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Octane levels

Justscootin

Jeff Wilson life member
When your motorcycle calls for 89 octane and you run 87 what are the problems with that? During the winter I put fuel stabilizer in my gas and that kills the octane so in the spring when I run the engine for the first tank octane is probably at a very minimum.

In a car the computer system adjusts itself to the octane level so you do not have the ping sound you had in an engine of the 1970's.

Does the computer system in the bike adjust for the octane we have in the gas in our bike tanks?
 
The engine computer can adjust to a point. What that is I don't know. How do you know the fuel stabilizer kills the octane? Keep in mind too, that higher octane is really meant to minimize/eliminate potential pinging issues. Lower octane fuel actually "burns" faster than higher octane fuel.

I have done this for 18 years with my 94 RS: at the end of the season I fill the tank with non-ethanol fuel. No fuel stabilizer, never used it. I do add Techron to the fuel. Park the bike in my unheated garage and plug in the Battery Tender. Duct tape over the intake and exhaust, and let it sleep for the 3-1/2 months I won't be riding it. If I just changed the oil late in the season it stays in.

Come spring, I'm ready to go. Never had a problem. Bike still has the original fuel pump, fuel regulator, injectors (never taken out for cleaning).
 
Duct tape over the intake and exhaust,

That is sort of funny as I put my Z3 away every year and one year I had to put it in a storage locker as I was between houses. Sure enough I had a mouse build a house in the air box.

As for fuel stabilizer and storing the bike I have always put fuel stabilizer in my bike tanks and cars. I have heard the octane does deteriorate (or evaporate). As for the octane level I would guess if it is low there should be no real concern.
 
another "orifice" nemesis is mud daubers as they love! any hole about 1/4-3/8" dia.. this includes MC's & is a warm month event.
 
Does the computer system in the bike adjust for the octane we have in the gas in our bike tanks?

AFAIK the modern boxers do have the sensors and the mapping to adjust somewhat for potential pre-ignition, however the F series (esp. twins) do not (not sure about the multis, but would assume they have the more sophisticated engine mgmt systems). The Fs can be re-mapped to take lower octane fuel but that requires a trip to the dealer.

OTOH, I am not aware that octane suffers any significant loss over the short-term periods we're talking about (i.e. 3-6 months). The use of fuel stabilizer may be beneficial, but I have had no problems in the winter shut-downs (both cold and warm storage) in which I have not used it.

Of course, long term storage (i.e. > 1 year) dictates a different set of storage protocols, which includes purging all fuel from the machine, including tanks, lines, throttle bodies, etc.

JP
 
The octane figures you see on pumps are directly related to the altitude of their location. So, for example, 87 at high altitude is pretty much equivalent to 89 at a lower altitude. Your owners manual recommendations don't account for this and probably list sea level recommendations.
 
OTOH, I am not aware that octane suffers any significant loss over the short-term periods we're talking about (i.e. 3-6 months).

actually, fuel starts to degrade in a matter of weeks, let alone months. if i had 3-6 month old untreated fuel in my bike, i'd seriously consider putting it into a car, where the larger tank capacity can allow it to be diluted with fresher fuel.
i'd say you've been lucky in the past.
 
When your motorcycle calls for 89 octane and you run 87 what are the problems with that? During the winter I put fuel stabilizer in my gas and that kills the octane so in the spring when I run the engine for the first tank octane is probably at a very minimum.

In a car the computer system adjusts itself to the octane level so you do not have the ping sound you had in an engine of the 1970's.

Does the computer system in the bike adjust for the octane we have in the gas in our bike tanks?

quite a few variables here- primary one being... what bike are we talking about? a 2012 R1200, a 1978 R100, or something inbetween?

bottom line- run the lowest octane fuel that your bike will tolerate without pinging under load. using anything else (higher octane) is wasting money, and providing absolutely no benefit to your bike.
hi temps, low rpms, heavy weight all make pinging (pre-detonation) more likely.
 
ANDYVH,

you have the original fuel pump, injectors, etc?! Makes me feel good about the longevity of my bike.
 
Yeah, and my 94 RS has "only" 170,000 miles on it. So I'm pretty convinced that Techron is an excellant regular additive, about twice a season at least. The othe factor is to ride regularly. I do about 10,000 miles per year, so the bike gets ridden reguarly.

Been rock reliable since day one at 3,000 miles when I bought it. All my own maintenace too, only been in the shop twice for warranty work.
 
I only have about 36,000 on mine, but she is ridden regularly. I use Techron once in a while. I am a mechanical zero, but I am good about taking her in for her scheduled and annual service. I know there are no guarantees, but I feel good about her...especially after reading your post.
 
actually, fuel starts to degrade in a matter of weeks, let alone months. if i had 3-6 month old untreated fuel in my bike, i'd seriously consider putting it into a car, where the larger tank capacity can allow it to be diluted with fresher fuel.
i'd say you've been lucky in the past.

It's easy to do, even for folks like me who shouldn't own a screwdriver...

I've been doing this for a few years now.
 
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