Power Commander - WTF?

[jwhite518]

Edited to add context

I own a used 05 that I bought from a great guy I met on the forum. The bike was meticulously maintained and nicely farkled. All work was done at a Yamaha shop. (Though I have some quibbles about the additional wiring for electronica - no fuses!) One of the farkles was a Power Commander III. The PO told me that it was running the 001 map from Dynajet. The O2 sensor was disconnected. The exhaust and air filter are stock. The Barbarian mod has not been done.

Since buying the bike I've suspected I wasn't getting the mileage I should have. The odo was counting backwards at anywhere between 150 and 175 miles. I thought the thing was supposed to have a longer range than that. That's why I posted the "what's your range?" poll last week. I hadn't actually bothered computing my mpg but I had a gut feeling it sucked.

Last Saturday I rode 1100 miles and did calculate my mpg at each fillup. My first tank I got 28.5mpg, second tank was 31mpg. As the day went on the mileage slowly improved, and my final overall mileage for the ride was 35. It was suggested to me that my PCIII was the root of my mileage issue, so this morning I disconnected the PCIII wire harness and reconnected the O2 sensor.

As far as I can tell, just from riding 35 miles to work over a combination of freeway and city streets, there is absolutely no difference in throttle response or performance. The bike feels identical. So I ask you - Why do people put these things on their bikes?

 

[S76]

Did you disconnect the O2 sensor?

 

[RiderCoach Lar]

I'm going to assume you didn't put it on the bike or you'd not be asking the question. So you may not know if it was installed correctly and the oxygen sensor was disconnected. And if you didn't put it on the bike, you probably don't know which map it's running or why. Assuming your unusually crappy gas mileage is exclusively a result of the PCIII (not likely since there's 'absolutely no difference in throttle response or performance'), you could be running the wrong map for your situation.

There's been volumes of posts regarding the benefits of using a PCIII. Most install them (with great success) to smoothen out twitchy or abrupt throttles. Some install them in conjunction with aftermarket exhausts since less restrictive exhausts tend to magnify the effects of the already-too-lean engine. The (search-able) feedback from those who have installed one and found great benefits of doing so is a bit overwhelming. In all fairness, however, there has also been a hand full of guys who have no problem at all or feel their bikes run well enough without them. Sounds like you might be one of them

 

[HotRodZilla]

How is your bike set up? Aftermarket pipes and air filter, or is that stuff still stock? As RCL stated, it doesn't sound like you know much about the PC's set up. Also, has your mileage improved since you disconnected it? If not, there is definatly something other than the PC causing your issue. If it did, your PC may be feeding too much fuel due to a bad map. Were any accessories taken off when you bought it? Like, did it have aftermarket pipes that the original owner kept, so he put the OEM cans back on it?

Personally, I have no complaints about how my bikes runs stock. It does not vibrate, is not abrupt, and doesn't seemt to need aftermarket help. Eventually, I will put aftermarket exhaust on it and will add a PC to adjust for flow since the ECU cannot adjust for flow, only altitude. 5 minutes on a lap-top will fix a mapping issue.

Me thinks we need more info.

 

[Silent]

If you want the install checked over, give a holler

 

[jwhite518]

My bike has stock pipes and air filter. The 02 sensor was disconnected. PO said it was running the 001 map, not the smoothness map. When I disco'd the PC wire harness I also reconnected the 02 sensor. I don't know if mileage has improved, I haven't drained a tank yet.

 

[JimLor]

I've got an 05 and installed the PC and disconnected the O2 sensor. I've run the Wally smooth and the PC stock maps. The Wally gave me noticeably less gas mileage, say 35 mpg or so. I went back to the stock map and average about 42mpg. You can get the maps around here somewhere or from the PC site. I'd reinstall the stock map w/O2 sensor disconnected. You might also check that what was disconnected was in fact the O2 sensor and not a similar connector.

 

[Fred W]

On an '05 you will not feel a huge difference in the roll-on smoothness IMO. What I installed my PCIII for was the freeking unbearable lean surge that occurs between 3000 and 5000 rpm when on steady throttle. I started out using the maps provided by the PCIII guys, but they sucked. I subsequently received (via email) and loaded a custom map that was generated on another 05 FJR Forumite's bike on a dyno for a bike '(like mine) with stock pipes and intake. To me, the difference was tangible and satisfying.

I was ready to go mess with dynos to get a good map, but the one I got works well enough for me not to want to spend the money and time at the dyno shop, possibly not getting anything better.

Lemme know if you want a copy and I will email it to you.

Oh, I get about 42-45 mpg, except in West Virgina at EOM, in which case it drops to 35. But I know why that is...

 

[spinblue]

Would the Barbarian mod and possible adjustments there have a possible bearing here?

 

[v65]

Edited to add context
I own a used 05 that I bought from a great guy I met on the forum. The bike was meticulously maintained and nicely farkled. All work was done at a Yamaha shop. (Though I have some quibbles about the additional wiring for electronica - no fuses!) One of the farkles was a Power Commander III. The PO told me that it was running the 001 map from Dynajet. The O2 sensor was disconnected. The exhaust and air filter are stock.

Since buying the bike I've suspected I wasn't getting the mileage I should have. The odo was counting backwards at anywhere between 150 and 175 miles. I thought the thing was supposed to have a longer range than that. That's why I posted the "what's your range?" poll last week. I hadn't actually bothered computing my mpg but I had a gut feeling it sucked.

Last Saturday I rode 1100 miles and did calculate my mpg at each fillup. My first tank I got 28.5mpg, second tank was 31mpg. As the day went on the mileage slowly improved, and my final overall mileage for the ride was 35. It was suggested to me that my PCIII was the root of my mileage issue, so this morning I disconnected the PCIII wire harness and reconnected the O2 sensor.

As far as I can tell, just from riding 35 miles to work over a combination of freeway and city streets, there is absolutely no difference in throttle response or performance. The bike feels identical. So I ask you - Why do people put these things on their bikes?

I would think that if you were dumping that much gas the throttle response would improve! Anyways, any chance that a barbarian jumper mod was also done? It would be nice to know all of the variables here.

Oops, spinblue beat me to it. I gots to read better.

 

[Fred W]

That is a good question. I tried adding fuel via Barbarian Jumper Mod along with the PCIII and it was not a good thing. I never got to calculate the mileage, but it was clearly running too rich at that point.

 

[jwhite518]

Barbarian not done.

 

[Happy Dog]

Sell the PCIII. People are paying enough for them new, should be able get a return on that investment. No, I don't want to buy it--already have one and I see results when it gets tweaked at the dyno--but I have Holeshots, K&N, air box mod...

 

[Bounce]

The PC3 was mostly for addressing the low-speed/low-load throttle surge (~2500 rpm cruising in stop-and-go traffic) and to richen the mix to help address the OEM overly-lean mix that is the result of having to comply with draconion EPA requirments. hmmm richer=more fuel=less mpg. Richer also helped some people with their perception of heat (along with a little modification to the air management under the plastic).

The barbarian jumper mod doesn't "add fuel" is adjusts the CO settings and only slightly addressed the surge (but not the lean mix).

It's all been discussed at very great length. for more technical details do a search on PC3, Power Commander, heat, surge and other key words. See you in about a month when you're done studying all the data.

Before you sell the PC3, ride the bike for a month and do some local commuting on it. This time of year is too late to see if you notice the heat or not (it's a personal perception thing amongst different riders). If you then decide you don't want it, sell it.

I took mine off for my last milestone service before my YES expired on my 03. I went back to the OEM pipes and no PC3 installation. I've not put it back on again since but I'm still not selling it because I still might choose to use it. In the mean time, the last time i topped off the tank I got 51.2 mpg from simple local commuting to work (7 miles, 1-way on all surface connectors). With the PC3 I usually got something like 32 mpg. Either is better than the 13 mpg i was getting in my truck and the lowered mpg was fine given the smoother throttle response (using map 001, my custom map, or the Smoothness map).

 

[jwhite518]

The PC3 was mostly for addressing the low-speed/low-load throttle surge (~2500 rpm cruising in stop-and-go traffic) and to richen the mix to help address the OEM overly-lean mix that is the result of having to comply with draconion EPA requirments. hmmm richer=more fuel=less mpg. Richer also helped some people with their perception of heat (along with a little modification to the air management under the plastic).
The barbarian jumper mod doesn't "add fuel" is adjusts the CO settings and only slightly addressed the surge (but not the lean mix).

It's all been discussed at very great length. for more technical details do a search on PC3, Power Commander, heat, surge and other key words. See you in about a month when you're done studying all the data.

Before you sell the PC3, ride the bike for a month and do some local commuting on it. This time of year is too late to see if you notice the heat or not (it's a personal perception thing amongst different riders). If you then decide you don't want it, sell it.

I took mine off for my last milestone service before my YES expired on my 03. I went back to the OEM pipes and no PC3 installation. I've not put it back on again since but I'm still not selling it because I still might choose to use it. In the mean time, the last time i topped off the tank I got 51.2 mpg from simple local commuting to work (7 miles, 1-way on all surface connectors). With the PC3 I usually got something like 32 mpg. Either is better than the 13 mpg i was getting in my truck and the lowered mpg was fine given the smoother throttle response (using map 001, my custom map, or the Smoothness map).

Thanks, Bounce. Just the kind of input I'm looking for, minus the month long search. I'm going to keep it disconnected for now, but will leave it in place on the bike. I can always reconnect it in five minutes. The bike isn't a daily commuter, maybe 2-3 days a month. I'm not that concerned with with low speed, low throttle behavior. Its main role is for distance trips.

 

[CHRIS_D]

I too was getting really bad gas mileage using Wally's Smoothness map (about the same range as you). However as advertised the bike did run as smooth as hell!! When I took my last 500 mile trip (all highway) I was only getting around 30 MPG. To me this is totally unacceptable. Since then I been tweaking the map. So far I have found that most of the numbers are way too high then what's needed to obtain the desire smoothness. Yes this where most of fuel is being wasted. I have pretty much cut all the + #'s in half and from 3.25K to 4K I lowered the numbers even more and anything above 4K RPM was set to zero. Now my highest number is "13" which before there where numbers as high as "26".

Yes the bike is running smooth and my around town mileage has gone up 4 MPG (now close to 40 MPG). I haven't been able to test the highway mileage yet, but since now I'm essentially running the stock map (because it's set to zero above 4K mark) it should hopefully be back to the stock MPG.

 

[turbodave_98]

On my 05 I added the Power Commander USB unit. I installed it per the instructions and disconnected the O2 sensor. Only change in the bike with having the unit connected for 15k miles was a LOSS of 4 mpg. At WFO 4 after talking to another FJR buddy, it was disconnected and left on the bike, the O2 sensor was re-connected and the mpg WENT UP 5 mpg.

My 06 AE, I have not tried the unit.

 

[jwhite518]

On my 05 I added the Power Commander USB unit. I installed it per the instructions and disconnected the O2 sensor. Only change in the bike with having the unit connected for 15k miles was a LOSS of 4 mpg. At WFO 4 after talking to another FJR buddy, it was disconnected and left on the bike, the O2 sensor was re-connected and the mpg WENT UP 5 mpg.My 06 AE, I have not tried the unit.

Way to go, scarboy. Once again you are my hero.

 

[turbodave_98]

On my 05 I added the Power Commander USB unit. I installed it per the instructions and disconnected the O2 sensor. Only change in the bike with having the unit connected for 15k miles was a LOSS of 4 mpg. At WFO 4 after talking to another FJR buddy, it was disconnected and left on the bike, the O2 sensor was re-connected and the mpg WENT UP 5 mpg.My 06 AE, I have not tried the unit.

Way to go, scarboy. Once again you are my hero.

If that is true, you are in BIG, DEEP, Kimshi!! :yahoo: