Over-fueling Fixes

[DenverSnowBike]

2010 KX450F EFI running a thermobob and engine guards, when I was in fender deep powder this wknd, I still couldn't keep engine temps up, so I was over-fueling and a little boggy.

Looking at Dobeck products, can I get away with the EJK Fuel Controller - GEN 3.5 (similar to FMF programmer), or do I need to get the AFR+Autotune - GEN 4?

Thanks in advance!

 

[SuperchargedWS6]

Thermobob, engine shrouds, and blocking one rad with cardboard works for my Suzuki. Temps perfect. Are you blocking g your rads at all? That could be the problem.

I have the gen 4 dobeck and it has worked well for keeping Afr correct.

 

[DenverSnowBike]

Thermobob, engine shrouds, and blocking one rad with cardboard works for my Suzuki. Temps perfect. Are you blocking g your rads at all? That could be the problem.

I have the gen 4 dobeck and it has worked well for keeping Afr correct.

With the snow so deep they were getting blocked...

 

[DieselTwitch]

In my opinion blocking your radiator if your engine isn't even getting up to temperature is kind of pointless when you have a thermal Bob. You need to work on getting the core of the engine hotter to begin with the engine shrouds are probably the best way. One shortcut I just learned is in deep snow to disconnect your engine temp sensor. This will force the ECU into its default fueling mode and run only on the mass airflow sensor and temp sensor if you have a mass airflow sensor.

 

[DenverSnowBike]

In my opinion blocking your radiator if your engine isn't even getting up to temperature is kind of pointless when you have a thermal Bob. You need to work on getting the core of the engine hotter to begin with the engine shrouds are probably the best way. One shortcut I just learned is in deep snow to disconnect your engine temp sensor. This will force the ECU into its default fueling mode and run only on the mass airflow sensor and temp sensor if you have a mass airflow sensor.

makes sense to do that...thanks man

 

[Wheel House Motorsports]

This will force the ECU into its default fueling mode and run only on the mass airflow sensor and temp sensor if you have a mass airflow sensor.

It is actually a MAP sensor(Manifold Air Pressure). None of the bikes run a MAF (Mass Air Flow).

I would be curious to throw an AFR gauge on them when doing this. Although yes it is a cheat and might work, if it defaults to fueling for say 60* it may be on the leaner side of things. While it may work for one bike, it may not work for another.

A full closed loop fuel tuner like a dobeck gen 4 in conjunction with a thermostat (like a thermobob) and some shrouding is your ideal setup. Dobeck's EJK is an option that could be used to help the issue but the Gen4 AFR plus is most ideally suited for the massive fuel change needs the snow causes.

 

[DieselTwitch]

It is actually a MAP sensor(Manifold Air Pressure). None of the bikes run a MAF (Mass Air Flow).

I would be curious to throw an AFR gauge on them when doing this. Although yes it is a cheat and might work, if it defaults to fueling for say 60* it may be on the leaner side of things. While it may work for one bike, it may not work for another.

A full closed loop fuel tuner like a dobeck gen 4 in conjunction with a thermostat (like a thermobob) and some shrouding is your ideal setup. Dobeck's EJK is an option that could be used to help the issue but the Gen4 AFR plus is most ideally suited for the massive fuel change needs the snow causes.

Wrong wording but same idea. And yeah it will deffenently run lean. But even the map sensors should provide enough info to the ECU to get it close and adjust for the cooler air temps with out dumping huge amounts of fuel in.

After seeing my buddy with a gen 4 afr+ have major problems I'm hesitant on running one. That and there's a thread here that is full of people having problem with their gen4's. I feel that you need to get back to basics on getting the engine to run right first then add on fuel controllers, otherwise you just mask problems in a pile of mods.

 

[retired motoman]

Engine temps my 2 cents

Once we got the engine temperature to normal operating range the over fueling issue was gone.

Full engine shrouds lined with yoga mat material (to increase crankcase and oil temp), removable radiator block off shrouds, rear engine shroud (keep track blast off rear of engine), thermostat and coolant temp gauge (so you know). I also have insulated the stock engine temp sensor for a more accurate reading.

We use no additional fuel management boxes or controller.

 

[Rush44]

The air temp sensor in your intake boot is the source of your actual overfueling. The KX is famous for REALLY overfueling because of it (I had a 2011) and the bike runs a little rich already out of the gate. People are correct that you need a tstat and some kind of engine shielding (I just shield my sump and it works real good) to help the bike warm up.

Even if you had the bike at a constant 180F you will technically still overfuel because the air temp sensor will call for the ECU to richen even if the coolant temperature is fine. This is where the aftermarket fuel controller will correct the call for extra fuel and set it to the correct AFR. Yes there have been some Dobeck troubles posted on the forums, but they are not problems with the actual controller or the Gen4 system. Getting the bike warm without a controller will keep fuel out of the oil since the rings will seat properly and you won't get blowby into the case... but you'll still overfuel and send it out the tailpipe instead.

 

[DenverSnowBike]

The air temp sensor in your intake boot is the source of your actual overfueling. The KX is famous for REALLY overfueling because of it (I had a 2011) and the bike runs a little rich already out of the gate. People are correct that you need a tstat and some kind of engine shielding (I just shield my sump and it works real good) to help the bike warm up.

Even if you had the bike at a constant 180F you will technically still overfuel because the air temp sensor will call for the ECU to richen even if the coolant temperature is fine. This is where the aftermarket fuel controller will correct the call for extra fuel and set it to the correct AFR. Yes there have been some Dobeck troubles posted on the forums, but they are not problems with the actual controller or the Gen4 system. Getting the bike warm without a controller will keep fuel out of the oil since the rings will seat properly and you won't get blowby into the case... but you'll still overfuel and send it out the tailpipe instead.

So if you wanted to try an cheat, would you unplug the intake boot sensor or the engine temp sensor?

I ordered a JD Jettings controller, I have a few after market products on my bike, so that'll help clean it up, plus I can lean it out a little.

Made some rad blockers, and wrapped my engine better, we will see how she rips tomorrow.

 

[Rush44]

So if you wanted to try an cheat, would you unplug the intake boot sensor or the engine temp sensor?

I tried this on my KX and it didn't help as far as I could notice. For all I know the lack of the sensor may trip the ECU into an overfueling "limp" mode... not sure. I've asked lot of Kawi guys about the sensor and nobody has an answer. The controller and warming the bike up helped eliminate the problem... the controller allowed me to fine tune the AFR, pull more power out of the bike, and increase fuel economy.