air/fuel mixture adjustment?

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FJRME

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With a stock bike( no power commander or special map) is there a fuel mixture adjustment that can be done to richen the mix? I have a friend with an 04, and his wife has an 05. He says he thought the stock setting was a little lean, helping to contribute to the heat issue, and that the mix can be richened up resulting in a cooler running bike. He thinks he saw a thread somewhere, but does not recall where. He thought it involved the dash display, and changing parameters. I tried the search, and came up dry, and I found nothing in the shop manual to indicate an adjustment procedure for mixture control. My Carbtune should be in the mail now, and a TBS is due on all three bikes(his two plus mine). He mentioned this mixture change, but I'm stumped.

Any thoughts guys? Thanks in advance for the help.

 
Funny thing. I searched several times with no luck. After I posted, I immediately found the Barbaian Jumper mod, and the corresponding co change. I believe thats what my friend must have seen. I should have searched for co setting change perhaps.

To revise my question a little: Is the Barbarian mod necessary for 05? Only 03, and 04 are shown on the page, and both are different mods. With the info on the CO adjust page, can't I just bump my settings up 5-7 points and be in the game, or do I really need to buy an analyzer and measure CO first?

Thanks in advance- again.

 
If your goal is to control engine heat, I'd search under heat fixes and leave the mixture alone. Small mixture changes will only have a modest effect on heat output, and larger changes in mixture will make fuel economy and range plummet, not to mention the bike will run like shit. There's a variety of heat fixes out there that will do much more to increase your comfort.

 
Yeah, I agree. Like I say, I'm searching for a friend. I did some of the heat mods, mostly to cool the tank down. I've never really had a problem with the heat. The CO setting mod and BJ mod claim in the article to cool it down, AND make it run better, but again, I've had no issue with mine. I am doing the TBS for all three bikes, and my friend asked about changing the mix at the same time. I think I might just print off the articles for him and let him mess with it if he wants, that way I'm not responsible for it. The TBS is no biggie, but I agree about the mix adjust. Did the mods help the earlier bikes a lot. If not, The BJ seems a little scary. Expensive smoke.

 
FJRME is talking about making the bike run cooler not " heat fixes " to make the rider more comfortable.

Yes you can adjust the CO setting per the dash. The 04 / 05 fix is the same procedure from what's been posted up before. Your right in bumping the #'s 4 or 5 points, that where most folk seem to find the most benefit.

The results posted previously is the bike runs cooler , taking longer to hit four bars on the temp gauge. It's also easy to reverse the procedure if you do not like the results.

 
Is it necessary to do the Jumper mod on an 05, or can I just go straight to the CO setting?

 
Mine's an '05. I did the TBS both at idle and the TBS Yamaha recommends that you DON"T do, up at 4000 rpm. My goal was to smooth out vibration, and it worked. I was surprised how far out of synch mine was, both at idle and higher rpm. It took some work to get it right, but it was worth it.

Getting back to the heat issue, does yours have the reflective material stuck to the bottom of the tank? Mine came with it from the factory and the tank doesn't get hot. Others have reported '05s NOT coming with this component, and (no surprise) their tank gets very hot. The reflective material is like aluminum foil with adhesive on one side, cut and formed to fit the bottom of the tank. Worth looking for during your TBS.

 
FJRME is talking about making the bike run cooler not " heat fixes " to make the rider more comfortable.
After re-reading his original posts, I agree that his topic was probably realted more to engine temperature. My mistake.

I still think the BJ mod or any mixture mod would have only a minor effect on engine temperature, which is ultimately controlled by the thermostat and the radiator/cooling fan. You might save a few seconds before the stat opens by making the mod, or save a few seconds before the fan comes on at 4 bars. But if you're sitting still, the bike will hit 4 bars no matter what, and the fan will come on. I think a far more effective solution would be finding a way to run a slightly cooler thermostat, and then lower the temp at which the fan comes on. The fan would still blow heat back at the rider, but not the superheated air you sometimes get at 4 bars and above. Accourse if you go out and ride hard and then pull up and sit at a long red light, nothing will save you short of running a red light....
 
Yes, it does, but I added another layer. Tank does not get hot. A bit of foam where the seat meets the tank took care of the comfort issue also.

I am going to do both TBS's on mine. Glad it worked for you. I have vibration at 4k also. It makes my right hand numb. Not left, only right. I'm right handed, and write and use computer at work. I've added heavy bar ends(look cool), Vista cruise(great farkle for the 24 bucks), 6 degree risers( sit me right where I want to be), return spring unwind(when I insulated the tank), and still numb. Hope the TBS's help. Can't hurt.

Highlander is correct. The goal that my friend is interested in is a cooler running bike, not rider comfort. He has done the heat fixes also. I just don't know about the necessity of doing the jumper mod on an 05. I guess I should just go down to the garage and turn the key to see if I can got to the right screen.

 
I think the key to running cooler is to ride nice twisty deserted two lane roads that have no stop signs.

I agree about the cooling fans and stat change etc. What is the purpose of the

BJ and CO change that makes it desirable to do? The articles don't rave about killer

hp improvements, they say runs better, and cooler, but not by how much. I thought that if it's in FJRTECH, it must be something worthwhile though. And i'm strill curious which version of the BJ to do to an 05. They're different between 03, and 04.

 
I went to the bike and got into dianostic mode. There is no prompt for CO. BJ is needed I guess. I think I'll let my buddy let the smoke out of his bikes himself. I'll do the syncs and let him do the mods.

Thanks guys!

 
As the fellow who first hooked an oscilloscope up to the FJR ECU and worked out the mysteries of the Barbarian Jumper, I'd like to say that there is virtually no risk of letting the smoke out if you follow the directions. I was playing with my own baby and took very careful measurements before I first grounded the ECU terminal. Thousands of bikes have been so modded in the last 3 years and I've not heard of a single damaged ECU. There is a far greater risk of damaging the wiring to the ECU by tugging away on the wires without having fully released the locking tab. This happened once early on. That is why the directions stress to push the connectors out, not pull on the wires to remove them.

As for the difference in the 03 vs 04: There really isn't a difference. Yamaha found out that we figured out how to access the adjustment so they stopped supplying us with the jumper, but the configuration remained the same. The use of the resistor was originally a precaution because I didn't have an 04 available to connect up to a scope. Subsequent testing reveals no quantatative differences in the ECUs. But the resistor works, so why mess with success?

As far as effects go, I think I'm pretty clearly on the record as stating that one should make proper measurements so that the adjustments are customized for each bike as required. There's no universal "magic number" that will help all bikes, or even all cylinders. People that have had the work done with CO measurements on a dyno report different results and different required adjustments for each cylinder.

Increasing the CO count increases the BASE injector duration. That is the single greatest factor determining total injector duration AT IDLE. As you open the throttle, the base duration does not change, but other factors (calculated mass air flow, etc.) increase the total duration so the base duration becomes a smaller and smaller percentage of the total. At high RPM and wide open throttle, the base duration is an almost negligible percentage of the total.

So: No, the Barbarian Jumper mod and adjusting the CO will NOT increase your peak HP. Ever. It MAY help in the low- to mid- range (this has been confirmed on a dyno). It MAY help low speed surge drivability issues. It MAY help reduce generated engine heat at idle. Those effects are ONLY possible if the adjustment was required in the first place.

It won't affect generated engine heat at cruise. It won't affect highway mileage. Once the bike gets rolling at moderate throttle openings, the system switches to closed loop mode and the O2 sensor controls the mixture.

I hope this clears up any misconceptions. Have fun, play safe but don't expect miracles.

 
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Great post torch. If you really want to do anything very significant with mixture customization, I'd just get the PC.

And as others have said, richening the mixture will do very little (if anything at all) for the engine heat issues. Mixture may have a significant effect on localized engine temps (e.g., the exhaust valve face), but not on the overall heat of the engine. And unless you go really rich, a small leaning of the mixture may actually raise temperatures - for emissions control, our engines operate on the lean side of peak EGT and small amounts of richening RAISE the EGT, not lower it.

IMHO, running richer mixtures to control overall heat rejection to the rider is a silly idea.

- Mark

 
Great post torch.  If you really want to do anything very significant with mixture customization, I'd just get the PC.
I agree, great post torch, and thanks for the explanation. One other question about TBS, I notice that some think a TBS is more effective if you do it at 4000 rpms instead of idle speeds, but it would seem that the throttle position required to make 4000 rpms would be far less in a no-load situation than when actually riding at 70 mph making the TBS at a 4000 rpms somewhat meaningless. True or false?

 
I notice that some think a TBS is more effective if you do it at 4000 rpms instead of idle speeds, but it would seem that the throttle position required to make 4000 rpms would be far less in a no-load situation than when actually riding at 70 mph making the TBS at a 4000 rpms somewhat meaningless.  True or false?
True and false. It is true that the throttle position under no-load is considerably less than the throttle position under load. It is false to assume that it has no bearing.

For those that are unfamiliar with the linkage between the throttle bodies, the throttle cable is attached to the #3 throttle shaft. The #4 throttle shaft is connected to the #3 throttle shaft by way of two little springs. Similarly, #1 is connected to #2 and #2 is connected to #3. So when you twist the throttle, the cable does not open the butterfly on #1 directly. It opens #3, which applies pressure on the springs of #2 and eventually opens it, which applies pressure on the springs of #1 and eventually opens it.

Opening the throttle, even without load, takes the butterflies off the stops and puts tension on the springs, settling everything into the position they will assume at 4,000 rpm under load. So while the actual throttle opening used during the synch is not the same, the effect is.

Why wasn't this done at the factory? I'm sure it was. The problem is that springs fatigue over time and each spring fatigues at a slightly different rate. These things are extremely sensitive -- I love showing people how just the mere weight of the screwdriver resting on the adjustment screw makes a difference in the vacuum readings. So, while it was undoubtedly perfect in the factory, things slip out of adjustment over time.

BTW: I personally do it around 3,000 rpm. Others have since suggested 4,000, reasoning that 4,000 is a more common resonance point. I don't think the actual rpm makes the slightest difference -- what is important is that the butterflies are all off the stops and the springs are at operating tension.

I will close with the same warning list I gave when I originally suggested it: This is NOT the Yamaha recommended procedure. Yamaha does not authorize fiddling with those screws. Yamaha puts a dot of paint on each screw so they can tell if you fiddled with it. Do this at your own risk. Just because it worked for me does not mean it will work for you. If you bugger up your bike, I wasn't there, I didn't do it, He only looked like me and I don't know her.

Etc.

 
One other thing:

Often at this point in these discussions the former Concours owners start asking about balance shaft adjustments. I played with them and found that they cannot be "tuned" the same way the Connie shafts could. The FJR balance shaft adjustments are strictly a gear-lash adjustment with a very narrow window between too tight and too loose. They cannot be used to tune out the vibration.

 
I agree with what torch has written. I did the Barbarian on my 05 shortly after purchase, and it did help somewhat with surging and throttle response. It did not, however, mitigate the heat issue that I could tell. I have also synched the TB's at 4000 rpm, and the results were excellent. Not the easiest thing to do, but well worth the effort. Combined with the PC, it has made 'ol Frank into a completely different machine than the one that left the dealer in July 04.

 
Thanks Torch, and all. I think I'll forget the mixture change and just do the TBS. MY bike has no issues. My friend was thinking about a mix change, so I told him I would research it for him. I will print this thread and he can make up his own mind. I have no surge, throttle response is great, etc. I received my Carbtune in the mail today, so I will do the sync on mine tonight.

Hey radman- is the Barbarian jumper the same procedure for 05 as previous years?

You're the first with an 05 to respond. My mention of smoking the ecu was in reference to moving the wrong lead if 05 is different, but no one has touched on that yet. Thanks to all.

 
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