Octane article. Should I use 91?

[WiVR]

This comes from a servicers website and I don't know if it has been posted before, but what are your thoughts? I have been using 91 in my 84VR and am wondering if it's necessary. The whole article does not seem to post well so here's the link:

 

 

 

http://www.motorcycleperf.com/techtips/gasoline.htm

[Squidley]

It was explained to me that running higher octane is not worth it. 87 octane actually burns hotter than 91, the higher octane is for engines over 11 to 1 compression, the Ventures are 10 to 1.

 

I run 87 in all my bikes and NEVER have any problems with it....I wouldn't waste your money on it.

[Yammer Dan]

What Squid said.

[bongobobny]

As long as you are not geting any spark knock, and are happy with the slightly less fuel economy and performance, then you will probably be OK. The biggie is the spark knock, or predetonation. If you are getting the explosion before your piston is up to TDC, you can, and will, have detrimental effects on your engine. The choice is yours, for myself I use high test...

 

If you read the sticker on the inside of the engine cover, the 1200cc requires 91 octane.

[Freebird]

I agree with Dan agreeing with Squid.... or something like that.

 

I run 87 octane and have never had a problem of any kind.

[E-Fishin-C]

You guys!!!,,It like this.... you are saying Beer is Beer and its not, Its High Octane all the way for me.... And a Good Premium Beer :rotf:

[TxVenture]

agree with MR. E-FISHIN-C totally. Also, if you are at 11.0 to 1 compression, you better be using something better than pump gas even 91 or 93 octane, probably 118 octane!!!

 

Don H.

[mm482]

In this case cheaper is better. I have run 87 to 93 octane and I get just as good mileage with the 87. I have tried this with my 86 VR and 00 RSV.

 

Earl

[Black Owl]

If you read the sticker on the inside of the engine cover, the 1200cc requires 91 octane.

 

I may be wrong (I usually am). But, I suspect that a closer reading of that label with show that the fuel grade is regular or research grade 91 RON.

 

Different countries have some variation in what RON (Research Octane Number) is standard for gasoline, or petrol. In the UK, ordinary regular unleaded petrol is 91 RON (not commonly available), premium unleaded petrol is always 95 RON, and super unleaded is usually 97-98 RON. However both Shell and BP produce fuel at 102 RON for cars with hi-performance engines.

 

In the US, octane ratings in fuels can vary between 86-87 AKI (91-92 RON) for regular, through 89-90 (94-95) for mid-grade (European Premium), up to 90-94 (RON 95-99) for premium unleaded or E10 (Super in Europe)

 

If yours shows something different, maybe you could post a pic of it.

[bongobobny]

In this case cheaper is better. I have run 87 to 93 octane and I get just as good mileage with the 87. I have tried this with my 86 VR and 00 RSV.

 

Earl

 

The '86 VR is a different engine. Owl, you may be right on that; I'll go out to the garage and check, however, I agree (somewhat) with TX Venture in that 10:1 compression is a little beyond 87 octane without knock sensors to retard your timing...

[Redneck]

I run mid grade I get some spark knock with some regular brands. Altitude comes into play as well the lower you go the more octane you will need to keep the spark knock at bay. The best way to figure out what your bike needs is to run different grades and check mileage and performance. the spark knock in mine is very noticeable on take off just as the clutch fully engages and loads the engine.

[bongobobny]

OK Wise Old Owl, you are right, sort of. It indeed does state minimum Research Octane 91, however it also says Grade: Regular LEADED! You remember the old leaded gas, don't you?? Lead was added to fuel as an antiknock compound. So, getting back to my original statement, "As long as you are not getting any spark knock..." Mine rattled under load going uphill on middle premium but did not with premium. And yes, my timing is just about exactly on 5 degrees BTDC.

[Scooter]

My '83 seems happier and gets better mileage with 91.

[Leadwolf56]

I've tried regular, mid-grade and premiumin my 90 VR. It runs the best and gets the best mileage with the premium. If I want it to run really well I add a can of Seafoam to it (it LIKES it).

[1 - UP]

I get better response from my bike ('04) with the higher grade. When I used the '87 I got a ping. Don't use it anymore! I burned the higher grade with my '88 and it did real well.

 

Ken

[Condor]

I donno, I run premium because in my mind it runs cooler due to better burning. The difference in price is not an issue when taking on 3-4 gallons, and I figure it's not going to hurt the motor running it, so why not....

[ediddy]

A friend of mine with an 04rsv couldn't believe I used 87 octane so I started using 91 in my 05rsv. I can't tell any difference so I went back to 87octane.

[Snarley Bill]

heres the straight scoop on high octane fuel.this is from dyno results on a friend of mines engine that was using aircraft fuel.if you have preignition problems due to high compression or other things ,such as excess carbon or a hot spot in the combustion chamber. you definately need a higher octane fuel to prevent detonation and slow down the burning rate of the fuel.if you have no preignition problems you will actually.lose horse power and engine effiency do to the slower burn rate of the fuel.his engine had no preignition problems and he made more horse power with unleaded regular then with aircraft fuel on the dyno.there is nothing in high octane fuel to make it produce more power.the only difference is the additive which was once lead, that is added to slow down the burn rate,to prevent preignition and engine damage.bill