Sal Paradise
Hooligan
I would be worried about predetonation/pinging. Seems to me thats more likely in the summer. Also, I have the carb jets richened up so lean is not a worry for me.
Premium gas?
- Thread starter cycleddie
- Start date
I would be worried about predetonation/pinging. Seems to me thats more likely in the summer. Also, I have the carb jets richened up so lean is not a worry for me.
Stars&Bars
Two Stroke
+1 on the Premium fuel from a name brand station. The extra money spent on the Ethel ain't much when your only putting in 3 or so gallons. I found using premium while riding two-up seems to keep the snap in the throttle particularly at highway speeds on 100 degree days.
sweatmachine
moped
Bottom line: if you don't need high octane gas you're wasting your money. The Bonnie doesn't need high octane gas. It's your money, waste it as you like. I'd rather spend it on broads. 
RumRunner
Street Tracker
Actually when air is hotter it's less dense, so do not need as much fuel. The colder the air is the denser the mixture the more fuel you require. The same basic reason that when you first fire up a bike when it's cold out you need to use a choke (to richen it up) as the engine builds heat it does not need as much fuel and take the choke off.
KingOfFleece
Street Tracker
Go to the Mobile website. Tthere is a ton if info. on octane and why/what to use.
Bottom line-Sweat is correct. Using more than is needed serves no purpose and may in fact hurt performance by nature of the slower burn in high octane fuel.
Now, the QUALITY of today's gasoline is another subject altogether...........
Bottom line-Sweat is correct. Using more than is needed serves no purpose and may in fact hurt performance by nature of the slower burn in high octane fuel.
Now, the QUALITY of today's gasoline is another subject altogether...........
pepper
Street Tracker
There ya go man, answers both for and against. I've got an '03 790 as well. The manual calls for 89 for our bikes. Will it run on 87, yep. Will it run on 91? All day long. If wasting pennies is a concern you'd be better served keeping the bike in good tune, ensuring your tire pressures are where they need to be and not riding overly agressive. It only takes a couple miles per gallon shift to lose the small gains made at the pump.
bonZa
Street Tracker
It's your money, waste it as you like. I'd rather spend it on broads.
wow, you must know some cheap broads with all that cash you are saving
can you send some around to me?as for me I've always used premium in this bike. wouldnt use cheap shit even in my whipper snipper
sweatmachine
moped
It's not "cheap shit" it's just cheaper shit than the "ultra premium" that you think is better for some reason. It is no better for your bike.
This thread reminds me of one of my favorite sayings:
"Never try to teach a pig to sing. It wastes your time and annoys the pig."
travellingtenor
Scooter
I used to formulate gasoline, bunker fuel, and jet fuel for Chevron. Using a higher octane than you need in your engine IS a waste of money. My T100 gets regular, however, my 1224, 12.5 to one compression ZRX gets premium. But, you may do as you see fit. It's your money.
KingBear
Hooligan
I thought I got a few extra MPGs out of premium but finally concluded that the difference was within the usual margin of error. I run 89 as recommended my the manufacturer, just as I used their specified oil, etc. I haven't changed any critical parts or deviated from a factory set-up and my bike has run flawlessly for nearly five years. Eventually I will install the TORs, which I feel is still factory spec.
But that's just me.
But that's just me.
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sweatmachine
moped
Actually, you should get LESS MPGs burning a higher octane than needed.
mikenva
Rocker
Do you need high octane fuel on a bone stock bike ? No .Do you need it on a lightly mod bike with pipes air box and 3 deg more timeing ?yes Will it hurt your mpg on ether ? No.Will it help your mpg on a bone stock bike? No. Will it help your mpg on a lightly mod bike ? Yes. Is it safer on your motor ? Yes. If the bike gets over heated it wont build as much heat. Its well worth a few cents.
TC_Dick
TT Racer
Actually, that's not true. Octane is not a measurement of how much "go" is in your gas. It's a measure of how much energy is required for detonation. In a higher compression engine, higher octane fuel is needed to ensure the detonation is not premature.
Sweatmachine is totally correct in what he's saying. you may actually get fewer miles per gallon using over-rated fuel, due to the energy requirements for detonation.
mikenva
Rocker
You need to read what I said .more timing = more detonation ,to much to soon = burnt up motor. More timeing on these bikes = more hp.I think I know alittle about making hp on these bikes. PLUSS jeff has a stock ecu box on his bike he might change his mind with the right timeing on his bike.Just for your info me and Jeff know each other well he has the stock 790 cams in his bike that came out of mine.
sweatmachine
moped
Mike, that's what I've been saying man. Modified bikes need premium. Stock bikes do not. It's a waste of money if it isn't needed.
I'm done with this fucking thread, sheesh.
I'm done with this fucking thread, sheesh.
tribear
Street Tracker
Ha ha! I hear ya man.
87 in the Scram, 87 in the Bonnie, 87 in the Tiger, 87 in the WR....
Never a problem, great mileage, no detonation, no over heating, no under heating, all elevations/temps/humidities/cosmic radiations....yata yata...
All engines/valves/carbs/throttle bodies have been apart and reassembled by me...no visual damage, no extreme deposits.
Fill 'em and ride 'em.
six by six
Two Stroke
Fill 'em and ride 'em AMEN! I was going to chime in on what octane is for and it's not really better gas blah blah blah. It took me a while to realize that these engines are pretty much bullet proof. Not like the straight six in my jeep but close.
tooblekain
750cc
+1. Ever since I bought my Bonnie Ive been tracking gas useage and MPG. When you use premium you actually get 3-4 MPG less!!! That might not be much, but my tracking sheet has grown quite long. You actually get better MPG with just regular grade gas.
My Bonnie is 100% bone stock.