% bio-Ethanol in petrol. As the EU is good at growing stuff - producing wine lakes and grain and butter mountains in the past, I can understand this tax break as it reduces our dependence on imported oil from OPEC, and stops the farmers overproducing stuff we don't really need.

What worries me most is that, at least in the EU, that to make higher octane petrol (equivalent to your super), they put more bio-ethanol into the fuel. Obviously as the sensors in the stock 800 VFRs were devised well before these eco fuels appeared, I rather doubt they are clever enough to detect or ever make use of any "enhanced energy content" within the higher octane fuel. So on a stock bike you are probably wasting money using it. Perhaps if you have a an aftermarket tuning kit and paid someone to preform a dynamic remap you might benefit.

But each to their own - its your money to spend as you like - I prefer to spend mine riding my VFR rather than subsidising Exxon...!

I have no idea whether or not the sensors on the more recent 1200's are able to detect and really make use of the higher octane - but doubtless someone on here will be be able to advise.

Why worry about ethanol in fuel? - Well yes it burns OK, but unlike fuel produced exclusively from mineral oil, over time it has a tendency to attack rubber - so not good for VFR fuel lines and indeed the filler cap seal. Hence I go for standard fuel with the least amount of ethanol I can find.



Skimad4x4
Proud member - 6th Gen Militia # 218 - European 1st Division

 

I used to use the special premium high octane fuel with fuel system cleansers until I bought a user manual and read it. My 5th gen doesn't need it! When I changed to regular unleaded, I got better mileage instantly, and I was paying less for it. If your engine isn't tuned to use premium, then there really isn't a point in using it.

 

Yes, read the owner's manual and it will tell you what gas to use.

 

Ethanol sucks. We can all agree to that.

However, the myths about regular versus premium continue to persist.

The ONLY difference between the two (and besides the obvious numerical octane rating) is that the higher the octane rating, the more resistant the fuel is to pre-ignition (which is where heat and compression ignite the fuel vapors BEFORE the piston reaches TDC instead of the spark plug igniting the mixture). Pre-ignition, detonation, pinging are all the same thing, and are really bad for your con-rod and crankshaft bearings.

Premium does not "burn more efficiently". It does not increase fuel economy. Use regular grade fuel in any vehicle that does not specify needing a higher octane gas. My 4G gets nothing but 87, and runs like a top. I used to put premium in it, and the only difference was the $1.00 more it cost on every fill up.

If your vehicle says that it will use regular, and has pinging issues, something else is likely wrong with it - stuck rings, excessive cylinder wall or bearing wear, low oil, bad mods, etc. Running an otherwise fine running machine on premium is a waste.

 

How many miles on your bike? Have you ever changed the spark plugs? The manual calls for 87 octane. I have a Yoshi pipe and can tell no difference in regular and premium other than my wallet!!

 

I probably chose the wrong word. Agreed, it does not burn more efficiently as in better gas mileage.

Maybe a better description is that it burns more thoroughly. (?) Completely?

 

You would have to retard your ignition timing to account for the slower burn of a higher octane gasoline to take full advantage of the fuel you are using.
That is the only way you would get a higher octane gas to burn more efficiently, if you don't do that you are wasting your money if the manual calls for 87 octane.

 

The manual for my 98 says it is ethanol 10% safe and to use 91 Octane or higher.
I mean, for 99% of cars, 87 is fine. They are tuned for Joe average and Joe doesn't want to pay for expensive gas.
For bikes, what is an extra 80 cents or dollar for a fill up? Is the 5th gen factory tuned for 87 and Honda says to use 91 just because? Maybe. Bear in mind also for the carb crowd, bikes are jetted lean from the factory and with ethanol gas are running even leaner.

 

Not necesarily....



The ST1300 specifies 91 octane or better because of the compression ratio's. Generally the high the comp ratio of the motor the higher the octane fuel that is needed for it to run without detonation. Honda is showing 10.8 to one for this motor.


Throw in alittle wear and tear, alittle summer heat and you've got a thin fuel mix running thru the motor.


ping ping ping.


The truck I run the mid grade in is almost worn slap out as she has well over 200k on driveline but I havent made a truck payment in 4 years so I'm gonna run her as long as I can. I think that motor might be in need of a couple of cans of Sea Foam as she doesnt like to Idle much....Carbon deposits will also cause detonation.....


My Point is this, If your heads were assembled from the factory with any protruding metal parts (valve seats or burs) this protruding little part will act like a glow plug. I've seen large block Chevy heads where the vavle seat stuck out 1/16th of an inch from the surface of the head. Since its a new motor with a new warranty its unlikely that the owners gonna want to do a top end over haul because of alittle pinging but those little protruding metal parts start action like a glow plug at about 2500 rpm. THIS is why I say let the motor decide what octane it wants. I'm not likely to pull a head on a motor that likes mid grade....I dont know many that will either.


The cost of alittle more octane to me trump's the coming engine damage. Wanna see what all the pinging is doing to your motor, Google image search "detonation" and look at some of the pictures.....Its ugly!


I can see the need for saving money on just about everything else on a motor vehicle except 3 things.....I always let the engine decide what fuel it wants, I always buy factory replacement brake parts ( on my bike its kinda necessary the St's like to bind on aftermarket pads) and I never buy cheap tires. "Go they may, stop they must and we prefer they go in the direction of OUR choosing!"

 

I forgot about carbon deposits causing pinging - this is also a primary culprit.

Essentially, anything that reduces the volume of the combustion chamber will marginally increase your compression ratio from the original specification. I would guess that's the case with your old truck - seafoaming the hell out of it would probably help quite a bit.

To go off on a tangent for a different perspective: Detonation is also a big problem to deal with in turbocharged and supercharged cars. My car is turbo'ed and requires 91 octane from the start, even though the motor has 8:1 compression. The pressurized turbo charge makes up for this low compression ratio and likely pushes the "real" compression ratio into the 11-13:1 range. I have turned up the boost on the car, and it now requires 93 octane to resist pre-ignition. When it was stock, I tried to run it on 89, and it pinged and knocked like crazy. The 91 requirement was certainly needed. Most modern FI cars have knock sensors that will detect pinging in the motor and retard timing (and kill power output) when knocking is detected.

@ Pliskin: I'm still not following you 100% on the efficient/completely/thoroughly burn of 87 octane vs. 91/93 octane. Gasoline will burn as completely/thoroughly as the combustion process and specific engine allows, regardless of the octane rating of the fuel in the tank. All other things being equal, you're not gaining any sort of efficiency by changing the octane of the fuel. Like I stated in my post, the higher the octane, the more resistant the gas is to setting itself ablaze as a result of compression. If I am following your comment correctly, the inverse argument would actually be true - i.e. a higher octane fuel would actually be less likely to burn completely/thoroughly because of it's resistance to self-ignition.

This is why diesel engines (that run on compression/self-ignition alone) have "octane" ratings in the 15-30 range. I put "octane" in quotes, because the actual rating used for diesel is cetane, which is slightly different than octane ratings.

For anyone still not understanding octane readings, this Wiki article will be very handy:
Octane rating - Wikipedia, the free encyclopedia

 

Looks like Honda changed the octane rating in 2000 when they changed the fuel injection and did away with the auto enrichener....

 

What makes you say that? They added the O2 sensors, but I've never come across anything to say that the 2000+ bikes need a different octane rating than the <=1999 bikes. Are you confusing octane rating with oxygen sensors? I'm not being a smart-arse... I simply don't understand how you've come to the info you've shared (ie: if there's good info, that you have, it would be good to hear about it, but I suspect that there's some confusion)...

 

Hi Danny_TB,
Y2Kviffer said his 2000 owners manual calls for 97 octane.
Dirk said his 1998 owners manual calls for 91 octane or better.

Which is why Y2Kviffer made the comment you are referring to.

 

Thanks for letting me know. I must've missed those details (oops, my bad). I have a '97 (well, model year '98, but built in '97 - very very early VFR800 {before they reached 300 production bikes} based on the VIN/build date), so 91 RON fuel works fine for mine. If the Y2K+ manual says to use higher octane, then that's fair enough: there must've been tuning changes other than adding the O2 sensor, and the fuel that Honda specifies is the fuel that should be used.