Author Topic: Air fuel ratio A10 engine  (Read 984 times)

Offline Viking

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Air fuel ratio A10 engine
« on: 03.02. 2016 21:02 »
What is the optimal Air fuel mixture ratio in the A10 SR engine ?
14,5 or ?

I am planning to fit at AFM meter in my A10 SR, to test if the mixture i correct in all driving conditions....

Would like to have a Rolling road test bench, But i am limited in space...

Offline BSA_54A10

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Re: Air fuel ratio A10 engine
« Reply #1 on: 03.02. 2016 21:43 »
This is a how long is a piece of string type question.
The text biook number of 14.715 makes a bold assumption that you are burning OCTANE ( 8 carbon + 18 Hydrogen ).
However in reality what is in your tank is any else but Octane and with the advent of real time engine management, we now have "fuel" which is mosty waste organic solvents and by-products from the plastics/fertalizer industry.
Bike Beesa
Trevor

Offline muskrat

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Re: Air fuel ratio A10 engine
« Reply #2 on: 04.02. 2016 18:37 »
G'day Viking.
Orabanda's dyno findings are around 12 to 12.5:1
http://www.a7a10.net/forum/index.php?topic=3122.msg21340#msg21340
Cheers
'51 A7 plunger, '57 A7SS racer now a A10CR, '78 XT500, '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
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Offline chaterlea25

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Re: Air fuel ratio A10 engine
« Reply #3 on: 04.02. 2016 19:49 »
Hi All,
A kind of parallel question, recently I picked up a CO2 meter, that tests the CO2 in the exhaust gasses
Of course no instructions came with it !!!
Does anyone know what % CO2 I should aim for in the exhaust gasses??

Cheers
John
1961 Super Rocket
1963 RGS (ongoing)

Offline muskrat

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Re: Air fuel ratio A10 engine
« Reply #4 on: 04.02. 2016 21:59 »
Good  *????* John. I'd like to know as well.
The only figure I could find was 12-15%. So in ppm 120000-150000.  *dunno*
 Viking, the 14.5:1 would be for modern fuel injected lean burn type engines.
Cheers
'51 A7 plunger, '57 A7SS racer now a A10CR, '78 XT500, '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
Australia
Muskys Plunger A7

Offline chaterlea25

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Re: Air fuel ratio A10 engine
« Reply #5 on: 04.02. 2016 22:33 »
1961 Super Rocket
1963 RGS (ongoing)

Offline oka

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Re: Air fuel ratio A10 engine
« Reply #6 on: 15.02. 2016 10:42 »
I have aimed for between 12:1 and 13:1.

It is where you have the maximum horsepower and gives a nice margin to too rich 10:1 and too lean 15:1.

Modern cars which run 14.7:1 also have a lamda sensor which regulates the fuel injection. Not quite what we have with the Amal.  ;)