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Discussion Starter #1
Link to Loyd'z IAV

Can someone help me understand better what this does? I get the gist from the description, but maybe some definitions would help. What is the "tip in"? And what exactly is Idle Air? I would think it would be the air intake when the bike is idling, but the description implies that adjusting this valve has an affect on the air intake as you open the throttle.

Also, what does this valve do in relation to what Loyd'z Power Commander does? Is it that this controls air and the PC controls fuel?

Lastly, why would you want to limit the air? I thought I just opened up my airbox and exhaust so that I could get MORE air moving through the engine? And I thought the PC would allow me to increase the fuel in the mixture to accommodate the increase of air.

Sorry for all the questions. I'm probably missing something dumb. I know you guys can help school me. :) Thanks!
 

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Although I don't own an IAV, I think I understand what it's targetting in contrast to the Power Commander. What it's really focused on is the throttle transition point between idle and throttling on the gas.

Some of the Victorys (including mine) have a particularly abrupt transition making it very hard to hold the bike at a low throttle position, particularly in 1st gear. This allows you to smooth that out. In addition, a lot of decel popping happens when you come off the throttle and transition to idle due to this abrupt transition which causes a lean condition and results in the popping.

The Power Commander is targetted at getting a good fuel mixture and optimizing your engine power curve based on throttle position and rpm..primarily while you're on the throttle and riding. There are ways in the PC to address the idle situation by tweaking the fuel settings at the 0% throttle position throughout rpm ranges. I don't do that personally, but there are some that do and are pretty happy with their results.

I suppose I'd invest in one if I was more bothered by this idle transition but I'm not.
 

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Not sure on a bike, but on a car the IAV lets enough air bypass the throttle plates to maintain the desired idle speed. If youy've ever had a car that idles way low then jumps way high then repeats, Its a sticking IAV or TBV (throttle bypass valve).
 

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Discussion Starter #5
I posted that same link in my orginal post and said, "I get the gist from the description..."
I have read what it says and I was hoping to get some additional info. Sorry if they're dumb questions, but maybe with a little more info i can make the description from the site make more sense to me.
Thanks
 

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I was wondering this myself. My other bike being and FI twin race bike, I had to dig into it to really begin to understand the tuning aspect of it. The way it worked on my other bike was that the Idle was set to a small degree (about 4.5) that the valve in the throttle body would be open. This provided just enough air to keep the bike idling when the system views the throttle as closed.
Set your idle too low (2-3) and the bike would cough, hack wheeze, stumble and run like crap in low rpm's because it wasn't getting the air it needed. Most people, in response, would set their idle higher(6-7). Its produced a healthier faster idle, but If your idle is too high, the rpms would hang when you closed the throttle from the open position.....because while the throttles supposed to be closed, you still have more air rushing it seemingly from nowhere.

So working that reasoning backward, I figured this could be like an inline valve that works similar to one of those covers you see on the exhaust stacks of a semi....That lays over the top and keeps the rain and birds out, but when the exhaust needs to escape, it pushes the cover open. Perhaps this could be the reverse, when the bike requires more air, the vacuum opens the valve to let more in. The more likely scenario, it probably has a spring loaded plate that you can tweak to a degree to create an intake leak as a complimentary inlet to the airbox/throttle body and smooth out any low chugging coughing caused by the throttle plate being closed to too small a degree at idle because it was set to facilitate the open throttle fuel mixture.

Any changes it would cause at wide open throttle in higher gears where it could run super lean might be negligible probably because the bikes in closed loop at the point and adjusting the other intended intake as it gets readings from the sensors. Making the air intake valve an off the radar, complimentary mini intake that can't be automatically adjusted/stifled by the ECM/ECU. Just my theory.
 
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