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I just purchased the cobra swept exhaust in black for my 2009 custom 900 SE My question is do i need a power commander if im just swapping my exhaust it doesnt say anything about needing one But if I change my air filter also will than I neeed one ?? Please help me with a quick respond Thanks
 

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I just purchased the cobra swept exhaust in black for my 2009 custom 900 SE My question is do i need a power commander if im just swapping my exhaust it doesnt say anything about needing one But if I change my air filter also will than I neeed one ?? Please help me with a quick respond Thanks
You should be good to go, until you install an aftermarket big air cleaner. A Power Commander is an option there are other fuel controllers out there.:D
 

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You don't need it but Cobra recommends a fuel management even if you only install only the exhaust.

This is what should have come with your instructions. Don't believe they're just trying to seel you another one of their products, even other exhaust manufactures recommend it even those that don't make a fuel management.

IMPORTANT: Cobra highly recommends using a Fi2000 Fuel Management System to help eliminate
lean conditions and popping sounds.(Cobra Part# 92-1968 for 49 state models and
Part# 92-1968-50 for CA models.)
 

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No…you do not need a fuel integrator if you’ve just changed your pipes. You might need one for a higher performance motor, but the VN will be just as happy without it. In fact, I suspect that OUR motor will not run destructively lean even if you put one of the designer air breathers out there on the front end.
All a fuel integrator does is to allow you to stick a little more fuel into the hole, to compensate for the fact that more air is getting into, and out of the cylinder. Yes…I know the PC3 is a little slicker than that, since it allows you to actually reduce the fuel in the air fuel ratio until you reach a theoretical “perfect” mix….but usually, with a three pot system…like Cobra’s for example, you’re just telling the injectors to stay open a liiiiittle bit longer to allow more fuel to squirt in.
Your motor, with its new pipes can now breathe out a little more easily, but it’s still breathing in through the same itty bitty straw that is was using before you did the OEM exhaustectomy. Therefore, the added fuel might actually result in having an overly rich mixture, which really isn’t too bad a thing (unless you happen to be a spark plug) but it’s all a waste of money (and fuel) IMHO.

All this changes of course, if you have a dresser drawer full of drag slips, and you’re looking to shave the last 10,000ths of a second off of your ¼-mile time – in which case you’re going to want to do a lot more than putting pipes on your motorcycle…:D

JMHO...:cool:
 

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No, especially not with the 900. My understanding is that it becomes more of a potential issue in the higher cc models.
 

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Cobra puts that "recommends" in for two reasons. 1st, never hurts to sell a product. 2nd, ALWAYS CYA. You could be that one guy whose bike is different from the rest of us who have altered our exhausts. ALWAYS check your plugs after making an air flow modification to your engine to verify that you're not running rich or more importantly, lean. If they sold it to you, told you it wasn't necessary and you're the lucky bike owner, you could conceivably go back to them and ask for a new motor. Most people do not need a processor, but check to make sure you don't either. It's REAL easy to do and mr Google will look up a picture chart for you to compare your plugs with.

Not mentioned yet, Marble your reed valve line when you make the swap. Your motor feeds air into the exhaust to help the catalytic converters in the front of your mufflers burn the excess fuel off. When you swap exhaust you will not have these converters nor will you have the benefits of a full muffler to quite down the pops you actually have now. So without the marbling you will have pops. The correct hose is the upper right/front hose on the back of the OEM air filter housing. Stuff either a Marble(where this procedure gets its name) or a Yellow (12-14 gauge)wingless wirenut into the hose. Either will plug it so that no air can come through. If you need to take the wirenut out you can stick a piece of house wiring into it, twist a couple times and pull it out.

Also, when you put the new pipes on, get some new crush gaskets and torque them on properly in steps. The torque value is 14 ft lbs. Line the pipe up, press it firmly on the jug with the new gasket in place and screw the nuts on till they both just touch and sit square. Now tighten them each to 5 ft lbs, then 10 ft lbs and finally 14 ft lbs. Improper tightening will cause them to crease and let air into the exhaust that way, causing popping again. Ride it a couple times or put about 100 miles on it, then when it cools, check the torque again. The heat cycles will expand and contract things loosening your nuts. Once will probably take care of it, the first couple heat cycles are where it happens the most, but check it again later.

I've had a round of talk with a guy last month who said "It sucks air? BS" or something like that and we had to go over the fact that it does suck air. As the exhaust pulse goes by and the valve is shut, the exhaust doesn't make it out of the pipe before it stops expanding, this causes a negative pressure and is where the reads let the extra air in. Then the next pulse comes out of the engine which snaps the reed shut and shoves all that hot gas into the mass of just fed air and they both travel down to the catalytics where as much as possible gets converted into water vapor I believe (isn't that what the catalytics convert too?)

Anyways, Marble your Reeds. Correctly torque your new gaskets, and most importantly CHECK YOUR PLUGS. You should be right as rain and enjoying your new pipes.
 
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