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stage 1 muff..stage 1 air..can you??

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Old Mar 7, 2008 | 07:25 PM
  #1  
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Default stage 1 muff..stage 1 air..can you??

I hear that on a pre 06 FI bike you can install stage 1 mufflers OR stage 1 air cleaner with a stock ECM...I have a FI 07 RK and want to know if i can put on stage 1 exaust AND stage 1 SE air cleaner without any upgrades to the ECM...Does the 02 sensors make that possible...A PC III is in the future....
 
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Old Mar 7, 2008 | 07:31 PM
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Default RE: stage 1 muff..stage 1 air..can you??

A low restriction intake requires some kind of fuel management, be it a download from HD , PCIII, Sert, DF0 or whatever. In my honest opinion, the earlier bikes may get away with just a fuel controller like DFO for stage one BUT 06 and up where they have used very aggressive timing , an advanced unit with timing capabilities is probably wise.

Some believe mufflers only doesn't need anything but that is iffy to me since they all can use some help even box stock.

EZ
 
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Old Mar 7, 2008 | 07:49 PM
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Default RE: stage 1 muff..stage 1 air..can you??

60wt,

Your question is a little confusing, so I'll try this approach.

It makes no difference regarding the year, the motor size (883, 1200, TC88, or TC96 and up), carburated, or ECM, when you open up the breathing at both the carb/TBI (high flo air filter system) and the exhaust, you need to make some changes in the air/fuel mixture. As you are pumping more air through the engine, the amount of fuel needs to be increased to improve the efficiency of the combustable mixture in the cylinder at the time of detonation.

For carbed models, they get re-jetted oversized from stock. For ECM models, the ECM needs to be 'told' to add more fuel via the map.

If you were to make the mods that you asked about and did not, at the very least, get the Stage I download or add the PC III,over time you'll damage your motor and you'll not be happy with the performance.This is because you'll be makingan already lean EPA compliant mixture settingeven more leaner.
 
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Old Mar 7, 2008 | 10:55 PM
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Default RE: stage 1 muff..stage 1 air..can you??

ORIGINAL: flhtc07ok

60wt,

Your question is a little confusing, so I'll try this approach.

It makes no difference regarding the year, the motor size (883, 1200, TC88, or TC96 and up), carburated, or ECM, when you open up the breathing at both the carb/TBI (high flo air filter system) and the exhaust, you need to make some changes in the air/fuel mixture. As you are pumping more air through the engine, the amount of fuel needs to be increased to improve the efficiency of the combustable mixture in the cylinder at the time of detonation.

For carbed models, they get re-jetted oversized from stock. For ECM models, the ECM needs to be 'told' to add more fuel via the map.

If you were to make the mods that you asked about and did not, at the very least, get the Stage I download or add the PC III,over time you'll damage your motor and you'll not be happy with the performance.This is because you'll be makingan already lean EPA compliant mixture settingeven more leaner.
What he said +1
 
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Old Mar 8, 2008 | 07:32 AM
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Default RE: stage 1 muff..stage 1 air..can you??

Ill throw this into the mix.

Technically speaking, if the motor was to go "lean" / out of range of the O2 and the AFV in the ECM, then wouldnt the CEL come on?
In other words, you can put aftermarket exhaust and an air filter on your bike, the bike will relearn the fuel needed to maintain the 14.7 in closed loop (WHICH ISNT TOO LEAN!!! Stop saying that). IF the ECM cannot maintain perfect fuel happyness it will light up the check engine light... No light. Engine is handling the fuel... Which is what really happens...

Having said all that... I would remap just to take the heat out WHILE maintaining the 14.7 A/F ratio but correcting the timing where most of the heat comes from.

Someone correct me if im wrong. Cause if I am. My brain needs a new download also... Will a SERT plug into my ear or do I need an adaptor?
 
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Old Mar 8, 2008 | 08:23 AM
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Default RE: stage 1 muff..stage 1 air..can you??

ORIGINAL: donk_316
Someone correct me if im wrong. Cause if I am. My brain needs a new download also... Will a SERT plug into my ear or do I need an adaptor?
No problem...It will plug in your ear if you use a hammer........
 
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Old Mar 8, 2008 | 08:46 AM
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Default RE: stage 1 muff..stage 1 air..can you??

Donk, you are so wrong about 14.7 being too lean. It is.

Do you think that Harley would run these engines that lean if the EPA didn't require it?? No way!
The Harley lump is an old air cooled 2 valve pushrod design that loves fuel and is not designed as a lean burn engine like many of the more modern 4 valve liquid cooled engines out today.

Air cooled motors are cooled just as much with fuel as they are with air. Ask any pilot who flies air cooled piston aircraft how he can make an engine run cool or hot with the fuel mixture. (yes timing also but not as much)

If Harley could do it the way they wanted, they would not be running O2 sensors, they would be running them like they used to, lots of gas!

A harley engine running 14.7 will be running hot and have lazy throttle response. Give it more gas and it will be much happier. That is a fact of life with just about any motor out today. more so with the Harley motor.


 
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Old Mar 8, 2008 | 09:55 AM
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Default RE: stage 1 muff..stage 1 air..can you??

ORIGINAL: airfuel
Donk, you are so wrong about 14.7 being too lean. It is.
Do you think that Harley would run these engines that lean if the EPA didn't require it?? No way!
The Harley lump is an old air cooled 2 valve pushrod design that loves fuel and is not designed as a lean burn engine like many of the more modern 4 valve liquid cooled engines out today.
Air cooled motors are cooled just as much with fuel as they are with air. Ask any pilot who flies air cooled piston aircraft how he can make an engine run cool or hot with the fuel mixture. (yes timing also but not as much)
If Harley could do it the way they wanted, they would not be running O2 sensors, they would be running them like they used to, lots of gas!
A harley engine running 14.7 will be running hot and have lazy throttle response. Give it more gas and it will be much happier. That is a fact of life with just about any motor out today. more so with the Harley motor.
See and this is where the confusion lies...
I am not disagreeing with anything you said.

BUT

If 14.7 was truly "too lean" we would have melted pistons everywhere now wouldnt we...

You are confusing stoch 14.7 with performance.

The HD engine (or any internal combustion ENGINE running on gasoline) will run all day and night at 14.7 without a hiccup.

Now if you want a cool running motor with loads of power and snappy throttle, THEN you add more fuel to the mix.

But the engine is NOT "too lean". If it was, it would melt. Its as simple as that.

Maybe we are arguing semantics here, but I hope you see my point and that I agree totally with what your saying.
 
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Old Mar 8, 2008 | 10:41 AM
  #9  
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Default RE: stage 1 muff..stage 1 air..can you??

"Maybe we are arguing semantics here"

LOL, yes BUT whY? Bottom line, because of EPA regs made by bureaucrats without a clue, they are Too F'n LEAN , period! If an engine doesn't realize its potential because of too little fuel, it IS TFL!

EZ[sm=sorry.gif]
 
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Old Mar 8, 2008 | 10:59 AM
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Default RE: stage 1 muff..stage 1 air..can you??

Pistons would not likely melt in a too lean condition. When leaning an aircraft engine for fuel economy ( manual adjustment) and watching the exhaust temp, you will hit the peak temp and slightly enrichen it from that point. If however you keep going in the lean setting the exhaust temp will actually drop slighty before the engine shows signs of fuel starvation. Detonation with a hot piston will cause the damage and is more likely to happen in a lean setting. Full rich is recommended for max hp and best cooling under high takeoff loads. 14.7 , while it is the optimum burn, it is also the highest heat generated from the fuel. This is fine if the cooling can be controlled as in liquid, but in air cooled engines in some situations it may not be the best. Personally, I like 13.8-14.2 afr for my air cooled Harley, as fuel has a cooling effect as well in overall temps.
Ron
 
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