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I have cobra 2-1 slip in and flashed ecu. I was wondering if a k&n filter is enough or if a cobra powerflow would significantly help performance? I sometimes feel like passing uphill can be a struggle. But maybe its just because im not using high enough rpms
 

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any aftermarket air intake is going to give you more air to your fuel/air mix over stock. the cobra powerflo intake system already has a K&N filter in it. if you're wanting to add a K&N filter to your stock air intake system, you might see some improvement but the stock box housing still limits how much air gets collected and funneled into the engine versus any aftermarket housing.

 

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I just changed out my exhaust, air intake, and Fuel mgmt on my 950T.

First let me say my "stock" setup had the stock pipes' baffles drilled out. The stock intake had a K & N filter. No fuel management. I got tons of backfire on deceleration with this setup. That setup had all the power you would want and then some. But it didn't have the sound I wanted.

So I put Cobra Speedster Slashdowns on first .(yes they fit great on the 950 tourer despite what Cobra says). Now the sound was right.
Got the Cobra Powerflo intake in a few days later and installed it. Unfortunately I noticed NO difference in the sound or performance. Pretty disappointed in that. Basically spent $250 for nothing.
Next I added the Cobra Fi2000 fuel management module ( a real PIA to install) and the backfiring went away.

In all honesty now that all three components are installed I noticed a slight decrease in performance. Nothing earth shattering. I actually like it somewhat. The bike is not as squirrely as before. Before I barely rolled the throttle and I thought it was going to pop a wheely. On deceleration, if I rolled off the throttle too quick it was like I slammed the brakes on. Now with the fuel management installed that has all smoothed out somewhat.

I think the stock 2 into 1 exhaust does add to the performance of the bike.

If you want to keep your stock exhaust & intake, but beef up your performance, then drill the baffles out of your exhaust and put a K & N filter on and you will see a nice improvement. It also sounds better and isn't too loud.
 

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something important has been left unsaid here

if you modify the exhaust or the air intake and do nothing else, you have not increased the HP of your engine

all you have done is make the throttle more sensitive - when you crack the throttle open more air will get sucked in

but it will be the same as if you had twisted the throttle further before you changed anything

to get more HP you need more air and more fuel - laws of physics remain in effect

to get more fuel on a carbed bike you need bigger jets and you need to back the PMscrews out some

to get more fuel on all Yamaha fuel injected bikes you need a power commander or you need to have your stock ECM flashed (reprogrammed) to tell the injectors to dump more fuel for any given throttle twist. Need to point out, the fuel injection system on all cars, and on Harley and BMW bikes WILL adjust over time for changes to the intake and exhaust and fuel octane. The fuel injection system used on yamaha bikes is "open loop" and it does not adapt to those changes by itself.

if you dont change the fuel delivery all you have done is make the engine run lean. Eventually it will burn your valve edges and they will leak, and you can burn holes thru the tops of your pistons into the crankcase if you ride the engine really hard, in both cases your engine is toast.
 

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something important has been left unsaid here

if you modify the exhaust or the air intake and do nothing else, you have not increased the HP of your engine

all you have done is make the throttle more sensitive - when you crack the throttle open more air will get sucked in

but it will be the same as if you had twisted the throttle further before you changed anything

to get more HP you need more air and more fuel - laws of physics remain in effect

to get more fuel on a carbed bike you need bigger jets and you need to back the PMscrews out some

to get more fuel on all Yamaha fuel injected bikes you need a power commander or you need to have your stock ECM flashed (reprogrammed) to tell the injectors to dump more fuel for any given throttle twist. Need to point out, the fuel injection system on all cars, and on Harley and BMW bikes WILL adjust over time for changes to the intake and exhaust and fuel octane. The fuel injection system used on yamaha bikes is "open loop" and it does not adapt to those changes by itself.

if you dont change the fuel delivery all you have done is make the engine run lean. Eventually it will burn your valve edges and they will leak, and you can burn holes thru the tops of your pistons into the crankcase if you ride the engine really hard, in both cases your engine is toast.

So I have a V/H slip on and a stock air box with K and N filter on right now. It pops and bangs like crazy on a decel. Are you saying that eventual this will kill my engine?
If I do the Ivans tune obviously this will fix that, but will I still need the fuel management?
 

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the Ivans tune remaps the ECM to give the mixture more fuel - its a one-time adjustment and you get what you get

a power commander (fuel management module) lets you do something similar, but it has knobs or a way you can adjust it yourself, ride the bike, turn it up a bit, change the mapping for low throttle and high throttle... it allows you to tweak it till the bike runs the way you want.

how much damage running lean will cause depends on how hard you ride the bike. If you are just puttering around and running lean to get better mileage, you will see your spark plugs turning white and somewhat burnt away

if you ride it hard and fast, then yes, running lean will cause the valve and piston damage

normally when you modify the intake and exhaust you push it a little bit to the rich side, because you dont have all the equipment they had at the factory to set the fuel/air mixture perfectly, so its best to err on the side of running too rich.
 

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I was thinking the same. ECU is flashed to settings prior to adding Cobra power pro intake. So yeah you won't get the performance you could get....I have the fi2000 so I can manually tweak as I make changes.
....God only know's I make plenty of them!
 
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