Author Topic: fuel consumption and performance  (Read 2734 times)

Online bsa-bill

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Re: fuel consumption and performance
« Reply #15 on: 17.01. 2014 10:51 »
Just had a thought (happens now and then)

Aerodynamics, not to many of us here use fairings as far as I can see in pictures, and they do make diiference as you find the first time you brake with one fitted.
Doesn't explain the difference from then ttll now though    and modern bikes are usually faired to some extent - it's a factor though     
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Offline Briz

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Re: fuel consumption and performance
« Reply #16 on: 17.01. 2014 11:15 »
A lot of you guys are comparing apples to oranges. Yeah, modern sportsbikes make comparitively poor gas mileage, but they make 4 times the power! You cant make power without burning fuel.
If you built a mega-strong A10 and boosted it to make 150hp, that'd get lousy mileage too.
And nobody buys something like a huyabusa as serious everyday transport!

That said, there is often little rhyme or reason to mileage, and like horsepower figures, owner estimates are often...ummmm...imaginative! Friend of mine once had an early 70s Lincoln Continental; 7.6ltr big block and the weight of the titanic. Reckoned he got 22mpg. Yeah right!.

Online KiwiGF

  • Last had an A10 in 1976, in 2011 it was time for my 2nd one. It was the project from HELL (but I learned a lot....)
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Re: fuel consumption and performance
« Reply #17 on: 17.01. 2014 11:23 »
bsa bill, your onto it very likely, aero dynamics might very well be a factor here, cars have progressed a lot with aerodynanmics, but maybe bikes not as much? There is only so much one can do to improve the aerodynamics of the average biker, and of course fairings are generally only fitted to the modern sporty bikes which are not meant to be good on fuel anyway.

The BMW range might give a clue as to why bikes have not progressed as well as cars in terms of fuel consumption? Have they progressed?

Re modern engine tech, I've recently done the valve clearance job on my triumph street triple and that was a real eye opener for me, requiring moving lots of bits out of the way to do the job, it has no carbs just throttle bodies with computer controlled injectors, half the 8 hour job (required every 8000 miles) was unplugging and re connecting the engine electrics!

New Zealand

1956 A10 Golden Flash (1st finished project)

1949 B31 rigid “400cc hot rod” (2nd finished project, + favourite bike)

1949 C11 rigid, but why!!! (cos it was cheap)

1937 B21, project missing parts, mission impossible?

GL1800 Goldwing, well, the wife likes it

KTM 950 ADV, cos it’s 100% nuts

1952 Armstrong Siddeley Whitley for rainy days (with wife

Offline cyclobutch

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Re: fuel consumption and performance
« Reply #18 on: 17.01. 2014 14:25 »
Aerodynamics certainly becomes a factor at higher speeds – somewhere beyond 60/70 per I’d guess. I took my ZRX (or whatever it is – it’s the Lawson looking thingy) down to Strasbourg last year for a few days riding the twisties out that way. Out on the mountain roads with significant changes in incline and all types of curve which keep speed down but running an awful lot of throttle in lower gears the usual mpg wasn’t much compromised. The run there and back from Calais (around 400 miles each way) taken at high speeds – sometimes around 120/130 indicated for stretches really hoovered up the gas.

I’d still expect a mid-sized bike with good performance to be considerably better than they are.
Various, including ...
'58 Iron Head Flash Bitza


Offline chaterlea25

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Re: fuel consumption and performance
« Reply #19 on: 17.01. 2014 21:05 »
Hi All,
""Friend of mine once had an early 70s Lincoln Continental; 7.6ltr big block and the weight of the titanic. Reckoned he got 22mpg. Yeah right!.""

Reminds me of the story about the forecourt attendant who asked the owner of such a beast
"can you turn it off so as I can catch up!!!!  *yeah* *yeah* *yeah*

John
1961 Super Rocket
1963 RGS (ongoing)

Offline duTch

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Re: fuel consumption and performance
« Reply #20 on: 08.02. 2014 00:23 »
  Read through again, missed some bits, Kiwi- maybe I need a 376, instead of my 389...¿
It's interesting to see how other bikes consume, but I was really only curious about comparing A10/7 consumption, bikes of similar specs, like there's a difference between my plunger and the Road Rocket, 357/356 cams, and 7.25/8.~ pistons, and crank- wheel sprocket ratio(?), but basically same.
 Also my Gutzi comparison is with only itself over a 20 year time frame, a couple of weeks
ago did a trip to Tamworth, ~380 miles each way, and still had the same consumption rate as always- 200 miles/20 litres tank, on cue....!
       *beer* *beer*
Quote
Back in the 80's I used an A10 for commuting to work ...a 40 mile trip...and used to easily get 60mpg but I think the difference then was how much easier it was to get about. I used to try and do the whole trip without coming to a stop and putting my foot down....and often managed it!
Doubt you could do that nowadays...
*eek*

    Yeah sometimes I forget to do that too....
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia

Online Triton Thrasher

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Re: fuel consumption and performance
« Reply #21 on: 08.02. 2014 10:03 »
Hi All,
""Friend of mine once had an early 70s Lincoln Continental; 7.6ltr big block and the weight of the titanic. Reckoned he got 22mpg. Yeah right!.""

Reminds me of the story about the forecourt attendant who asked the owner of such a beast
"can you turn it off so as I can catch up!!!!  *yeah* *yeah* *yeah*

John

I had a 1967 Mercury coupe, with probably similar 6.4 litre V8 Ford engine. You could get 14 mpg.