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Discussion Starter · #1 · (Edited)
we drilled the air box (using the Door Deadbolt installation kit holesaw)

and drilled the muffler using a 1 1/2 bi-metal hole saw (Lowes, Ace hardware, Home Depot)

and we took a long ride, and the wife is frying.
the back of her left thigh is on fire.
there is a little plastic scoop that catches air and blows it on the back of the rear cylinder head,
and we thought that air was coming out from there onto the back of her thigh, so we pulled that part of, and that seemed to help her thigh.



lean = hot
rich = cooler

EPA regs = Lean (lean means less gas and more air = less gas molecules in the spent exhaust)

holes in muff & air box = more lean (more air than stock)

think of "rich" in reference to air/fuel ratio as a fire - the more "liquid" you put in a fire, the COOLER it will be.
that's the goofy way i remember it.

lean = hot

so to recap:
-the bike comes EPA lean.
-more air flow means more lean.
-we need to add more fuel to cool the bike.

here's the kicker: the ECM measures the AFR (air fuel ratio) via the O2 sensor,
and you can either block the actual O2 sensor data from reaching the ECM, by putting a resistor (O2 simulator) in the O2 plug,
the DYNOJET PC3 does this on Harleys.

or you can manipulate the data the ECM sees coming.
some "piggyback" devices do this, but i can't name one.

(if the O2 sensor data reaches the ECM, the ECM will see the bike as going too rich, and will lean it out again by modifying the injector pulse width - that's how long the injector stays open, which is expressed as "duty cycle" - a percent of time,say 50% )

what fuel management products are out there for the 950, since it is so new?
 

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we drilled the air box (using the Door Deadbolt installation kit holesaw)

and drilled the muffler using a 1 1/2 bi-metal hole saw (Lowes, Ace hardware, Home Depot)

and we took a long ride, and the wife is frying.
the back of her left thigh is on fire.
there is a little plastic scoop that catches air and blows it on the back of the rear cylinder head,
and we thought that air was coming out from there onto the back of her thigh, so we pulled that part of, and that seemed to help her thigh.



lean = hot
rich = cooler



what fuel management products are out there for the 950, since it is so new?
Cobra makes one that works well. I had one on my C50 and was very pleased with the performance. Check it out here, scroll to the bottom of the page of the below link.

http://www.fi2000r.com/page.php?page=51
 

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would you guess the heat is due more to the hole in the airbox than in the exhaust, vise versa, or just the combo of both?
It's due to more holes in the airbox, the minor mod done to the exhaust won't lean out the mixture to the point where the ECU won't compensate through self re-mapping based on the data sent to it by the O2 sensor. Air flow is controlled by the air box, air filter and air filter cover and monitored by the Intake Air Pressure Sensor and the Air Temperature Sensor, modification to any of those items will allow more air to enter the combustion chamber causing a lean-out condition. A fuel management unit is highly recommended if an air filter/airbox is modified because the sensors may not be operating within specified parameters. Cobra recommends the use of the Closed Loop Module 92-1775CL or 92-1775CL-50 if your motorcycle will continue use of the Oxygen Sensors in your exhaust System.
 

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we drilled the air box (using the Door Deadbolt installation kit holesaw)

and drilled the muffler using a 1 1/2 bi-metal hole saw (Lowes, Ace hardware, Home Depot)and we took a long ride, and the wife is frying the back of her left thigh is on fire.
there is a little plastic scoop that catches air and blows it on the back of the rear cylinder head,
and we thought that air was coming out from there onto the back of her thigh, so we pulled that part of, and that seemed to help her thigh.
This engine has an engine temperature sensor, so if the engine warning light comes on it's propably because the rear cylinder is overheating in which case to promote better cooling you should reinstall the the "scoop" that you removed. Food for thought.
 
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