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Discussion Starter #1
Is there anyone here with a degree in hydro-dynamics? Where is the best location to place the dual autotune for a PCV on the other exhaust to give the best numbers for the PCV, ie no eddys, not too hot, not at tip of exhaust......

Anyone put one of these on, or any ideas?
Thanks
 

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Discussion Starter #5 (Edited)
As the autotune is held up in customs I'm not sure of the length of cable to get to front header. Previous sensors I've seen are more or less under the rearsets. But That's on inlines with single exhaust.
 

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Are you going to run dual Auto tune set ups?
or can the auto support running two 02 sensors?
The one I have I bought for my R1 but it only has one input. Not sure how you will make the table adjustments to run a dual set up.
Personally I would put it in the collector so you get an equal amount of flow from both heads and tun it to get that number right. even dyno guys typically only run one sniffer.
 

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Nice. didn't realize it supported dual sensors.

and no they do not have to be exact. I would make sure they aren't so close they restrict flow.
Make sure they aren't in a bend.
and make sure they are far enough away from the collector to not be picking up exhaust from the other cylinder.
 

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Nice. didn't realize it supported dual sensors.

and no they do not have to be exact. I would make sure they aren't so close they restrict flow.
Make sure they aren't in a bend.
and make sure they are far enough away from the collector to not be picking up exhaust from the other cylinder.
So just about anywhere above the oil filter and somewhere it doesn't get hit by the shock? :cool:got it
 

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Not closer than 30mm to the ex.port IMO. Usually you place each Oxygen sensor about 100 - 150mm from the ex. valve port though

Any supporting information for the distances you posted?

I already have mine installed, but just curious.
 

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The oxygen sensor should be in such a distance that exhaust gas has a steady flow in order to have a good reading. The closer to the exhaust port, the hotter the gasses and the greater their exiting velocity from the chamber.
Also, during the engine's cold start, the fuel system enriches the mixture to get the engine running and part of unburned fuel usually escapes the exhaust port and can damage the O2's materials in time.

Oxygen sensor does an analogue reading on the oxygen contained in the exhaust gasses. To do so it "compares" the gas sample that flows through it against a sample of fresh oxygen that it is embed in it's core and subtracts the measuring differences. That means that the results are not instantaneous but gradually extracted.


So oxygen sensor's sample chamber must be in the gas flow path but the gas shouldn't exceed it's core temperature.
That's why the sensor has 4 wires on it. Two of them transmit the measured voltage and the other two are to preheat the sensor's core, in order to have accurate readings as soon as possible (usually takes 8 sec). That's about 500C.
Installing it very close to the exhaust port would force it to work in a 800-1000C environment and that should effect the readings.

You don't have to be very precise to the distance from the exhaust port. Ten millimeters more or less won't change anything.
Put it between 100 and 200mm from the exhaust port, where it fits better and you're golden
 

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Actually SKOTTIE had to move one as it gave false lean readings and the map would not effect cyl.1 from 7-9k after several pizzas and part swaps from my bike our tuner decided to move the sensor out of the eddy current and all was good.
Call Mike at Kyle ;)

BTW I have a base map for you...until you get set-up.
 

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Supporting info like what? Do you have something specific in mind?

Looks like you answered it with your follow up post.

Was just curious how you came to the numbers you posted as I'm still learning.

Muchas gracias sir ;)
 

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Looks like you answered it with your follow up post.

Was just curious how you came to the numbers you posted as I'm still learning.

Muchas gracias sir ;)
I've heard it before among other technicians discussions but I also observe OEM fitting and learn from the factories themselves

That's why I uploaded the picture of the RC8's headers.

You'll notice the same is you look a S1000R exhaust header as well



And an R1200 too

 

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Discussion Starter #18
Autotune arrived out of the blue, got an idea where to stick them. Front on on straight next to oil filter. Rear im thinking next to shock, on a bit of a bend but not much room anywhere. Ideas? Wingnutt's map is working for now. Cheers.
 

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Autotune arrived out of the blue, got an idea where to stick them. Front on on straight next to oil filter. Rear im thinking next to shock, on a bit of a bend but not much room anywhere. Ideas? Wingnutt's map is working for now. Cheers.
If I were you, I'd mount the rear, underneath the shock somewhere next to the shock link.

Remember that as long as your PAIR system is engaged, you're readings will be off due to extra air pumped in the exhaust
 

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Discussion Starter #20
If I were you, I'd mount the rear, underneath the shock somewhere next to the shock link.

Remember that as long as your PAIR system is engaged, you're readings will be off due to extra air pumped in the exhaust
PAIR system removed and blocked off. Very limited on space down below, and ground clearance and where everything moves with riding. Also not sure about radiant heat from all that pipe. Plus can't be after point where pipes join/combine then split again.
 
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