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Correct me if I am wrong but the new 08 VRS have O2 sensors. I would think this would make things ez'er when it comes to slip on pipes. I thought the O2 sensor adjust the air/fuel mix as needed. Hence you change mufflers add better airflow on top and the sensor sences more O2 and richens up the mix. I am sure it has a limit however when I did this kind of work on a carb, it was only a few jet sizes bigger. Come on all you self wrenchers, lets hear it.
 

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This will not make exhaust upgrades easier. These are narrow band Nernst O2 sensors and only provide feedback during closed loop operation (idle and cruising). The ECM will be open loop using table values as before during WOT and other high load operation.
 

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I thought the 02 sensors were only on the air cooled bikes. I am certain all will need to go to them eventually and hopefully it will be an honest, wideband sensor.
 

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Kicking cancer's ass
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02 sensors are on the 08 V-rods.
 

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matt blk & fire hot
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?

DFinch said:
02 sensors are on the 08 V-rods.
Just O2? no cat right? metrics have cats now.
 

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The V-Rod still reads manifold absolute pressure to determine intake air flow and from that determine injector pulse length ( not unlike the old D-Jetronic system ) where the the rest of Harley's line has gone to using what is called an Alpha N system that uses throttle position and crank position to determine air flow and from that injector pulse length. The V-Rod doesn't yet require a catalyst to meet air quality standards, the air cooled bikes do, some have had cats for many years now. These were two way cats that did not require a feedback loop to operate. Modern three way cats need the O2 sensor to trim mixture so the cat can work properly. I am not aware of any need for an O2 sensor on the V-Rod since the engine management reads air mass directly. I do not believe there in any )2 sensor on these bikes.
It is simple enough for a pipe manufacturer to include a threaded mount for an O2 sensor. All BMW's require an O2 sensor and the various pipe manufacturers include proper mounting points in their pipe designs for BMW's. The same is true for just about all the current European bikes. I know Ducati's and Aprilia's have O2 sensors and it hasn't stopped the aftermarket from making plenty of pipes for these marques.
 

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I'm 'avin hoops
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All the EU bikes have a cat in the exhaust system.
 

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SNAFU
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The O2 sensor on the '08 bikes and the previous '07 Air Cooled bikes IS NOT wideband. The ECM system used on both the Air Cooled bikes and the V-Rod is still the Delphi Speed Density system, neither has changed to an AlphaN system and I doubt they ever will. It's far more likely they would go to a mass air system than backwards to an AlphaN. IMHO it will stay a Speed Density system for the forseeable future with the O2 sensor there to help adjust AFR for emissions. I'm not sure if the new VRSC's will use a catalyst in the 3rd volume but they have been using a 2 way cat on the international bikes since the very beginning so it wouldn't take much to add them to the US spec bikes.

As far a I know the O2 sensors are not specifically intended to maintain a 3 way catalyst but that may be their ultimate desire.

Just remember, because it has an O2 sensor DOES NOT mean it can adjust for pipe changes. The Harley system CAN NOT adjust for pipes, it's a narrow band system that only works at partial throttle. Idle, WOT and acceleration are still open loop.
 

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All international models apart from Japan have the cat.
 

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also remember that the bikes have a adaptive learning for a total of 32%
22% is closed loop correction and 10 % is adaptive which is lost at every key off cycle! some mods added will be corrected with the system. but remember when making an exhaust change where volume is completely different to remember to make the necessary changes to spark timing as well!
 
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