CO adjustment

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prshguy

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I'm working on getting rid of a surge between about 1500-2500 rpm on my 05 FJ. I've done the jumper modification and can now access my CO adjustment on the instrument panel. I've followed the directions given by others who have done this but I'm still getting the surge.

I first added 7 points to the original number for each cylinder. This didn't get rid of the surge but did seem to smooth the engine a little at cruising rpm. I then tried going to +9 points but didn't see any further improvement.

So, I have some questions:

1. Have others out there adjusted their CO levels and gotten satisfactory results?

2. How far can I go before causing myself problems.

3. Should I be seeing immediate results after an adjustment or does the computer need to learn the new settings over time?

Thanks for any help.

 
I'n not trying to pick on you , but I'm wondering if you're trying to solve the wrong problem. The FJR (mine's an '05 like yours) has a jump in power in the RPM range you describe, which I attribute to the engine "coming up on the cam" for lack of a better way to describe it. Most high performance 4 stroke motorcycle engines have a certain spot (or spots) in the RPM range where engine breathing efficiency is optimum, and you see a jump in the HP and torque curves as a result.

Is this the surge you describe? If so, I doubt you'll get rid of it by tuning the EFI settings. You'd need to adjust cam profiles or cam timing to change the way the engine breathes, and this would affect power at all rpm. Or you could shift at higher RPM so the engine stays above 3000 RPM. This is not a cruiser motor, and if you spend any significant amount of time riding the FJR at 1500-2500 rpm, you're lugging the motor and you belong in a lower gear for that speed.

Hope this helps...but if not you may consider taking it in for warranty check up. Surging is not a commonly reported problem with this engine.

 
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It helped slightly, but had nowhere near the results the PCIII did. Money well spent, as anyone here who has gotten one will attest to.

 
Windjammer, I understand what you are referrring to but this is different. Out on the open road, yes, I would not likely be in this rpm range but in the city, with stop and go, the surge is annoying. My 04 Triumph ST I just sold had very nicely calibrated fuel injection as did my K series Beemer before that. My carbureted Honda ST1100 from a couple of years back was beautifully smooth at this rpm.

So, anyway, I'd just like to get rid of this little bobble. I sync'd the TBs tonight and that helped a little. My understanding is that the PCIII will richen up the powerband and get rid of the leaness that is inherent in most of today's motorcylces, but I was really hoping to avoid that expense by playing with the baseline numbers via the dashboard.

Thanks for you input.

 
OK, I understand what you're after now. I'd describe my bike as having a somewhat abrupt response when accelerating from off-throttle to on-throttle. The twistgrip is almost a bit like a power switch. Sometimes this is kinda neat, but not coming out of a tight corner, and not navigating slow traffic.

Accourse a CV carb bike like your ST and my old Concours were smoother. The carb design caused sort of a slight "lag" in throttle response, things kinda spooled up instead of hitting like a switch.

Rad's advice might be best on this one, but I don't know. Good luck!! :)

 
I'm going to try disconnecting the battery tonight and let it sit for a while to "reset" the ECM, then just ride it with the CO set at +8. If I find I can't live with it, I think the Techlusion sounds like the most cost effective way to handle this. I'm happy with the power, so getting more oomph isn't a priority, I just like a smoothly responding throttle.

I'm still wondering how far one can go with the CO settings. Anyone tried some more agressive adjusting like +12, +15 or something like that?

Thanks again for the input.

 
Out on the open road, yes, I would not likely be in this rpm range but in the city, with stop and go, the surge is annoying.
Thanks for bringing back memories of my wonderful BMW R1150R.

Techlusion solved that problem. No hunting or surging on my FJR.

 
Not sure that leaving it unplugged will "reset" anything. I bet the EFI computer uses non-volatile memory (e.g. flash memory) to store settings, so you won't lose anything no matter how long you leave in unplugged.

I don't know this for sure, but think about it: they set the cylinder values in the factory, and then ship the bike all over the world, potentially to sit for a while before being prepped and sold. Is there even a battery in the crate while it's being shipped?

 
Disconnecting the battery won't reset the ECU. You can bump the CO settings a large amount, you are just moving farther away from the acceptable range of CO offsets determined by Yamaha's equipment. As you bump up offsets toward richer settings the only consequence will be gradually reduced drivability. As you get leaner you start to run the risk of overheating and *possibly* melting parts :eek: Because CO is set to someplace in a 'range' of acceptable offsets it is possible to move settings within this window to get smoother operation. If you set CO offsets well outside this range you will start to notice degraded operation.

It has been speculated that the CO settings have the greatest significance at or near idle and the effect diminishes as RPM goes up. I haven't seen actual proof of this but hey, that's the way it works with automotive engines, I don't see why it wouldn't be true with the 1300.

Adding a PCIII or a TI will reduce throttle abruptness and will vastly reduce or eliminate surging.

You should check/verify your TB synch after the tweaking is done.

Alan

 
apratt  Posted on Feb 2 2006, 04:06 PMIs there even a battery in the crate while it's being shipped?
Yes, there was in mine. In fact, it's mounted in the bike but the cables are unattached. My battery was fully charged -- ready to go even after being put in bike and crated who knows? how many months earlier and sitting out in the dealers back lot in a snowdrift for 2 months (still in the crate).
 
Disconnecting the battery didn't really make much difference. I tried adjusting the CO level up to +12 and things started getting worse so it looks like you can go to far. I backed up to +10 and it is smoother though the surge is still present and I checked the TB sync a second time just to be sure, it was right on.

Here's a question for anyone out there with a PCIII or TI: With the bike stationary, in nuetral and warmed up, can you hold a steady 2,000 rpm? Mine will not, it hunts up and down between about 1700 and 2300.

I'm almost ready to take it to the dealer except I'm really reluctant to let ham fisted mechanics get hold of it, I always feel that the the one person who cares the most about my bike is me. I'm wondering though, is there an alternate map they can load or is that verboten?

 
The throttle response of the FJR can be very abrupt. It takes some getting used to or you can ham hand the thing and have some really jerking results. It's not the same as the no-load efi surge at about 2500 rpm when cruising in slow traffic. O2 and PC3 will help with the fuel mapping. The abruptness is a personal adjustment of the right wrist. Tickle the 145hp IL-4 motor and don't dab at it like an opposed 2 or 4 motor (beemer) or less powerful, chain driven IL3 (st).

btw: +5 to +7 seems to have historically been the max to change the O2. Without a gas tester (at the headers with RivNuts) I'd not go above +7.

 
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Thanks all. I think I'm going to go back to stock settings and then maybe work up at 2 point at a time. I initially went to +7 and then up from there so maybe there's a point between factory and +7 that will work. The surge is evident at very light throttle, ie just coasting or barely maintaining speed which from my understanding is usually related to being set a little lean. My idle is fine, very smooth in fact so I don't think I have a loose vacumn hose.

Is the TPS adjustable, I remember playing with it on the R1150RT and it did help a little. There were specific voltage values to measure so you could dial it up or down fairly accurately, does the FJR have this adjustablity?

 
Here is something from left field......What about removing one of the throtle return springs? I have read a few post about people removing on of the springs and they found the bike smoother to operate......

 
Vulcan,

I never even thought of that. It wouldn't change the CO settings but it would lighten the twist, I might just have to try that, thanks!

 
Thanks all.  I think I'm going to go back to stock settings and then maybe work up at 2 point at a time.  I initially went to +7 and then up from there so maybe there's a point between factory and +7 that will work.  The surge is evident at very light throttle, ie just coasting or barely maintaining speed which from my understanding is usually related to being set a little lean.  My idle is fine, very smooth in fact so I don't think I have a loose vacumn hose.
Is the TPS adjustable, I remember playing with it on the R1150RT and it did help a little.  There were specific voltage values to measure so you could dial it up or down fairly accurately, does the FJR have this adjustablity?
what you earlier described didn't sound like efi surge as much as it sounded like being still in the learning curve of how sensitive the throttle can be when it puts that much HP to the rear tire. Going back to OEM O2 settings and giving yourself some time to adjust to the bike might be worth a try.

 
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