Ive always read  the debates about this and was wondering specifically on the GSs what grade of fuel you guys run, and if you notice MPG/performance changes depending on such. 

You didn't include 93.I run 93 because our shitty station dumps left over  E85 in the 87 and dumps 87 in the 89.Plus I seem to pick up water from those tanks.None of my vehicles will run on the stations 87 or 89,so I run the 93.I have always had problems running Shell gas in any thing I have.Even my mowers won't run it.This is the only close station to me.That's why I frequently stop there.Lately I've been shopping around in the areas I travel.

Didnt include 93 cuz its not availible in Cali lol. 

Mainly just trying to figure out if people run the cheapie 87 or the most expensive "premium"

The midgrade is a straight mix of the higher and lower. 

21 views and 3 votes?

WTF Vote! 

I run 93 because I have a V&H ignition advancer, and because under the seat, on the emissions sticker, it says to run min 91RON.  Ibelieve this is a different formula we use at the US pumps (RON+MON/2 I believe) so I err on the side of higher octane.

I have only put 2 tanks of gas through her so far, so maybe I'll try out the 87 or 89 and see what happens.  More than likely....nothing.   

Im filling up almost every day (yes I ride alot ) and was thinking I could save a few bucks a day with 87.  Maybe Ill try it when Im just commuting and not going on a performance ride. 

I have been using 87 without any problems. It gets me 54 mpg(so no complaints). I did try the other ones with no noticeable effects and hence stuck with this.

I was under the understanding that the GS engine wasn't high enough compression to worry about upgrading to higher octane fuel.  I run 87 with no problems--getting 60 MPG if I'm conservative with the throttle, and not much less if I'm not. 

right. the octane number is the gas' resistance to detonation ( a bad thing)

it's a low compresion engine..

and i read that alot of airclood engines dont take well to 91

as they heat up fast and then have to cool down fast...

it's supposed to warp it more then 87....

maybe if i got ping/knocks i would run higher...

for now i'll save my 25 cents per fill up (i fill up almost every day... )

I run good ol' fashion cheap ass 87 octane at the low low price of $4.00 a gallon.

Quote from: SecondsFromTheFall on July 04, 2008, 11:26:29 PM
I run good ol' fashion cheap ass 87 octane at the low low price of $4.00 a gallon.

i pay the LOW LOW prince of 4.60 anywhere i can find it...     

welcome to california 

I run the lowest octane possible that won't give me knocks and pings.

89 octane for me. 87 runs like hell and knocks like crazy.