Gas Mileage

[The Foggster]

Despite mostly city driving, my Guzzi has run flawlessly for the 1+ year I have owned her. Agreed that you need to keep the rpm's up there. I try not to be below 3,500. Actually 3,500 is in the middle of the bouncing needle....hmm....is it really 2,000 or 5,000???????????????

 

Bob

 

Just to add my two penneth. On a tour of Scandanavia the best I got was 55 MPG Imperial. That was at a steady 50 mph. The only thing that annoyed me was my friend was on a Hardly Moving Son 883 and he got 75 MPG Imperial.

 

In case you think I am a wuss, if you get caught doing more than 50 KPH over the speed limit in Norway its straight to jail.

 

Normal riding then its 40 - 45 imperial.

 

The Foggster

Firm of Stance

and of Buttock

[Gio]

2000 V11 Sport w Mistrals, open air box and Power Commander gets me typically 35 mpg imperial (12.5km/l) around town and 42 mpg on open highway ...

 

Gio

[Skeeve]

Well, after reading all the posts and discussing gas mileage with several local guzzisti, it appears that the consensus would indicate that the V11's inefficient design correlates to 38 mpg, plus or minus, on average. I am giving up the chase for better mileage and i'm just going to ride and enjoy this great bike.

 

Mike Rich hi-comp pistons will improve upon this slightly, as they're optimized for squish on the V11 head & relatively flat-topped [vs. other hi-comp pistons (FBF, cough, cough) which have a higher compression ratio at the expense of efficient flame travel w/in the combustion chamber.]

 

As MR states it, the nominal 10.5:1 CR of the stock pistons aren't, due to their non-conformance to the combustion chamber dish in the head, and his pistons merely achieve the quoted factory CR. Look up the thread on high compression pistons from a year or two back, and all will be revealed!

[guinzomoto]

My 93 Cal III I.E. gets 47-55 mpg us. My old LeMans IV got 45-50 mpg us. The best I have ever gotten out of the Scura is 42, worst is 34, mostly stock just a PC III added. All the fuel injected Guzzis got 50 mpg until 98 when the EV came out and low 30s were the norm until some riders started figuring out it was the new sensor in the valve covers that were added to the system, foiled it in various ingenious ways and got back into the 50s. Breva riders I talk to claim they run in the 50s and so does a Norge owner I know. The reports on the new 1200 Sport all put the fuel mileage at an average of 44-45 so I think the V11s just get poor mileage. Has anyone tried foiling the temp sensor in the head? Mario

[tmcafe]

Comparing HDs and Guzzis on mpg is like comparing apples and oranges.

 

The internal design follows a completely different philosophy.

 

HD= low revving, long stroke engine. Undersquare bore/stroke ratio.

 

Guzzi= high revving (for a pushrod twin), short stroke engine. Oversquare bore/stroke ratio.

 

Combustion chamber design is also quite different.

 

My V11 LeMans averages 38mpg. It gets in the low 40s at higher elevations.

Indeed, and that can't be changed. But it looks like not all oversquare twins have poor gas mileage. The BMWs 1150 engines all appear to have better gas mileage while being bigger and still oversquare (101 mm X 70.5 mm). Not to mention the new 1200s, both BMW and Guzzis do much better than the V11. There's a combination of factors beyond the undersquare/oversquare issue that make the V11 a gas guzzler among bikes. Probably combustion chamber is right up there. The only thing that I don't like about the V11 is the gas mileage, (the small alternator comes way down the list as the next single gripe), otherwise it's sooo cool.

[docc]

I'm thinking the nominal compression on the V11 (at least the 2000) is 9.3:1.

 

I have gotten up to 40-41 m/USG, but 35-38 is much more typical and as low as 32.5 in the colder temperatures.

 

I thought my recent 100,000 Km tune-up might up it all a bit, but it runs so great and I flog it and cog it so hard, the mileage stays about the same.

 

I'm sure the combustion chambers and all that are contributing, but I believe the cam overlap and lift are to 'blame.' The cam is also probably to blame for the finicky idle, fussy high state of tune and overall lusty brio of the beast.

[tmcafe]

About 31 mpg yesterday between two fill-ups on the highway, average speed 80-90, pushed occasionally to 120-140--speeds were indicated (just taking advantage of empty straights, dry pavement and clear and sunny weather)

[rocker59]

Indeed, and that can't be changed. But it looks like not all oversquare twins have poor gas mileage. The BMWs 1150 engines all appear to have better gas mileage while being bigger and still oversquare (101 mm X 70.5 mm). Not to mention the new 1200s, both BMW and Guzzis do much better than the V11. There's a combination of factors beyond the undersquare/oversquare issue that make the V11 a gas guzzler among bikes. Probably combustion chamber is right up there. The only thing that I don't like about the V11 is the gas mileage, (the small alternator comes way down the list as the next single gripe), otherwise it's sooo cool.

 

Yes. There are a combination of factors.

 

The BMWs have 4valve heads, modern combustion chambers, and closed loop efi.

 

I can tell you that on a trip last year, loaded and travelling at the same highway speeds, my friend on his 2007 model XL50 1200cc Sportster returned 10mpg better than I did on my Nero Cosa. He was seeing 47mpg and I was seeing 37mpg.

[tmcafe]

Yes. There are a combination of factors.

 

The BMWs have 4valve heads, modern combustion chambers, and closed loop efi.

 

I can tell you that on a trip last year, loaded and travelling at the same highway speeds, my friend on his 2007 model XL50 1200cc Sportster returned 10mpg better than I did on my Nero Cosa. He was seeing 47mpg and I was seeing 37mpg.

Twin spark also helps, it seems. The 2004+ Rotax engines are TS, and the gas mileage on those things (which is already super sweet, sometimes even in the 60s) is even better. The new Guzzis are twin spark too.

Anyway, it sucks to have Hardly Ableson be better at anything (okay, we'll let them get the award for vibration and heat from the rear cyl )