Hot Gas in an Eldo - Issues Down the Road?

[GuzziChris]

My buddy just bought a '74 Eldorado and he's saying it runs much stronger with a hot race gas (110 octane?) mixed in... is this going to be an issue with that 40 year old lump of an engine? The bike is in great shape otherwise, I believe it has the replacement cylinder sleeves (not the chrome bores).
Thanks

[lucian]

I don't think it will really hurt anything but his wallet. If the bike knocks or pings with 91 octane there is something wrong with the bike not the fuel. The engine should run at peak performance with the recommended octane, higher octane fuels do not contain more energy, only burn more predictably under certain conditions.

[Chuck in Indiana]

Probably has loose valve guides. Oil gets into the cylinder, forms carbon, makes the engine ping. Does is smoke briefly on startup?

[Vasco DG]

It's a 40 year old vehicle. Has it ever had any major engine work? Somebody may of flung a new set of jugs on it at some point but apart from that it's still likely to be a shagged out shitter. Methinks the high octane wonder fuel is more wishful thinking than reality.....

[Cam3512]

OP never mentioned pinging.  Just asking whether the high octane fuel will hurt?

[Chuck in Indiana]

OP never mentioned pinging.  Just asking whether the high octane fuel will hurt?

His wallet.. 

[oldbike54]

 Isn't high octane fuel actually cold and not hot ?  Yeah , the owner of said loop needs a butt dyno calibration , the current one is faulty .

  Dusty

[John A]

High octane just means it burns slower. It'll be harder on the exhaust valves and you'll be able to see the header pipes slightly red at night unless you tune to use that octane. By tune I mean piston crown shape,chamber shape, compression ratio, cam profile,timing,carbs and on and on, just to be chained to your fuel supply. Tell him to take the advice given and run pump gas or he'll be in for a learning process

[Two Checks]

With the low compression it could foul the plugs and combustion chambers with deposits.
Use the proper fuel.

[Lannis]

With the low compression it could foul the plugs and combustion chambers with deposits.
Use the proper fuel.

 :1:

For a Moto Guzzi, the most important thing SHOULD be that it can use fuel that you can buy anywhere, especially hundreds or thousands of mile from home.

What good is a bike that you can only fuel from a can of (possibly illegal non-road-taxed) high-octane race or aviation fuel?

Lannis

[normzone]

You guys are cracking me up.

In my Eldo experience, circa 1980 - 1990, pump premium was 94 octane. The bike loved it.

I could buy 100 octane from a local supplier. The bike REALLY LOVED IT.

From the same source I could also get 110 octane. The bike did not like it - didn't run as well as the 100.

No "red pipes". Can't tell you if the engine wore out prematurely, I sold it after putting 115 K miles on an engine that I believe already had 115 K miles on it when I found the bike.

[normzone]

The hazy part is my guessing if a 1972 Eldo, found sitting for three years in 1979, had 15K or 115K on it.

The guy I bought it from got from a guy who crashed it that owed him money.

I spoke with the guy who crashed it once - he was a bit of a bullshitter I thought, but he said he'd got it from the first owner. That would give four years to accrue 115K in Northern California.

[cruzziguzzi]

There's the potential for a "perfect storm" scenario in which introducing higher octane fuels to and older and un modified (ignition, fueling) engine can ultimately lead to "addicting" it to said fuel in that (here I deliberately over simplify) the build up of solids - carbon and the like - can lead to needing the higher octane to cope with a compression ration increase leading to...


Todd.

[normzone]

Wow. Motorcycle fuel addiction. That could explain a lot...   

[CalVin2007]

  O.P. said race gas mixed in....and in an engine that may well want a bit more octane than current pump swill provides I can see the benefit. Straight 110? No, but a light dose mixed in to bump octane a couple numbers will certainly help if the engine is pinging or near detonation, and will certainly not damage it. Don't tell anyone, but my CalVin likes a quart of 110 in 5 gals of pump swill......

   Oh....and yes the burn is slower and likely cooler with the race 110....it's not "hot".

   Terry