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Hi all, new to this forum. I had a question and figured I would post it here. I have a 2013 RC8R with a Comp Werkes slip on and hi flow air filter (don't know what brand the previous owner used). Had my bike tuned over the weekend and wanted some opinions. I am very familiar with car tuning and AFR's but the tuner that tuned my bike has the AFR set a little over 14:1 and said that was the ideal point. This seems a little lean to me. 93 octane/Power Commander 5. Please give me some opinions and also if anyone may have a map for my particular setup.
 

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I'm sure you've got your cycle tuned right by now. I'm in St. Louis and had mine dyno'd also. this guy has done your set up just beforee he did mine with a Jester68 pipe on mine. if you still need info on the right map, its Cycle House Performance, in Mo. 314 270 3312
 

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Hi all, new to this forum. I had a question and figured I would post it here. I have a 2013 RC8R with a Comp Werkes slip on and hi flow air filter (don't know what brand the previous owner used). Had my bike tuned over the weekend and wanted some opinions. I am very familiar with car tuning and AFR's but the tuner that tuned my bike has the AFR set a little over 14:1 and said that was the ideal point. This seems a little lean to me. 93 octane/Power Commander 5. Please give me some opinions and also if anyone may have a map for my particular setup.
I lifted from wiki/
I guess 14.1 is the tuners middle road, safety tune
The air–fuel ratio is the most common reference term used for mixtures in internal combustion engines. The term is also used to define mixtures used for industrial furnace heated by combustion. The AFR in mass units is employed in fuel oil fired furnaces, while volume (or mole) units are used for natural gas fired furnaces.

Air–fuel ratio is the ratio between the mass of air and the mass of fuel in the fuel–air mix at any given moment. The mass is the mass of all constituents that compose the fuel and air, whether combustible or not. For example, a calculation of the mass of natural gas—which often contains carbon dioxide (CO
2), nitrogen (N
2), and various alkanes—includes the mass of the carbon dioxide, nitrogen and all alkanes in determining the value of mfuel.[2]
For pure octane the stoichiometric mixture is approximately 14.7:1, or λ of 1.00 exactly.
In naturally aspirated engines powered by octane, maximum power is frequently reached at AFRs ranging from 12.5 to 13.3:1 or λ of 0.850 to 0.901.
Air-fuel ratio of 12:1 is considered as maximum output ratio, whereas the air_fuel ratio of 16:1 is considered as maximum fuel economy ratio.
 

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14.7:1 is stoich.

Lean make better power and snap, but runs risk of hotter cylinder temp. Gas cools things.

Generally speaking from 12.5 - 14 should be ok and safe. Most guys err on the side closer to 12 to reduce explosions, so hopefully your tuner is either good and confident in his ability to tune close to the higher end for power and has the knowledge to keep it together.
 
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