2003 stumble when launching

[ANZAC]

Good to know about those filters - thanks RH

Sure would be nice to have non- ethanol gas back but I guess adding fuel treatment helps even the field.

 

[Mihalis fjr]

Good stuff guys. In will hook my DVM leads into the TPS connector today and go for a ride. The funny thing is, if I have the bike in neutral, just idling and rev the bike, the engine seems to slightly hesitate right around 2000 then revs very cleanly onward. What do your bikes do? Is the throttle response clean from idle upwards? Maybe that's just where the mapping switches over. I might just be over thinking my problem and this could just be normal for the FJR.

I had the same problem!From idle to about 2000+ rpm,then the bike runs great!Feels like to opens and closes quick the throttle slightly.It is a typical lean mixture problem made by Yamaha,to pass the CO emissions. Resolved at 90%+,when the Powercommander installed!Don't try to find anything other..

This is my opinion.

The problem comes from the stock Yamaha map in the ECU...

 

[Fred W]

Let me float an idea out there...

If what the OP is talking about is in fact the standard lean fueling issues of the FJR, maybe made worse over time due to deposits built up in the injectors, etc., a solution might be to do the Barbarian Jumper Mod and CO adjustments to add a bit of fuel in the idle and lower rpms.

The CO adjustment is primarily effective at idle and its effect tapers off as the throttle is opened, so it might be jkust what the doctor ordered here. And if it doesn't help, well at least it was free.

 

[Mihalis fjr]

Let me float an idea out there...
If what the OP is talking about is in fact the standard lean fueling issues of the FJR, maybe made worse over time due to deposits built up in the injectors, etc., a solution might be to do the Barbarian Jumper Mod and CO adjustments to add a bit of fuel in the idle and lower rpms.

The CO adjustment is primarily effective at idle and its effect tapers off as the throttle is opened, so it might be jkust what the doctor ordered here. And if it doesn't help, well at least it was free.

Fred,

I think that the CO adjustments are for the idle at about 1000-1200rpm..I really don't know if they can add a bit of fuel in the lower rpms from 1200-2000rpm.I tried to change these adjustments from - to + but i didn't noticed any difference!But immediately noticed a big difference when i installed the Powercommander..Problem solved at 90%+...!

 

[Fred W]

Mihalis, yes the primary effect is at idle, with a lessening effect as rpms and throttle openings increase, but there has been some enrichening reported above idle, especially by the guys that were opening up their airboxes a few years back.

May be worth a shot.

Another thing that might be worth trying is unplugging the O2 sensor. It may be the Fuel Injection's transition from closed loop operation to open loop mode that is causing the stumbles.

 

[ANZAC]

Thanks Mihalis and Fred

I checked for the Barbarian jumper mod when I took my air filter out and the wiring was stock with no mods. I did notice that the bike has an K/N air filter which looked pretty clean. Do you think the K/N filter might be goofing around with the ECU settings causing my issues? Are K/N filters used by many other FJR riders or do they prefer the OEM filters?

I could look at the O2 sensor, performing the jumper mod and playing with the settings as well as feeding her more fuel treatment. The bike is running better after the TBS adjustment but still has that lean spot below 2000 revs when moving off. If I keep the revs above 2000 all is well.

 

[Fred W]

Let's put it this way... The K&N is not helping here.

Especially if "clean" a K&N filter will (filter less dirt and) pass more air per unit of intake vacuum. When the Fuel Injection is operating in closed loop mode the ECU will compensate for the reduced intake resistance and adjust the fueling to hit the target fuel/air ratio. But when running open loop mode the K&N will result in a (slightly?) more lean F:A ratio. The fueling is already too lean from the factory especially at lower throttle openings and lower rpms. Making it leaner is not helping anything.

The entire premise of K&N filters increasing power was based on the carburetted engines from days past. In that case, opening up the intake and allowing more air coincidentally pulled more fuel from the carb jets, so the fuel mixture remained whatever it was and you ended up with more air/fuel mixture in the intake. It doesn't work that way with fuel injection as the injectors will squirt a predetermined amount of fuel when not in closed loop (which is most of the time).

I would not run a K&N filter in any of my machines as long as a stock paper filter is available. Google search on EMGO air filter for the FJR. They are much cheaper than Yamaha OE filters and identical to the stock filters right down to the mold markings in the plastic. If you are looking for even more economy, you can stretch the time between filter changes to about double the spec with no ill effect. A dirty filter actually filters dirt from the air better than a clean one, and the difference in fuel economy is negligible, if any.

 

[Denver_FJR]

...

Especially if "clean" a K&N filter will (filter less dirt and) pass more air per unit of intake vacuum. When the Fuel Injection is operating in closed loop mode the ECU will compensate for the reduced intake resistance and adjust the fueling to hit the target fuel/air ratio. But when running open loop mode the K&N will result in a (slightly?) more lean F:A ratio. The fueling is already too lean from the factory especially at lower throttle openings and lower rpms. Making it leaner is not helping anything. ...

I don't believe a K&N or other free-flowing air filter will cause a lean condition. The MAP sensor will detect the lower manifold pressure resulting from the free-er flowing filter which would simply result in a higher idle speed.

 

[ANZAC]

Well, it's probably worth a shot at getting a stock air filter for the bike. I will put in a EMGO or OEM filter as I have no idea when this K&N was installed.

I must say that getting off that side cover is a real pain due to all those little push pin and 1/4 turn phillips fasheners. Must get some more of those little guys as some are worn out and need replacing

 

[Fred W]

...

Especially if "clean" a K&N filter will (filter less dirt and) pass more air per unit of intake vacuum. When the Fuel Injection is operating in closed loop mode the ECU will compensate for the reduced intake resistance and adjust the fueling to hit the target fuel/air ratio. But when running open loop mode the K&N will result in a (slightly?) more lean F:A ratio. The fueling is already too lean from the factory especially at lower throttle openings and lower rpms. Making it leaner is not helping anything. ...

I don't believe a K&N or other free-flowing air filter will cause a lean condition. The MAP sensor will detect the lower manifold pressure resulting from the free-er flowing filter which would simply result in a higher idle speed.

You may be right.

We don't actually have a MAP sensor, per se, on the FJR. It is an Intake Air Pressure sensor. The (minor) difference is that an IAP sensor reports the relative (negative) difference of the manifold and outside atmosphere pressures and a MAP sensor measure the absolute pressure in the manifold.

The IAP signal along with throttle position and rpm signals are used to determine the basic injection quantity, but that sensor is measuring the manifold vacuum on the engine side of the throttle plates, which is primarily affected by the throttle plates.

There are also a bunch of other signals that are used to trim that basic value (Atmospheric pressure, Intake Air Temp, Coolant temp, acceleration/deceleration signals). I do not know that the IAP sensor would be capable of compensating for a restriction (or rather a lack of it) in the air filter box, but perhaps it does.

 

[Denver_FJR]

My theory is that because the FJR uses a speed/density type fuel injection, the IAP is a primary sensor used by the ECU to set mixture during open loop mode (and trimmed by other sensors/input as you mention). For example, other than IAP there is no input to the ECU when you adjust idle speed via the air bleed circuit. Additionally, you can manually activate the cold start circuit by depressing the plungers and see an immediate increase in engine RPM, as if you opened the throttle. Thus (more theory here

) a free-er-flowing filter, although before the throttle plates would be no difference than allowing more air via the idle or cold start circuits resulting in corresponding higher RPM.

 

[Fred W]

That all makes sense to me.

In which case the net gain of installing the K&N would be zero (just the equivalent of opening the throttle plate or air screws a little more).

 

[bunky]

Thanks Pilot! BTW I'm in CA (bay area) and never thought of a gas problem, does anyone know if it is possible to

buy real gas anymore in CA? Are there special additives to use for ethanol caused problems?

I'll try Google and a NAPA

 

[Fred W]

It depends how far you want to drive.

PureGas.org

 

[ANZAC]

I placed an order for two each of the EMGO air and oil filters through Amazon @ $30 bucks - sweet.

We will see if this helps out but I have the funny feeling after reading yet more and more threads about Power Commanders, that the best solution will come from installation of a PC111 and disconnect the O2 sensor located by the TPS.

 

[Fred W]

Try disconnecting the O2 sensor first. And try the Barbarian Jumper and upping the CO. It very well may save you $300.

 

[Mihalis fjr]

Try disconnecting the O2 sensor first. And try the Barbarian Jumper and upping the CO. It very well may save you $300.

Or to find a good used PCIII like mine,for about $100-150

 

[ionbeam]

ANZAC, just out of curiosity, what kind of bike were you riding before you got your FJR?

If I'm careful I can pull away from a dead stop with just the clutch, no gas. But, when I normally pull away I use 'sufficient' throttle, what ever that may be for the situation. I'm not sure what would happen with my FJR if I were to run the tach up to ~2k rpm and just released the clutch. Right now there is way too much snow for me to go check. Is there a possibility that your bucking and rough running could simply be related to rpms too low? Hey, it's worth asking, some cruiser guys have problems transitioning to a bike that needs to have wildly high rpms like 3k rpm to pull off smoothly.

Good luck with the hunt!

 

[Mihalis fjr]

I placed an order for two each of the EMGO air and oil filters through Amazon @ $30 bucks - sweet. We will see if this helps out but I have the funny feeling after reading yet more and more threads about Power Commanders, that the best solution will come from installation of a PC111 and disconnect the O2 sensor located by the TPS.

''but I have the funny feeling after reading yet more and more threads about Power Commanders, that the best solution will come from installation of a PC111 and disconnect the O2 sensor located by the TPS.''

Thought so..

 

[ANZAC]

Regarding Ionbeams question:

Last bike was a 2009 Triumph Street Triple which had a very clean but quick throttle. I had to balance the throttle with my middle and first finger resting on the brake level. The installation of the 1050 throttle tube helped but still easy does it.

My other bike is a 1986 Honda Nighthawk 700s with smooth buttery throttle thanks to the blessing of carbs

The FJR has a beautiful engine above 2000 revs and it seems to be very rider dependent on what or how you view throttle response. Mine is too lean and after learning more and more thanks to everyone's help I can say that it's normal to have issues below 2000 revs. Power Commander or jumper mods can sort this out. I will be using her as a commuter so I need the best low speed throttle response to safely ride in everyday traffic.