Is Premium gas a waste of money?

[scoobydoo]

I have always bought premium gas in the past, but with gas prices going up, does it really matter? My bike is all stock except a K&N filter, no timing mods or aftermarket exhaust. Just wundering what everybody else buys. Don't want to screw up something just to save a little.

[Serk]

If your engine isn't designed to use premium (I.E. High octane) gas, then using it will actually decrease your fuel mileage...

(Warning - Holy war to come!)

Higher octane basically just means that the fuel can withstand higher compression before igniting, so a very high compression engine will need higher octane fuel to avoid pre-ignition.

Our beloved Valkyrie's have all the technology, finesse, and high compression, as a 1976 Buick...

So unless you've done some really funky stuff to your engine, regular fuel is what a Valk needs to drink, I've been feeding mine regular for over 100,000 miles now...

Bottom line - Unless the manufacturer says to use higher octane fuel, don't...

[Probie (Scooter57)]

I've run Premium in mine most of the time, I have the timing mod and was told I need to run at least 90 Octane so I will run one tank of Premium then Regular or Mid the next tank.
There are a lot of guys here that will tell you that all ya need is Regular, I haven't been able to tell the difference and with the cost going up I may go with Reg all the time.

[old2soon]

Stock 99 i/s. Most of the time 87 octane. She seems to like it. Most of the CASEYS here-same price 87 or 89 octane. When that happens-to me it runs just as well. If this helps-i keep money on my wally world card-runs good on wally world gas also. As always RIDE SAFE

[Bobbo]

What Serk says.

I've used 87 octane for over 180,000 miles.  I have the IS ICM, K&N, Viking pipes and needles, and a few other simple mods.  Runs great on regular as Mr. Honda designed it for.

[R J]

Have to agree with Serk and Bobbo.    Regular.

Run MGM on 87 or 89 for over 242K miles, no problem.

[Serk]

Further explanation on my comment that using high octane fuel when not needed will decrease fuel economy:

1 gallon of gasoline has X amount of potential energy.

To boost the octant additives are added to the fuel...

That means that the more additives per gallon of fuel, the less gasoline there are in that same gallon, and thus the less potential energy in that gallon...

Make sense?

[Brad]

I run the regular 87 all the time.  While traveling in eastern Nevada and Utah they sell 85 and I run that when passing through.  No problem!!  As long as your not wasting my money, you can run what you want.   

[solo1]

Regular is ok for the Valk.

When i was young I thought the higher octane the better.  I tried aviation gas (100 octane)  in my Matchless thumper (7.2 compression ratio back then).  It ran bad and the mileage dropped from 60 mpg to 35 mpg.

[alph]

I’ll buy premium when I don't want to have any ethanol in my fuel.  When you’re buying 5 gallons, $2 more per tank full isn’t a big deal, just means I won’t buy anything in the store.

[Jabba]

I have a Dyna 3000 on the Std, and keep it set on... the #7 curve.  That's the most aggressive timing curve short of the settings for blown bikes.  It'll ping on anything less than 91.  So I run 93 in that one.

My IS is BONE stock.  She runs fine on 87 octane.

Higher octane actually burns SLOWER.  That's why it doesn't ping.  If you're running an aggressive timing curve, ie... sparking the sparkers further before TDC, you're more likely to need higher octane fuel.

MY stock valk likes 87 just fine.

YMMV.

Jabba

[Smokinjoe-VRCCDS#0005]

Regular will work alright in my bikes if I'm running the super-slab however when I hit the mountains twisties I can tell it needs higher octane to keep it from pingin' .90% of the time I shoot mine full of mid grade 87 seems to run great on the blue road and the mountains as well.

[thumper]

I'm glad this came up.  I have an 03 standard with a trigger wheel.  I'm told I need higher octane so I run mid grade.  Would love to run regular.  I've done it in the past and it seems to run fine.

[Bobbo]

I'm glad this came up.  I have an 03 standard with a trigger wheel.  I'm told I need higher octane so I run mid grade.  Would love to run regular.  I've done it in the past and it seems to run fine.

I used to have a 6 degree trigger wheel with the standard ICM.  It would ping under load with anything under 91 octane.  I decided the tiny lowend power increase wasn't worth the higher price of premium, so I went to the IS ICM and stock trigger wheel.  I think that works better for overall driveability.

[Jabba]

I used to have a 6 degree trigger wheel with the standard ICM.  It would ping under load with anything under 91 octane.  I decided the tiny lowend power increase wasn't worth the higher price of premium, so I went to the IS ICM and stock trigger wheel.  I think that works better for overall driveability.

Yeah... but go Dyna 3000 on #7 and it's worth it. 

at least to me it is.

My Standard will flat out EAT my IS.  Maybe it's just me.

I have a weird theory about that too.

2002 was the year that they made the LEAST Valks.  They knew 2003 was going to be the last year.  So they used up as many old parts that they had on hand as they could.  Then built what they needed to finish the model off.

I think I got a '97 engine.
 

Jabba

[Chattanooga Mark]

For most Valkyries, premium fuel only costs more money. With prices as they are now and rising, freshness of the fuel is also a consideration. Around here, all gas has ethanol (idiotic idea) and it goes bad much faster than before. I always by regular grade gas for all my vehicles. For the lawnmower and the bikes, I typically fill them from gas cans in the garage. I always add Sea Foam and Stabil to the gas cans to keep them fresh as long as possible.

All the best,

Mark
 

[sugerbear]

i try to fill up at a high volume station, run 87 octane, and have a stock 2k I/S.
when on a trip i try to do the same thing. had a valk since 2003 and never had a problem
with pinging or jets clogging. sometimes the bike sits for extended periods of time.

but thats my milage, which is 34-40 depending how i ride.

[Chiefy]

98 standard.  2BR 6 into 2 exhaust, stock jets.

I find that the bike has just a tad (nothing major) more muscle with high test.  It shouldn't, but it does, and I'm not going to argue it.......

Gas mileage is the same with mid grade, and it runs fine, no pinging.

For whatever reason, it seems to be more picky with mid grade.  Some tanks are fine, some run a little rough until the next tank, but it's not a problem.  But since that does happen, I've been reluctant to put regular in it.

[fudgie]

I have the ect and run cheap gas. Even ran cheap when I had the 6 deg TW. Never had a issue. BUT I will run the eth when I go west. Runs better. 

Cant wait for the fall river ride scoob. Had so much fun last year that I am looking forward to this more then Sturgis. Who thought that was possible......

[Jess Tolbirt]

I didnt read all the above but!!!

the higher the octane the slower the burn...
i dont know what octane pure alcohol is but its way up there...

now the slower the burn the more violent the explosion therefore you have to advance the timing to make the burn start sooner so when the explosion takes place its right at the time the piston hits top dead center or just a tick after that to push the piston down with a great amount of force...

running alcohol in my sprint i had to have the timing set at 32 degrees BTDC...

so if your timing is set at 9 degrees to sat 10 you would run a low octane for best performance...
of course compression has a lot to do with it too...

[Bobbo]

Here's an interesting write up on octane, pre-ignition, detonation, and burn rates:

http://www.2strokeheads.com/tech-octane-detonation.htm

[Super Santa]

2000 Interstate with a 6* trigger wheel.  I run 87 all the time for 74,000 miles now in less than 4 years (since I became the second owner).  Coastal areas up to over 14,000 feet and have very rarely encountered pinging.  Not often enough to even consider using higher octane.  The book says it is designed for Regular so that is what I run.  And I average between 35-40 mpg usually.  My average mpg for the past 32,000 miles is 37.26

[R J]

2000 Interstate with a 6* trigger wheel.  I run 97 all the time for 74,000 miles now in less than 4 years (since I became the second owner).  Coastal areas up to over 14,000 feet and have very rarely encountered pinging.  Not often enough to even consider using higher octane.  The book says it is designed for Regular so that is what I run.  And I average between 35-40 mpg usually.  My average mpg for the past 32,000 miles is 37.26

Correct me if i'm wrong, but isn't 97 octane Premium?

I run 89 in mine.   Yes, it is gasohol and I have not had a problem in 242K + miles.   If not in my home state, I run 87 and it also has a 6* wheel.    Had it since Lamonster came out with them.

[Super Santa]

You caught me on that one, R.J.  I corrected my post to 87.

[saabfxr]

I run the high test stuff,I can feel the difference, It will ping on heavy uphill pulls. Done some mods too and its the ping you dont hear that will cause problems. For the few $$ it cost to fill I wont take the chance. Get 40 with the gf most of the time,ridden sanely.I agree with the Valk is low tech and in most cases will do just fine on 87. All stock shouldnt be a problem at all. The gas today sucks so bad it isnt funny. I did notice more ping with the 6degree wheel than the ect mod I now run which makes sense. A good tune up and reg should be ok. If you have loud pipes,radio up  you might not hear the pinging.  My .02

[Hoser]

With no mods, regular is fine.  Don't know if anything modified needs premium, but it sounds reasonable.  Mine is stock, it does not.  Still dynos 99 HP and 97 ft lbs torque.  I don't worry about E10, either.  What ever is cheapest at the pump.  Hoser 

[R J]

I run the high test stuff,I can feel the difference, It will ping on heavy uphill pulls. Done some mods too and its the ping you dont hear that will cause problems.

Can feel the difference, that sounds like a butt dyno.

Ping on heavy uphill pulls.      That tells me you are lugging the engine.  Need to drop a gear or two.

I have several mods on mine, still run 87 and do not have any ping.   I pull the plugs every so often to look for little aluminum balls.  If i find them, it has been pinging.    Haven't found any in mine, but have found some in a blower bike.

[Valkernaut]

Rgr on that RJ - drop something, a gear, th' throttle, or the angle of the hill! I lost the "ping" a few years ago - along with watch ticking!

[shank]

Wow you all are confusing me. I have a 2001 i/s with cobra 6/6 pipes. the joker that owned it before me said it had been jetted for those pipes. (not sure how true that is ) but have always ran high octane i dont worry about millage when it gets low i buy more gas. never pinged seems to run like a scalded dog. am i wasting my money on high octane?

[Chiefy]

Wow you all are confusing me. I have a 2001 i/s with cobra 6/6 pipes. the joker that owned it before me said it had been jetted for those pipes. (not sure how true that is ) but have always ran high octane i dont worry about millage when it gets low i buy more gas. never pinged seems to run like a scalded dog. am i wasting my money on high octane?

One way to find out..........  ???

[shank]

True... whats the worst that could happen right.

[saabfxr]

I never lug the Valk. The dyno in in the buds garage next door. I put that crap 87 in it and it idles different, runs poor. Run what you want.

[Ferris Leets]

I never lug the Valk. The dyno in in the buds garage next door. I put that crap 87 in it and it idles different, runs poor. Run what you want.

Not being a smartass.

You have dynoed it with reg. and Hitest?  What kind of modifications have you made?  How much difference on the dyno for the gas change?
    Curious about this.  I did the ECT with rheostat and it idles much smoother and higher at all settings with regular than premium.

[Chiefy]

Some things don't make sense.  And maybe there is something wrong with the carburation or something else.  But some engines DO run better on High test then regular, even if their compression says they shouldn't.  

In 53 trips around the Sun I've learned that engines and most things mechanical are an exact science only in the design lab.

[saabfxr]

Yep and hp wasnt alot maybe a few at most but the response was different. I have ect mod, k&n, IS springs, viking pipes & needles, carbs are right on I got the tools for that, valves are right.  I agree about each engine being a little different my buds 98 is not the same as mine. I been wrenching on bikes,cars and stuuf for most of my life, got a clue.LOL.  I raised the tank some too that doesnt do anything till it moving ..real fast . didnt really notice much but some more intake noise from that. I guess its a little cooler air ??  I guess the turnup and fuel mixes in the aera when you live makes adifferance too. Runs better when I dont have that crap oxgenated fuel in it which is what I have here. The diff between stations here is crazy.