Power Commander PC-3 & Remus Exhaust setup

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HaulinAshe

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Surprisingly, I get asked fairly often about my PC-3 map/setup using the Remus exhaust. There must be more Remus-flavored koolaid drinkers than I realize.

I have the exact same setup on both my 2006 and 2007 FJRs.

* PC-3 with Power Commander's stock map (Stock Exhaust, Stock Air Filter, O2 sensor disconnected)

* My O2 Sensor is NOT disconnected (see below for explanation)

* Remus Titanium Hexacone exhausts (they bring out the inner-Harley in me, money I did not have-spent on something I did not need. But I do LOVE my Remus!!!)

* Stock/OEM paper air filter, no modifications to the airbox

I prefer to run the Stock Exhaust, Stock Air Filter PC-3 map, but I leave the O2 sensor connected. This allows the ECU to compensate against overly rich conditions when running along at a steady throttle (slab, cruising etc.). If you happen to ride a very long/flat stretch of highway, for a very long time, with the throttle locked in one position (using a mechanical throttle lock) the ECU will generate a CHECK ENGINE light and log an O2 SENSOR OUT OF RANGE error code. The error light goes out the moment you touch the throttle to make any change. It's a rare and special condition that can only be created in extremely flat terrain, and it does absolutely no harm to the engine.

The advantage of leaving the O2 sensor connected is better highway fuel mileage without any compromise during "performance riding". The ECU reacts very little to O2 feedback during rapid changes like mountain twisties. You will lose less Highway MPG (about 2 mpg) by leaving the O2 sensor connected. Remember the PC-3 costs you MPG versus bone stock.

As for my choice of paper/OEM air filter... I learned my lesson long ago with a hord of throttle body issues related to air filter oil leaving the re-usable filter and gumming the throttle bodies. I will not go there again. It's personal choice and not up for discussion. I made my choice.

Overall, my setups are based on simplicity, predictability and the free admission that I can't remember the last time I reached for more power than the FJR could deliver. Maybe 2-up fully-loaded chasing another solo-unloaded bike. But that's not a fair fight anyway, because the GF is going to throw stuff at them in the next corner.

:D

 
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Good info.

I had the same set up except I did disconnect the O2 sensor as Dynojet tells you to do. But didn't understand why. I also ran Wally's smoothness map the Useless pickles reworked for the Gen II's. The set up worked great.

I too love the sound of the Remus cans. Great ear candy! :)

I have changed my set up some, I went the the PCV with autotune and their Os sensor hooked up. This is allow the use of two maps to toggle between for towing the trailer. I have yet to hook up the switch to make that feature active.

 
FWIW (maybe not much) I'm pretty sure that this only applies to the SECOND Gens ECUs.

I've been running a PCIII with a pretty darned rich fuel map and the O2 disco'd for several years.

Never once seen any CEL even though I know that I am well on the rich side of stoichiometricity.

When I do reconnect the O2, my fueling issues (lean surging) continue, so I leave it disconnected.

 
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Do you guys normally run with the removable baffles in or out? Are they annoyingly loud on long trips with the baffles out? Any performance difference?

Thanks!

Phil

 
This allows the ECU to compensate against overly rich conditions when running along at a steady throttle (slab, cruising etc.). If you happen to ride a very long/flat stretch of highway, for a very long time, with the throttle locked in one position (using a mechanical throttle lock) the ECU will generate a CHECK ENGINE light and log an O2 SENSOR OUT OF RANGE error code. The error light goes out the moment you touch the throttle to make any change. It's a rare and special condition that can only be created in extremely flat terrain, and it does absolutely no harm to the engine.
Have you made an attempt to correct that? I'm betting that if you just backed off the fuel at the RPM/TPS numbers you cruise at, it will eliminate that fault and not hurt your performance one bit. You could do it in small increments until it cleared up. I agree that you're not hurting anything, except maybe your mileage a little.

Joe

 
Have you made an attempt to correct that? I'm betting that if you just backed off the fuel at the RPM/TPS numbers you cruise at, it will eliminate that fault and not hurt your performance one bit. You could do it in small increments until it cleared up. I agree that you're not hurting anything, except maybe your mileage a little.
I did try tweaking the fuel a bit leaner in that range. It doesn't take much change before it becomes noticeable in the small, off-idle, bursts of throttle. That's why I decided to leave the map as-is and deal with the out of range error a couple times each year. It's really no problem, as long as you remember why the light comes on.

 
FWIW (maybe not much) I'm pretty sure that this only applies to the SECOND Gens ECUs.

I've been running a PCIII with a pretty darned rich fuel map and the O2 disco'd for several years.

Never once seen any CEL even though I know that I am well on the rich side of stoichiometricity.

When I do reconnect the O2, my fueling issues (lean surging) continue, so I leave it disconnected.
Agreed. That's why I specifically listed my 2006 and 2007 year model bikes. Gen-I is a completely different animal. Although, I do know of one 2003 model that uses a toggle switch setup to enable/disable the O2 sensor with a PC-III setup. He says it works well.

 
Have you made an attempt to correct that? I'm betting that if you just backed off the fuel at the RPM/TPS numbers you cruise at, it will eliminate that fault and not hurt your performance one bit. You could do it in small increments until it cleared up. I agree that you're not hurting anything, except maybe your mileage a little.
I did try tweaking the fuel a bit leaner in that range. It doesn't take much change before it becomes noticeable in the small, off-idle, bursts of throttle. That's why I decided to leave the map as-is and deal with the out of range error a couple times each year. It's really no problem, as long as you remember why the light comes on.
Cool. I sure wish there was a scan tool we could connect to our bikes to see the fuel trims, and lots of other data. Doing diagnostics on cars has spoiled me in that regard.

Joe

 
Do you guys normally run with the removable baffles in or out? Are they annoyingly loud on long trips with the baffles out? Any performance difference?
I realized this morning that I forgot to answer that question.

Mine are in too.

The noise level increases just enough to be annoying for a passenger over the course of a day. But the biggest difference I notice is a marked decrease in low-end torque, with no discernible increase in top-end performance.

 
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Do you guys normally run with the removable baffles in or out? Are they annoyingly loud on long trips with the baffles out? Any performance difference?
I realized this morning that I forgot to answer that question.

Mine are in too.

The noise level increases just enough to be annoying for a passenger over the course of a day. But the biggest difference I notice is a marked decrease in low-end torque :unsure: , with no discernible increase in top-end performance.
I guess it is style over function argument!

I moved over to the PC V + Autotune from a PCIII. Its allowed my bike to achieve high mpg and no snatchy feel on throttle movement.

Andy

 
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Do you guys normally run with the removable baffles in or out? Are they annoyingly loud on long trips with the baffles out? Any performance difference?
I realized this morning that I forgot to answer that question.

Mine are in too.

The noise level increases just enough to be annoying for a passenger over the course of a day. But the biggest difference I notice is a marked decrease in low-end torque, with no discernible increase in top-end performance.
My Muzzy full header system also gave a low-end torque loss unfortunately, just between 3-4k rpm. I can't remember if the bike had a flat spot there stock but it does have one now.

 
But the biggest difference I notice is a marked decrease in low-end torque, with no discernible increase in top-end performance.
That's interesting. When I did a bunch of dyno runs a while back, I saw no significant difference between baffles in vs. baffles out. My runs started right around 3000 RPM. Did you feel the decrease in torque below 3000?

edit: that was with a Holeshot header and a hacked up air box, so the effect of the baffles could be different.

 
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But the biggest difference I notice is a marked decrease in low-end torque, with no discernible increase in top-end performance.
That's interesting. When I did a bunch of dyno runs a while back, I saw no significant difference between baffles in vs. baffles out. My runs started right around 3000 RPM. Did you feel the decrease in torque below 3000?

edit: that was with a Holeshot header and a hacked up air box, so the effect of the baffles could be different.
Yes, I recall the noticeable difference being below 3,500.

 
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