PCIII cures all ills!!!!!! Well, almost

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Last Chance

Well-known member
Joined
Aug 26, 2006
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Location
Boise, Idaho
:yahoo: :yahoo: :yahoo: :yahoo: :rolleyes: :D :yahoo: :yahoo:

What follows is a long drink of cool water for me. So, if it's in the wrong forum, or a duplicate thread then just deal with it. :dribble: :blink: :p But it's been a long, hard, EXPENSIVE two months since I bought my unblemished, only slightly used (700 miles. Now 3200 miles) So, I'm celebrating. Sue me. :D :D :yahoo: B) :rolleyes: :) B) B) B)

Man oh man, what an improvement. I’ve just installed a PCIII on my 2006 FJR 1300A. Now, I love this bike but I’ve had serious issues with the herky-jerky throttle coming off idle. It was most dangerous during slow, parking lot maneuvers. In fact, I bought it new and when I test-drove it I noticed it had a real bad tendency to “kill” when starting off from stop signs/lights. I wrote it off to inexperience with the clutch, etc. Within the first 2 weeks of ownership it stalled 3 times while I was making slow, short radius 180 degree turns. Each time it stalled about a third of the way around just as I was getting well leaned over. The result was a “tip-over” each time causing great anguish/embarrassment, etc. Not to mention scratching up my almost new FJR without a scratch on it when I purchased it.

So, being a person with short appendages (arms and legs) and being almost a seasoned senior citizen I had a multitude of problems with the bike. Throttle spring too strong, needed more rise and pullback and needed a lower seat or longer legs, etc. But the thing I needed most was to smooth out the herky/jerky throttle coming off of idle. The driveline lash was also annoying but a direct result of the throttle problem.

I did the spring mod, removed any slack in throttle cable and did the Barbarian mod. I put grip puppies on because there was also a lot of vibration coming through the grips, especially above 4-5,000 rpm’s All this helped but didn’t eliminate the problems. I also noticed very definite “surging” at freeway speeds.

When one starts to add up all the “little problems” I was having, it started to make quite a long list. Oh yeah and I want a bigger windshield too!

Well, I decided my next mod was going to have to be the PCIII. The reviews and reports by those putting one on were very positive, especially on the 2006. Well, just installed it and took it for ride along the same route of my daily commute. I figured I would “notice” any differences or improvements (or lack thereof) along that route. It also encompassed city stop and go driving as well as high speed freeway driving, with frequent changes in throttle.

Well, here are my first impressions:

1. The herky-jerky throttle coming off idle is gone! I couldn’t make it stall on startup even when I tried. The throttle is very precise and can be applied in miniscule increments. I can start up, let the clutch out more rapidly, to the point of the engine rattling because of being lugged…and still not stall the engine. It is a joy to use. It will take me a while before I “trust” starting up from a stop without “blipping the throttle” to get the rpms up. But it doesn’t seem necessary now.

2. The buzz! What happened to the buzz? Normally I have to engage the “Vista Cruise lock within 15 minutes of starting my commute. Thereafter every 5 minutes or so was necessary to keep my right hand from going completely numb. On this round trip to my work location back home, about 50 miles, I only engaged the lock a few times, and then only as a “precaution”. I didn’t want a “numb” right hand while negotiating certain freeway interchanges. My impression is that the buzz is much more subdued and less bothersome. Maybe I won’t need that expensive triple tree and risers after all. Or, at least it can wait till I’m doing more touring, rather than commuting.

3. My fuel economy seems to be better. I had run the tank down to make it easier to take it off. Burning off the fuel was accomplished yesterday making some “high speed” runs on the interstate causing my average mpg to drop to about 27 mpg. Normally its been running around 32 mpg. I have an explanation. (Officer) In CA the average speed on the freeways starts at 70-75 and goes up from there. I sometimes use the awesome acceleration of the FJR to find a nice quiet spot amongst all those cars. This requires a lot of fuel and is fun to boot. So, I’m only averaging 31-33 mpg. On my short 50-60 mile circuit the average mpg went from the 27 mpg to 35 mpg. Quite an improvement, considering I was varying the throttle and gearing to get a feel for the changes in the way the bike ran, post PCIII. I’m anxious to see if there is any improvement commuting to work next week. My hunch is there will be.

4. The surging has gone away. When I first got the FJR I thought it was just “wind gusts” that were jerking me around. I started to get a little suspicious when I noticed that on some days there actually was no wind but it still felt like I was taking some gusts and slowing/speeding down/up (surging). I confirmed it after applying the Vista Cruise lock and the bike surged with my hand off the throttle. Noticeable especially in 4th and 5th gears at 70-75 with the lock engaged. Well, while it is not quite gone, it is greatly reduced and doesn’t “rock” me back and forth like it used to. I think a simple TBS will eliminate it completely

5. With all these improvements, I may not need risers. This is a very pleasant surprise and very welcome. The bike is most comfortable now commuting around town. I can delay any such improvement till next summer and maybe add a real cruise control for my travels after retirement.

6. Performance/acceleration seems to be the same. It is just a much smoother, well mannered machine now. I realize it might be morphing into something more like a ST1300 (dirty word), I don’t know. But the improvements are like night and day to me. I might add very welcome ones to boot.

That’s my take on it. All and all the very first thing I should have done. Well, I guess they weren’t available, so I can’t blame myself too much for “waiting this long” to do the PCIII. You guys are right, It’s the FI mapping, stupid me. Bigger grips help, but only treat the symptom. The PCIII is the cure. IMHO.

LC

 
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I'm glad you're happy but 35 mpg is terrible fuel mileage. The worst I ever saw, even including some very high speed hours in the flatlands, was about 41. If you're only getting 35 on a commute that tops out at 80-85, that seems really low to me. Didn't they make the gearing taller on the '06?

 
Maaaaaaaaaaaann Now I gotta get me one of those PC Thingies, Y'all are expensive to knw. I want pipes too
Yeah Man! Then when you put your "power-up" farkles and loud pipes on you kin tuner to yr harts kontent.

Yall know, speed kills and loud pipes save lives. Uhuh, youbetche!! :p

I like the sound of my other bike, the VTX1800C. At least it will do 0-60 in a smidge over 3 seconds.

In fact, if I decide to keep her for cruzin' the neighborhood, I think I'll put a PCIII on her, too. :clapping: :clapping: :yahoo:

 
I'm glad you're happy but 35 mpg is terrible fuel mileage. The worst I ever saw, even including some very high speed hours in the flatlands, was about 41. If you're only getting 35 on a commute that tops out at 80-85, that seems really low to me. Didn't they make the gearing taller on the '06?
My average is only 34.5 or so MPG in continuous city driving (can never seem to get it above 35 in the city- my highway is averaging 44). But everything he just posted is the reason I am considering a PCIII. Although, I have never had it stall on me, I have felt the lean surges and such. The improved fuel economy, if achieved, would be nice too! I would also like to get the full Holeshot system on this bike like I had on my Bandit, and the PCIII will allow me to transition more easily (well, except for the wallet part).

 
I'm not sure how the milage compares between stockers but my 03 got around 50 mpg in stock form and after the PCIII and properly set up on the dyno, I still get around 50mpg at normal cruise. I consider normal cruise to be 70-90 mph for most conditions. On the way to Bonneville this year we spent long periods over 100 mph and I still got well over 40 mpg. I don't knpw how close the maps are out of the box, but there is nothing like having a cood tech. dial it in on the dynojet with the right software. Good luck.

 
Excellent writeup. Thanks! You've made up my mind on adding the PC to my '06. I have all the symptoms you described except the low mileage and surging. I showing a 42 average with no surging, and that's with moderately aggressive riding. I wonder if you have another problem?

 
3. My fuel economy seems to be better. I had run the tank down to make it easier to take it off. Burning off the fuel was accomplished yesterday making some “high speed” runs on the interstate causing my average mpg to drop to about 27 mpg. Normally its been running around 32 mpg. I have an explanation. (Officer) In CA the average speed on the freeways starts at 70-75 and goes up from there. I sometimes use the awesome acceleration of the FJR to find a nice quiet spot amongst all those cars. This requires a lot of fuel and is fun to boot. So, I’m only averaging 31-33 mpg. On my short 50-60 mile circuit the average mpg went from the 27 mpg to 35 mpg. Quite an improvement, considering I was varying the throttle and gearing to get a feel for the changes in the way the bike ran, post PCIII. I’m anxious to see if there is any improvement commuting to work next week. My hunch is there will be.
I don't think you can trust the bike's fuel mileage readout once you install a PCIII. The bike's ECU calculates fuel mileage based principally on road speed, engine RPM, and injector pulse width. Now the PC-III sits between the bike's ECU and the injectors and changes the injector pulse width without the knowledge or permission of the ECU. Hence the ECU no longer knows what the actual pulse width is.

Have any of you guys who are reporting mileage in the low 30's or around 50 every cross-checked the average MPG reported by the bike with the actual MPG calculated from miles ridden and the gallons put in at fillups? It would be interesting to do that for a couple of tanks before and after installing a PCIII.

-Uwe-

 
the average MPG reported by the bike
:huh:

I have an '04. Don't think it has mpg display. My numbers come from tracking odometer miles vs. gallons at fill up for a bunch of consecutive tanks during a cross country run. Best mileage happened at high altitudes where I expect the ecu senses the lower manifold pressure and cuts back on fuel. Worst was on some 90-120 stretches crossing the corn and cow country. Days spent running mixed roads at 60-90 were average for the trip, around 45.

I've never checked it during daily commuting or local twisty strafing but it probably drops a bit since my commute is less than 10 miles so lots of time running rich probably before its thoroughly warmed up and I spend more time in lower gears and higher rpms in the mountains north of Atlanta.

 
35 mpg isn't that bad commuting and using the so-called gas they sell to us in Kalifornia!

When you go out of state and can put some good gas in her the mpg will jump 5 mpg!

 
3. My fuel economy seems to be better. I had run the tank down to make it easier to take it off. Burning off the fuel was accomplished yesterday making some “high speed” runs on the interstate causing my average mpg to drop to about 27 mpg. Normally its been running around 32 mpg. I have an explanation. (Officer) In CA the average speed on the freeways starts at 70-75 and goes up from there. I sometimes use the awesome acceleration of the FJR to find a nice quiet spot amongst all those cars. This requires a lot of fuel and is fun to boot. So, I’m only averaging 31-33 mpg. On my short 50-60 mile circuit the average mpg went from the 27 mpg to 35 mpg. Quite an improvement, considering I was varying the throttle and gearing to get a feel for the changes in the way the bike ran, post PCIII. I’m anxious to see if there is any improvement commuting to work next week. My hunch is there will be.
I don't think you can trust the bike's fuel mileage readout once you install a PCIII. The bike's ECU calculates fuel mileage based principally on road speed, engine RPM, and injector pulse width. Now the PC-III sits between the bike's ECU and the injectors and changes the injector pulse width without the knowledge or permission of the ECU. Hence the ECU no longer knows what the actual pulse width is.

Have any of you guys who are reporting mileage in the low 30's or around 50 every cross-checked the average MPG reported by the bike with the actual MPG calculated from miles ridden and the gallons put in at fillups? It would be interesting to do that for a couple of tanks before and after installing a PCIII.

-Uwe-

Good point. I'll "do the math" next week and see how it compares with the "before" average I was getting from the computer. I did average 41 mpg on a trip into the bay. Relatively high speed 75-80 mph but light traffic that day. Also this bike isn't really broken in yet as I only have a little over 3,000 miles on it. Ditto on the "special CA gas formulation". Plus we get to pay 25-50 cents more per gallon. Gotta love CA!

I may get a chance to go riding locally with some friends from work, Sunday. I'm anxious to see if my first impression are correct about the improvements.

 
It’s the FI mapping, stupid me. Bigger grips help, but only treat the symptom. The PCIII is the cure. IMHO.
Bingo! While the throttle pulley may exacerbate the problem, based on how you all described the symptoms it always seemed to me that the FI mapping was the culprit. (Much like it was on my 04) While I don't think we can say "case closed" quite yet, it sure is encouraging that those of you installing the PCIII are reporting such good results. It's just too damn bad Yammie's stock fuel injection mapping is so piss poor right out of the box.

As for fuel mileage, I think your smoking something funny! :lol:

Theorhetically, the PCIII should always decrease fuel mileage. With the PCIII you are richening up the mixture - adding more gas for better drivability. More gas used = less fuel mileage. I anal-retentively check my fuel mileage on every fill-up, keeping a little log book. My fuel mileage decreased approximately 10-15% after adding the PCIII. From high 40s to low 40s.

So take some close measurements, because I would think it impossible for the PCIII to increase fuel mileage, or even result in no change.

Glad to here that you found the solution to your problems and that it has transformed your FJR. Great news for you, and hopefully for others out there experiencing the same problems.

 
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Sounds like that & the pulley mod would be an awesome pair. The FI mapping improvement sounds Great! There goes more money out for me....

 
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I would think it impossible for the PCIII to increase fuel mileage, or even result in no change.
Since we can be pretty sure the PCIII richens up the mixture at small throttle openings and below 4000 rpm, I'd consider it unlikely, but it's certainly not impossible. The PCIII is definitely *capable* of making the mixture leaner as well as richer. Whether it actually might do so under some conditions is gonna be difficult to tell without logging the actual injector pulse width or an exhaust gas analyzer.

FWIW, if you install a PCIII and don't disconnect the oxygen sensor, I would expect the ECU to report higher MPG. Why? The PCIII tries to richen up the mixture by increasing the injector pulse width. The ECU sees the rich mixture at the oxygen sensor and tries to compensate by decreasing the injector pulse width. Ergo, the ECU thinks you're flowing less fuel that you really are.

If you install a PCIII and do disconnect the oxygen sensor, it all depends on what the ECU's fall-back programming is like. All ECUs that use oxygen sensors as feedback elements have some sort of fall-back programming in case the oxygen sensor fails.

Which actually brings up the question: Does disconnecting the oxygen sensor not result in the ECU throwing some sort of error code? And how does disconnecting the sensor affect the "driveability" on an otherwise stock bike?

-Uwe-

 
Maaaaaaaaaaaann Now I gotta get me one of those PC Thingies, Y'all are expensive to knw. I want pipes too
Just a line to inform you that you have the right idea. I installed the complete holeshot system (expensive) on my 2003 with 6K on it. All the jerks and lean surging went completely away. Dale sent me the map that goes with it also. Mileage went down a couple notches but the smoothness and power are great. Sound is mellow, not really loud. Go for it..........ps: a plus is reduction in heat coming up from the cat.conv. . No cooking at stop lights any more. :)

 
Which actually brings up the question: Does disconnecting the oxygen sensor not result in the ECU throwing some sort of error code? And how does disconnecting the sensor affect the "driveability" on an otherwise stock bike?
If your bike is stock, leave the O2 sensor along. Do not disconnect.

If you install a PC-IIIusb, you DO disconnect the O2 sensor, and leave it unplugged. The ECU will not care, nor will it display any error codes.

Here's how: FJRTech: Disconnecting the O2 Sensor

Note that starting on the 2006 model, the connector you see in the FJRTech article is black, vice gray like the Gen I bikes have.

 
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Warchild,

I'm new to the FJR as this '06 is my first. I'm really glad to have found this site & see the time you have spent writing up & posting top notch information, Thank You for helping cut my learning curve on this bikes maintenance & upgrades...

Robert

 
I think it would be interesting to see what happens if you take a 05 computer and plug it into a 06 bike. If all the jerking and stuff goes away yamaha has a problem and needs to pony up for some faulty puters. My 05 has never had any of these problems and I get 47mpg on average. If I get any more hp I wont be able to afford the number of rear tires I would burn through in a year.

 
Man oh man, what an improvement. I’ve just installed a PCIII on my 2006 FJR 1300A. Now, I love this bike but I’ve had serious issues with the herky-jerky throttle coming off idle. It was most dangerous during slow, parking lot maneuvers. In fact, I bought it new and when I test-drove it I noticed it had a real bad tendency to “kill” when starting off from stop signs/lights. I wrote it off to inexperience with the clutch, etc. Within the first 2 weeks of ownership it stalled 3 times while I was making slow, short radius 180 degree turns. Each time it stalled about a third of the way around just as I was getting well leaned over. The result was a “tip-over” each time causing great anguish/embarrassment, etc. Not to mention scratching up my almost new FJR without a scratch on it when I purchased it.
Hey Last Chance,

Great review!!! The PCIII is the best farkle I've put on my 06A. I've put about 500 miles on it now and I couldn't be happier. I haven't checked the mileage difference and really could care less. If I'm getting worse mileage...BFD!!!

 
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