Nice 91 octane Ride

[BLACK WIDOW]

91 octane

Pretty accurate analogy.

Our Spyders run a compression ratio that is too high for regular. This isn't theory, this is fact.

Sure BRP says you can run regular and the Spyder does fine on regular. No one is disputing this. But how is it that both are true?

There can be only 1 answer. BRP has modified other factors which reduce performance and allow for octane lower than our compression ratio requires.

Can we get some performance back by raising Octane? This is where the debate is because only BRP knows how this game is being played.

I found this on a High Performance Engine web page.

KNOCK-SENSOR-EQUIPPED VEHICLES
Automakers began using knock sensors in the late 1970's. When knock occurs it sends a signal to the main computer, which retards the spark timing until detonation ceases. The best thing about a knock-sensor is its ability to reduce or eliminate engine damage due to detonation. It can, however, cause spark-timing retard, which reduces horsepower and fuel economy. Using a gasoline high enough in octane to satisfy the engine under all types of conditions will ensure maximum performance.

Here is a Minimum Octane vs. Compression Ratio chart. With a compression ratio of 10.8:1 and no modifications for knock our Spyder would require 100 Octane, minimum.

So, all things being equal, even premium fuel won't get us where our compression ratio requires us to be. Even with premium we still need an anti-knock system because 92/93 is not enough.

The question is, will higher octane get our ECM to give us a more advanced spark timing, thus improved efficiency, power and mileage?

BRP could tell us for sure, but we can also experiment. That is what I have done.

Good informantion--This pretty much parallels my thinking.

 

[gazey]

Come on guys...Just fill em up and ride :doorag: :joke:

 

[Roaddog2]

Come on guys...Just fill em up and ride :doorag: :joke:

:agree::agree:

 

[BLACK WIDOW]

91 octane

:agree::agree:

:agree:with 91 octane:joke: Or anything else you feel comfortable withnojoke

 

[Smylinacha]

93 octane ryder:2thumbs:

 

[krb1945]

Octane .vs. detergents in fuel

Cylinder cleaning agents have been all but eliminated in all gasoline. These agents keep most of the soot and carbon lumps from forming in the cylinders. If carbon does form in the cylinders then it glows like embers and ignites the fuel as it is entering the cylinder, ie. surging and sputtering.

You can help with this problem by using valvetech carbon guard in your gas. Initially start with 1 oz per five to six gallons. After a couple of tanks the cylinders and heads will be cleaned up then you can reduce it to about .6 of an oz per five gallons.

I found this out the hardway... a 13,000 dollar boat engine destroyed because of carbon causing spitting and sputtering.

Many thanks to the "tree huggers" for forcing the gasoline industry remove the very chemical that makes all gasoline engines run better and run cleaner. Folks... they, "the tree huggers" ain't got it right yet. We use to have lead fumes which is harmful but now the exhaust we breathe when sitting at a redlight turns into sulphuric acid when mixed with moisture. So how can that be the answer? It is according to them. By the way remember you have lots of moisture in your throat, nose and mouth.

 

[baldev]

"and higher octane gas sits around longer because it doesn't sell as well as regular"

Only if someone orders the same amount of premium. Usually I ordered only about 1500 gals of premium every "other" day compared to 7500 of reg and mid. Therefore premium did not sit around any longer than necessary.

I see no diff using either 87 or 93.

 

[BLACK WIDOW]

Fuel

"
I see no diff using either 87 or 93.

I've heard stories that at some establishments there isn't.:dontknow:But you know that one can hear almost anything.nojoke

Michael:doorag:

 

[Firefly]

While I'm pretty sure you're not going to damage the rotax by running higher octane--- I've read that running it in some engines can actually cause damage.

I'll try a weeks worth of it this week--- and maybe I'll be joining the 'high octane' club --- but I'm not holding my breath (always a skeptic).

 

[BLACK WIDOW]

91 octane

While I'm pretty sure you're not going to damage the rotax by running higher octane--- I've read that running it in some engines can actually cause damage.

I'll try a weeks worth of it this week--- and maybe I'll be joining the 'high octane' club --- but I'm not holding my breath (always a skeptic).

Try to find some that does not contain Ethanol and I think you'll feel the difference.nojoke


Michael:doorag:

 

[BajaRon]

Try to find some that does not contain Ethanol and I think you'll feel the difference.nojoke


Michael:doorag:

That is a pretty good trick these days. Ethanol costs us about 10% in fuel mileage. Not sure what that power loss is but I suspect about the same.

Sure good to know the tree huggers are looking out for our best interests here.....Right?

 

[bone crusher]

I think gas stations in MD use 10% ethanol.

Regardless, I haven't had a problem with my Spyder and octane level. I've run all three octanes and never really felt a difference. No point in paying extra money for no gains.

Widow, if your bike only runs well on premium, there might be another problem as the bike shouldn't need higher octane to run normally.

This is an interesting situation you have...as far as ethanol goes, I don't like the stuff!

 

[BLACK WIDOW]

91 octane

I think gas stations in MD use 10% ethanol.

Regardless, I haven't had a problem with my Spyder and octane level. I've run all three octanes and never really felt a difference. No point in paying extra money for no gains.

Widow, if your bike only runs well on premium, there might be another problem as the bike shouldn't need higher octane to run normally.

This is an interesting situation you have...as far as ethanol goes, I don't like the stuff!

Didn't mean to imply that my spyder doesn't run ok on 86 octane, it just runs a whole lot better on 91. It runs enough better that I will certainly pay the difference in the price. We can still get real gasoline ( no alcohol) here in Oklahoma so that is what I use and I will continue as long as it's available.nojoke

Michael:doorag:

 

[prodrag69]

that also depends on what you got done to your spyder.... my spyder detonates with 87 i hafe to run 93 or add octane buster to make up the diff. :chat:

 

[BajaRon]

that also depends on what you got done to your spyder.... my spyder detonates with 87 i hafe to run 93 or add octane buster to make up the diff. :chat:

What have you done that makes it not run on regular fuel?

 

[prodrag69]

I got the duel two brothers exhaust and the juice box with the race air intake and some other small tricks..... im taking to afew people in regards to custom cams for the spyders and Aerocharger 2.0 Turbocharger by HiPerformance about tourbo charging a spyder:yes: theres just alot of B.S. that we hafe to work on first:spyder:

 

[Firefly]

I think the individual mods are a good thing to look at pertaining to octane use. I filled up with 93 today--- and will run a few weeks on it to see if I notice any difference. Since my sputtering was intermittent - it's hard to tell what the fix will be. Not sure if I've had as much sputtering since I pulled the evap can. Going to keep an eye on it.

Just gonna keep an eye on it....

 

[prodrag69]

what do you have done to your spyder firefly

 

[3wheeldemon]

... I filled up with 93 today--- and will run a few weeks on it to see if I notice any difference...

:chat: We converted the last of the Mohicans!!!


3WD

 

[Firefly]

:chat: We converted the last of the Mohicans!!!


3WD

Nooooooo---- not converted --- just willing to put it to the test...... don't mind being proven wrong at all---- it's bound to happen SOMETIME-:roflblack:
__________

I'm running: Evoluzione Race air intake system with custom airbox and two cold air intake vents, Fuel pressure mod @ 63 psi, O2 Mod and hindle pipe.