A few things I need to know?

[Susuki_Jah]

OK first off. it takes my bike about 5 mins to warm up properly. Does this sound right?

second I started putting 93 octane gas in my bike. runs great. but last night in 6th gear at full throttle I started missing. right under full throttle it was fine but as soon as I hit it it would missfire. So I slowed down hit a light then start back up again. and no problems. just wierd that it randomly came and then went.

what is the best octane to run in our bikes?

[SPARKPLUG1977]

run the cheap stuff.

[manofthefield]

and 5 minutes is about right for warm up, depending on ambient temps

[Susuki_Jah]

yea about 70 degrees.

so the best to run is 87?

[scootr9718]

but last night in 6th gear at full throttle I started missing. right under full throttle it was fine but as soon as I hit it it would missfire.

this is probably a fuel delivery issue...sometimes with the GS's, at high speed, the fuel vaccum isn't enough to get the gas to the carbs...if this happens, try switching the petcock to PRI...usually solves the problem.

[indestructibleman]

87 is fine.  the owner's manual says 85 or more.
unless your engine is pinging there is absolutely NO advantage to running higher octane gas.

cheers,
will

[Susuki_Jah]

this helps alot thanks guys.

[coll0412]

I did get the owners manual with my bike, but under the seat there is a white sticker on the fender, it says

"Fuel: Unleaded Gasoline; 91 min RON"

I would assume that is 91 octane min requierment

[SPARKPLUG1977]

in a perfect world with every last bit of stock compression.

[mjm]

I did get the owners manual with my bike, but under the seat there is a white sticker on the fender, it says

"Fuel: Unleaded Gasoline; 91 min RON"

I would assume that is 91 octane min requierment

There are two different ways of determining octane - one is the RON (Research Octane Number) and the other is the MON (Motor Octane Number).  MON is usually quite a bit lower than RON.  United States regulations require pumps be labeled with the RON+MON divided by 2.

91 RON plus 80 MON is about 85 in the US system.  For info on what RON and MON really mean check out

http://chemistry.about.com/cs/howthingswork/a/aa070401a_2.htm[/list:u]

[Roadstergal]

...and the RON+MON/2 is known as AKI, anti-knock index.  That might get you a Trivial Pursuit pie slice, or someting.

[ericjmense]

I thought higher octane burns clearer so it would be better to run gas that creates less carbon build up right?  Or am i missing something in my logic?

[ericjmense]

[indestructibleman]

the only thing higher octane does differently is detonate later.
higher levels of compression will cause gasoline to detonate sooner.  this is pre-ignition, otherwise known as knocking.
so engines with higher compression ratios require higher octane.
an online friend who's a certified honda master mechanic and former pro racer laughs about all the people he sees at track days paying outrageous amounts for race fuel to put in their streetbike engines.

http://www.ftc.gov/bcp/conline/pubs/autos/octane.htm

cheers,
will